Change relevant Assert calls to throw IllegalStateException

Change certain Assert class from `assert...` to `assertState`
so that a more appropriate `IllegalStateException` is thrown.

Fixes gh-43779

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/availability/AvailabilityStateHealthIndicator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -69,7 +69,7 @@ public class AvailabilityStateHealthIndicator extends AbstractHealthIndicator {
 		if (!this.statusMappings.containsKey(null) && Enum.class.isAssignableFrom(stateType)) {
 			EnumSet elements = EnumSet.allOf((Class) stateType);
 			for (Object element : elements) {
-				Assert.isTrue(this.statusMappings.containsKey(element),
+				Assert.state(this.statusMappings.containsKey(element),
 						() -> "StatusMappings does not include " + element);
 			}
 		}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/management/HeapDumpWebEndpoint.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -209,7 +209,7 @@ public class HeapDumpWebEndpoint {
 
 		@Override
 		public File dumpHeap(Boolean live) throws IOException, InterruptedException {
-			Assert.isNull(live, "OpenJ9DiagnosticsMXBean does not support live parameter when dumping the heap");
+			Assert.state(live == null, "OpenJ9DiagnosticsMXBean does not support live parameter when dumping the heap");
 			return new File(
 					(String) ReflectionUtils.invokeMethod(this.dumpHeapMethod, this.diagnosticMXBean, "heap", null));
 		}

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/availability/AvailabilityStateHealthIndicatorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,6 +28,7 @@ import org.springframework.boot.availability.LivenessState;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 
 /**
@@ -67,7 +68,7 @@ class AvailabilityStateHealthIndicatorTests {
 
 	@Test
 	void createWhenStatusMappingDoesNotCoverAllEnumsThrowsException() {
-		assertThatIllegalArgumentException()
+		assertThatIllegalStateException()
 			.isThrownBy(() -> new AvailabilityStateHealthIndicator(this.applicationAvailability, LivenessState.class,
 					(statusMappings) -> statusMappings.add(LivenessState.CORRECT, Status.UP)))
 			.withMessage("StatusMappings does not include BROKEN");

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationImportSelector.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -57,6 +57,7 @@ import org.springframework.core.type.classreading.CachingMetadataReaderFactory;
 import org.springframework.core.type.classreading.MetadataReaderFactory;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
+import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
 
 /**
@@ -170,7 +171,7 @@ public class AutoConfigurationImportSelector implements DeferredImportSelector,
 	protected AnnotationAttributes getAttributes(AnnotationMetadata metadata) {
 		String name = getAnnotationClass().getName();
 		AnnotationAttributes attributes = AnnotationAttributes.fromMap(metadata.getAnnotationAttributes(name, true));
-		Assert.notNull(attributes, () -> "No auto-configuration attributes found. Is " + metadata.getClassName()
+		Assert.state(attributes != null, () -> "No auto-configuration attributes found. Is " + metadata.getClassName()
 				+ " annotated with " + ClassUtils.getShortName(name) + "?");
 		return attributes;
 	}
@@ -195,7 +196,7 @@ public class AutoConfigurationImportSelector implements DeferredImportSelector,
 		ImportCandidates importCandidates = ImportCandidates.load(this.autoConfigurationAnnotation,
 				getBeanClassLoader());
 		List<String> configurations = importCandidates.getCandidates();
-		Assert.notEmpty(configurations,
+		Assert.state(!CollectionUtils.isEmpty(configurations),
 				"No auto configuration classes found in " + "META-INF/spring/"
 						+ this.autoConfigurationAnnotation.getName() + ".imports. If you "
 						+ "are using a custom packaging, make sure that file is correct.");

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/batch/JobLauncherApplicationRunner.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -112,10 +112,10 @@ public class JobLauncherApplicationRunner
 
 	@Override
 	public void afterPropertiesSet() {
-		Assert.isTrue(this.jobs.size() <= 1 || StringUtils.hasText(this.jobName),
+		Assert.state(this.jobs.size() <= 1 || StringUtils.hasText(this.jobName),
 				"Job name must be specified in case of multiple jobs");
 		if (StringUtils.hasText(this.jobName)) {
-			Assert.isTrue(isLocalJob(this.jobName) || isRegisteredJob(this.jobName),
+			Assert.state(isLocalJob(this.jobName) || isRegisteredJob(this.jobName),
 					() -> "No job found with name '" + this.jobName + "'");
 		}
 	}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cache/CacheAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -102,7 +102,7 @@ public class CacheAutoConfiguration {
 
 		@Override
 		public void afterPropertiesSet() {
-			Assert.notNull(this.cacheManager.getIfAvailable(),
+			Assert.state(this.cacheManager.getIfAvailable() != null,
 					() -> "No cache manager could be auto-configured, check your configuration (caching type is '"
 							+ this.cacheProperties.getType() + "')");
 		}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -250,8 +250,8 @@ class OnBeanCondition extends FilteringSpringBootCondition implements Configurat
 		ConfigurableListableBeanFactory beanFactory = spec.getContext().getBeanFactory();
 		if (spec.getStrategy() == SearchStrategy.ANCESTORS) {
 			BeanFactory parent = beanFactory.getParentBeanFactory();
-			Assert.isInstanceOf(ConfigurableListableBeanFactory.class, parent,
+			Assert.state(parent instanceof ConfigurableListableBeanFactory,
-					"Unable to use SearchStrategy.ANCESTORS");
+					"Unable to use SearchStrategy.ANCESTORS without ConfigurableListableBeanFactory");
 			beanFactory = (ConfigurableListableBeanFactory) parent;
 		}
 		return beanFactory;

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnResourceCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -45,7 +45,7 @@ class OnResourceCondition extends SpringBootCondition {
 		ResourceLoader loader = context.getResourceLoader();
 		List<String> locations = new ArrayList<>();
 		collectValues(locations, attributes.get("resources"));
-		Assert.isTrue(!locations.isEmpty(),
+		Assert.state(!locations.isEmpty(),
 				"@ConditionalOnResource annotations must specify at least one resource location");
 		List<String> missing = new ArrayList<>();
 		for (String location : locations) {

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration.java

@@ -583,7 +583,7 @@ public class FlywayAutoConfiguration {
 		Extension(FluentConfiguration configuration, Class<E> type, String name) {
 			this.extension = SingletonSupplier.of(() -> {
 				E extension = configuration.getPluginRegister().getPlugin(type);
-				Assert.notNull(extension, () -> "Flyway %s extension missing".formatted(name));
+				Assert.state(extension != null, () -> "Flyway %s extension missing".formatted(name));
 				return extension;
 			});
 		}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/hazelcast/HazelcastProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -52,7 +52,7 @@ public class HazelcastProperties {
 		if (this.config == null) {
 			return null;
 		}
-		Assert.isTrue(this.config.exists(),
+		Assert.state(this.config.exists(),
 				() -> "Hazelcast configuration does not exist '" + this.config.getDescription() + "'");
 		return this.config;
 	}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration.java

@@ -292,7 +292,7 @@ public class JacksonAutoConfiguration {
 				// Find the field (this way we automatically support new constants
 				// that may be added by Jackson in the future)
 				Field field = findPropertyNamingStrategyField(fieldName);
-				Assert.notNull(field, () -> "Constant named '" + fieldName + "' not found");
+				Assert.state(field != null, () -> "Constant named '" + fieldName + "' not found");
 				try {
 					builder.propertyNamingStrategy((PropertyNamingStrategy) field.get(null));
 				}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/XADataSourceAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -96,7 +96,8 @@ public class XADataSourceAutoConfiguration implements BeanClassLoaderAware {
 		try {
 			Class<?> dataSourceClass = ClassUtils.forName(className, this.classLoader);
 			Object instance = BeanUtils.instantiateClass(dataSourceClass);
-			Assert.isInstanceOf(XADataSource.class, instance);
+			Assert.state(instance instanceof XADataSource,
+					() -> "DataSource class " + className + " is not an XADataSource");
 			return (XADataSource) instance;
 		}
 		catch (Exception ex) {

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/saml2/Saml2RelyingPartyRegistrationConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -175,8 +175,8 @@ class Saml2RelyingPartyRegistrationConfiguration {
 		try (InputStream inputStream = location.getInputStream()) {
 			PemContent pemContent = PemContent.load(inputStream);
 			PrivateKey privateKey = pemContent.getPrivateKey();
-			Assert.isInstanceOf(RSAPrivateKey.class, privateKey,
+			Assert.state(privateKey instanceof RSAPrivateKey,
-					"PrivateKey in resource '" + location + "' must be an RSAPrivateKey");
+					() -> "PrivateKey in resource '" + location + "' must be an RSAPrivateKey");
 			return (RSAPrivateKey) privateKey;
 		}
 		catch (Exception ex) {

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/ssl/CertificateMatcher.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -53,7 +53,7 @@ class CertificateMatcher {
 		Assert.notNull(privateKey, "Private key must not be null");
 		this.privateKey = privateKey;
 		this.signature = createSignature(privateKey);
-		Assert.notNull(this.signature, "Failed to create signature");
+		Assert.state(this.signature != null, "Failed to create signature");
 		this.generatedSignature = sign(this.signature, privateKey);
 	}
 

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/ssl/PropertiesSslBundle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -127,7 +127,7 @@ public final class PropertiesSslBundle implements SslBundle {
 		if (properties.isVerifyKeys()) {
 			CertificateMatcher certificateMatcher = new CertificateMatcher(pemSslStore.privateKey());
 			Assert.state(certificateMatcher.matchesAny(pemSslStore.certificates()),
-					"Private key in %s matches none of the certificates in the chain".formatted(propertyName));
+					() -> "Private key in %s matches none of the certificates in the chain".formatted(propertyName));
 		}
 		return pemSslStore;
 	}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/batch/BatchAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -91,7 +91,7 @@ import org.springframework.transaction.PlatformTransactionManager;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -484,7 +484,7 @@ class BatchAutoConfigurationTests {
 		JobLauncherApplicationRunner runner = createInstance();
 		runner.setJobs(Arrays.asList(mockJob("one"), mockJob("two")));
 		runner.setJobName("three");
-		assertThatIllegalArgumentException().isThrownBy(runner::afterPropertiesSet)
+		assertThatIllegalStateException().isThrownBy(runner::afterPropertiesSet)
 			.withMessage("No job found with name 'three'");
 	}
 
@@ -492,7 +492,7 @@ class BatchAutoConfigurationTests {
 	void whenTheUserDefinesAJobNameThatDoesNotExistWithRegisteredJobFailsFast() {
 		JobLauncherApplicationRunner runner = createInstance("one", "two");
 		runner.setJobName("three");
-		assertThatIllegalArgumentException().isThrownBy(runner::afterPropertiesSet)
+		assertThatIllegalStateException().isThrownBy(runner::afterPropertiesSet)
 			.withMessage("No job found with name 'three'");
 	}
 

spring-boot-project/spring-boot-devtools/src/main/java/org/springframework/boot/devtools/restart/Restarter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -272,7 +272,7 @@ public class Restarter {
 	}
 
 	private Throwable doStart() throws Exception {
-		Assert.notNull(this.mainClassName, "Unable to find the main class to restart");
+		Assert.state(this.mainClassName != null, "Unable to find the main class to restart");
 		URL[] urls = this.urls.toArray(new URL[0]);
 		ClassLoaderFiles updatedFiles = new ClassLoaderFiles(this.classLoaderFiles);
 		ClassLoader classLoader = new RestartClassLoader(this.applicationClassLoader, urls, updatedFiles);

spring-boot-project/spring-boot-docker-compose/src/main/java/org/springframework/boot/docker/compose/core/DefaultConnectionPorts.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -97,7 +97,8 @@ class DefaultConnectionPorts implements ConnectionPorts {
 	@Override
 	public int get(int containerPort) {
 		Integer hostPort = this.portMappings.get(containerPort);
-		Assert.state(hostPort != null, "No host port mapping found for container port %s".formatted(containerPort));
+		Assert.state(hostPort != null,
+				() -> "No host port mapping found for container port %s".formatted(containerPort));
 		return hostPort;
 	}
 

spring-boot-project/spring-boot-docker-compose/src/main/java/org/springframework/boot/docker/compose/core/DefaultDockerCompose.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -102,7 +102,7 @@ class DefaultDockerCompose implements DockerCompose {
 		Map<String, DockerCliInspectResponse> inspected = inspect(runningPsResponses);
 		for (DockerCliComposePsResponse psResponse : runningPsResponses) {
 			DockerCliInspectResponse inspectResponse = inspectContainer(psResponse.id(), inspected);
-			Assert.notNull(inspectResponse, () -> "Failed to inspect container '%s'".formatted(psResponse.id()));
+			Assert.state(inspectResponse != null, () -> "Failed to inspect container '%s'".formatted(psResponse.id()));
 			result.add(new DefaultRunningService(this.hostname, dockerComposeFile, psResponse, inspectResponse));
 		}
 		return Collections.unmodifiableList(result);

spring-boot-project/spring-boot-docker-compose/src/main/java/org/springframework/boot/docker/compose/core/DockerComposeFile.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -47,7 +47,7 @@ public final class DockerComposeFile {
 	private final List<File> files;
 
 	private DockerComposeFile(List<File> files) {
-		Assert.state(!files.isEmpty(), "Files must not be empty");
+		Assert.isTrue(!files.isEmpty(), "'files' must not be empty");
 		this.files = files.stream().map(DockerComposeFile::toCanonicalFile).toList();
 	}
 
@@ -112,7 +112,7 @@ public final class DockerComposeFile {
 		if (!base.exists()) {
 			return null;
 		}
-		Assert.isTrue(base.isDirectory(), () -> "'%s' is not a directory".formatted(base));
+		Assert.state(base.isDirectory(), () -> "'%s' is not a directory".formatted(base));
 		Path basePath = base.toPath();
 		for (String candidate : SEARCH_ORDER) {
 			Path resolved = basePath.resolve(candidate);

spring-boot-project/spring-boot-docker-compose/src/test/java/org/springframework/boot/docker/compose/core/DockerComposeFileTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,6 +27,7 @@ import org.springframework.util.FileCopyUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link DockerComposeFile}.
@@ -104,7 +105,7 @@ class DockerComposeFileTests {
 	@Test
 	void findWhenWorkingDirectoryIsNotDirectoryThrowsException() throws Exception {
 		File file = createTempFile("iamafile");
-		assertThatIllegalArgumentException().isThrownBy(() -> DockerComposeFile.find(file))
+		assertThatIllegalStateException().isThrownBy(() -> DockerComposeFile.find(file))
 			.withMessageEndingWith("is not a directory");
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/BuilderBuildpack.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -65,7 +65,7 @@ class BuilderBuildpack implements Buildpack {
 			.of(unambiguous ? reference.getSubReference(PREFIX) : reference.toString());
 		BuildpackMetadata buildpackMetadata = findBuildpackMetadata(context, builderReference);
 		if (unambiguous) {
-			Assert.isTrue(buildpackMetadata != null, () -> "Buildpack '" + reference + "' not found in builder");
+			Assert.state(buildpackMetadata != null, () -> "Buildpack '" + reference + "' not found in builder");
 		}
 		return (buildpackMetadata != null) ? new BuilderBuildpack(buildpackMetadata) : null;
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/BuilderMetadata.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -158,7 +158,7 @@ class BuilderMetadata extends MappedObject {
 	static BuilderMetadata fromImageConfig(ImageConfig imageConfig) throws IOException {
 		Assert.notNull(imageConfig, "ImageConfig must not be null");
 		String json = imageConfig.getLabels().get(LABEL_NAME);
-		Assert.notNull(json, () -> "No '" + LABEL_NAME + "' label found in image config labels '"
+		Assert.state(json != null, () -> "No '" + LABEL_NAME + "' label found in image config labels '"
 				+ StringUtils.collectionToCommaDelimitedString(imageConfig.getLabels().keySet()) + "'");
 		return fromJson(json);
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/BuildpackLayersMetadata.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -77,7 +77,7 @@ final class BuildpackLayersMetadata extends MappedObject {
 	static BuildpackLayersMetadata fromImageConfig(ImageConfig imageConfig) throws IOException {
 		Assert.notNull(imageConfig, "ImageConfig must not be null");
 		String json = imageConfig.getLabels().get(LABEL_NAME);
-		Assert.notNull(json, () -> "No '" + LABEL_NAME + "' label found in image config labels '"
+		Assert.state(json != null, () -> "No '" + LABEL_NAME + "' label found in image config labels '"
 				+ StringUtils.collectionToCommaDelimitedString(imageConfig.getLabels().keySet()) + "'");
 		return fromJson(json);
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/BuildpackMetadata.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -94,7 +94,7 @@ final class BuildpackMetadata extends MappedObject {
 	static BuildpackMetadata fromImageConfig(ImageConfig imageConfig) throws IOException {
 		Assert.notNull(imageConfig, "ImageConfig must not be null");
 		String json = imageConfig.getLabels().get(LABEL_NAME);
-		Assert.notNull(json, () -> "No '" + LABEL_NAME + "' label found in image config labels '"
+		Assert.state(json != null, () -> "No '" + LABEL_NAME + "' label found in image config labels '"
 				+ StringUtils.collectionToCommaDelimitedString(imageConfig.getLabels().keySet()) + "'");
 		return fromJson(json);
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/DirectoryBuildpack.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -56,7 +56,7 @@ final class DirectoryBuildpack implements Buildpack {
 
 	private BuildpackCoordinates findBuildpackCoordinates(Path path) {
 		Path buildpackToml = path.resolve("buildpack.toml");
-		Assert.isTrue(Files.exists(buildpackToml),
+		Assert.state(Files.exists(buildpackToml),
 				() -> "Buildpack descriptor 'buildpack.toml' is required in buildpack '" + path + "'");
 		try {
 			try (InputStream inputStream = Files.newInputStream(buildpackToml)) {

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/docker/ExportedImageTar.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -127,7 +127,8 @@ class ExportedImageTar implements Closeable {
 					entry = tar.getNextEntry();
 				}
 				Assert.state(index != null || manifest != null,
-						"Exported image '%s' does not contain 'index.json' or 'manifest.json'".formatted(reference));
+						() -> "Exported image '%s' does not contain 'index.json' or 'manifest.json'"
+							.formatted(reference));
 				return (index != null) ? new IndexLayerArchiveFactory(tarFile, index)
 						: new ManifestLayerArchiveFactory(tarFile, manifest);
 			}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/docker/ssl/PemPrivateKeyParser.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -445,7 +445,7 @@ final class PemPrivateKeyParser {
 		public static final String PBES2_ALGORITHM = "PBES2";
 
 		static PKCS8EncodedKeySpec decrypt(byte[] bytes, String password) {
-			Assert.notNull(password, "Password is required for an encrypted private key");
+			Assert.state(password != null, "Password is required for an encrypted private key");
 			try {
 				EncryptedPrivateKeyInfo keyInfo = new EncryptedPrivateKeyInfo(bytes);
 				AlgorithmParameters algorithmParameters = keyInfo.getAlgParameters();

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/docker/transport/RemoteHttpClientTransport.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -35,6 +35,7 @@ import org.springframework.boot.buildpack.platform.docker.configuration.DockerHo
 import org.springframework.boot.buildpack.platform.docker.configuration.ResolvedDockerHost;
 import org.springframework.boot.buildpack.platform.docker.ssl.SslContextFactory;
 import org.springframework.util.Assert;
+import org.springframework.util.StringUtils;
 
 /**
  * {@link HttpClientTransport} that talks to a remote Docker.
@@ -85,8 +86,8 @@ final class RemoteHttpClientTransport extends HttpClientTransport {
 
 	private static TlsSocketStrategy getTlsSocketStrategy(DockerHost host, SslContextFactory sslContextFactory) {
 		String directory = host.getCertificatePath();
-		Assert.hasText(directory,
+		Assert.state(StringUtils.hasText(directory),
-				() -> "Docker host TLS verification requires trust material location to be specified with certificate path");
+				"Docker host TLS verification requires trust material location to be specified with certificate path");
 		SSLContext sslContext = sslContextFactory.forDirectory(directory);
 		return new DefaultClientTlsStrategy(sslContext);
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/BuilderBuildpackTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,7 +27,7 @@ import org.springframework.boot.buildpack.platform.docker.type.Layer;
 import org.springframework.boot.buildpack.platform.json.AbstractJsonTests;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -86,7 +86,7 @@ class BuilderBuildpackTests extends AbstractJsonTests {
 	@Test
 	void resolveWhenFullyQualifiedBuildpackWithVersionNotInBuilderThrowsException() {
 		BuildpackReference reference = BuildpackReference.of("urn:cnb:builder:example/buildpack1@1.2.3");
-		assertThatIllegalArgumentException().isThrownBy(() -> BuilderBuildpack.resolve(this.resolverContext, reference))
+		assertThatIllegalStateException().isThrownBy(() -> BuilderBuildpack.resolve(this.resolverContext, reference))
 			.withMessageContaining("'urn:cnb:builder:example/buildpack1@1.2.3'")
 			.withMessageContaining("not found in builder");
 	}
@@ -94,7 +94,7 @@ class BuilderBuildpackTests extends AbstractJsonTests {
 	@Test
 	void resolveWhenFullyQualifiedBuildpackWithoutVersionNotInBuilderThrowsException() {
 		BuildpackReference reference = BuildpackReference.of("urn:cnb:builder:example/buildpack1");
-		assertThatIllegalArgumentException().isThrownBy(() -> BuilderBuildpack.resolve(this.resolverContext, reference))
+		assertThatIllegalStateException().isThrownBy(() -> BuilderBuildpack.resolve(this.resolverContext, reference))
 			.withMessageContaining("'urn:cnb:builder:example/buildpack1'")
 			.withMessageContaining("not found in builder");
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/BuilderMetadataTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,6 +28,7 @@ import org.springframework.boot.buildpack.platform.json.AbstractJsonTests;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.assertj.core.api.Assertions.tuple;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
@@ -105,7 +106,7 @@ class BuilderMetadataTests extends AbstractJsonTests {
 		ImageConfig imageConfig = mock(ImageConfig.class);
 		given(image.getConfig()).willReturn(imageConfig);
 		given(imageConfig.getLabels()).willReturn(Collections.singletonMap("alpha", "a"));
-		assertThatIllegalArgumentException().isThrownBy(() -> BuilderMetadata.fromImage(image))
+		assertThatIllegalStateException().isThrownBy(() -> BuilderMetadata.fromImage(image))
 			.withMessage("No 'io.buildpacks.builder.metadata' label found in image config labels 'alpha'");
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/BuilderTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -517,7 +517,7 @@ class BuilderTests {
 		Builder builder = new Builder(BuildLog.to(out), docker, null);
 		BuildpackReference reference = BuildpackReference.of("urn:cnb:builder:example/buildpack@1.2.3");
 		BuildRequest request = getTestRequest().withBuildpacks(reference);
-		assertThatIllegalArgumentException().isThrownBy(() -> builder.build(request))
+		assertThatIllegalStateException().isThrownBy(() -> builder.build(request))
 			.withMessageContaining("'urn:cnb:builder:example/buildpack@1.2.3'")
 			.withMessageContaining("not found in builder");
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/BuildpackLayersMetadataTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,6 +27,7 @@ import org.springframework.boot.buildpack.platform.json.AbstractJsonTests;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -70,7 +71,7 @@ class BuildpackLayersMetadataTests extends AbstractJsonTests {
 		ImageConfig imageConfig = mock(ImageConfig.class);
 		given(image.getConfig()).willReturn(imageConfig);
 		given(imageConfig.getLabels()).willReturn(Collections.singletonMap("alpha", "a"));
-		assertThatIllegalArgumentException().isThrownBy(() -> BuildpackLayersMetadata.fromImage(image))
+		assertThatIllegalStateException().isThrownBy(() -> BuildpackLayersMetadata.fromImage(image))
 			.withMessage("No 'io.buildpacks.buildpack.layers' label found in image config labels 'alpha'");
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/BuildpackMetadataTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,6 +27,7 @@ import org.springframework.boot.buildpack.platform.json.AbstractJsonTests;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -64,7 +65,7 @@ class BuildpackMetadataTests extends AbstractJsonTests {
 		ImageConfig imageConfig = mock(ImageConfig.class);
 		given(image.getConfig()).willReturn(imageConfig);
 		given(imageConfig.getLabels()).willReturn(Collections.singletonMap("alpha", "a"));
-		assertThatIllegalArgumentException().isThrownBy(() -> BuildpackMetadata.fromImage(image))
+		assertThatIllegalStateException().isThrownBy(() -> BuildpackMetadata.fromImage(image))
 			.withMessage("No 'io.buildpacks.buildpackage.metadata' label found in image config labels 'alpha'");
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/DirectoryBuildpackTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -37,7 +37,7 @@ import org.junit.jupiter.api.condition.OS;
 import org.junit.jupiter.api.io.TempDir;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.assertj.core.api.Assertions.tuple;
 import static org.mockito.Mockito.mock;
 
@@ -89,8 +89,7 @@ class DirectoryBuildpackTests {
 	void resolveWhenDirectoryWithoutBuildpackTomlThrowsException() throws Exception {
 		Files.createDirectories(this.buildpackDir.toPath());
 		BuildpackReference reference = BuildpackReference.of(this.buildpackDir.toString());
-		assertThatIllegalArgumentException()
+		assertThatIllegalStateException().isThrownBy(() -> DirectoryBuildpack.resolve(this.resolverContext, reference))
-			.isThrownBy(() -> DirectoryBuildpack.resolve(this.resolverContext, reference))
 			.withMessageContaining("Buildpack descriptor 'buildpack.toml' is required")
 			.withMessageContaining(this.buildpackDir.getAbsolutePath());
 	}

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/build/ImageBuildpackTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -43,6 +43,7 @@ import org.springframework.boot.buildpack.platform.json.AbstractJsonTests;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.assertj.core.api.Assertions.fail;
 import static org.assertj.core.api.Assertions.tuple;
 import static org.mockito.ArgumentMatchers.any;
@@ -156,7 +157,7 @@ class ImageBuildpackTests extends AbstractJsonTests {
 		BuildpackResolverContext resolverContext = mock(BuildpackResolverContext.class);
 		given(resolverContext.fetchImage(any(), any())).willReturn(image);
 		BuildpackReference reference = BuildpackReference.of("docker://example/buildpack1:latest");
-		assertThatIllegalArgumentException().isThrownBy(() -> ImageBuildpack.resolve(resolverContext, reference))
+		assertThatIllegalStateException().isThrownBy(() -> ImageBuildpack.resolve(resolverContext, reference))
 			.withMessageContaining("No 'io.buildpacks.buildpackage.metadata' label found");
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/docker/transport/RemoteHttpClientTransportTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@ import org.springframework.boot.buildpack.platform.docker.configuration.Resolved
 import org.springframework.boot.buildpack.platform.docker.ssl.SslContextFactory;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -92,7 +92,7 @@ class RemoteHttpClientTransportTests {
 	void createIfPossibleWhenTlsVerifyWithMissingCertPathThrowsException() {
 		ResolvedDockerHost dockerHost = ResolvedDockerHost
 			.from(DockerHostConfiguration.forAddress("tcp://192.168.1.2:2376", true, null));
-		assertThatIllegalArgumentException().isThrownBy(() -> RemoteHttpClientTransport.createIfPossible(dockerHost))
+		assertThatIllegalStateException().isThrownBy(() -> RemoteHttpClientTransport.createIfPossible(dockerHost))
 			.withMessageContaining("Docker host TLS verification requires trust material");
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-cli/src/main/java/org/springframework/boot/cli/command/init/InitCommand.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -220,7 +220,7 @@ public class InitCommand extends OptionParsingCommand {
 
 		protected ProjectGenerationRequest createProjectGenerationRequest(OptionSet options) {
 			List<?> nonOptionArguments = new ArrayList<Object>(options.nonOptionArguments());
-			Assert.isTrue(nonOptionArguments.size() <= 1, "Only the target location may be specified");
+			Assert.state(nonOptionArguments.size() <= 1, "Only the target location may be specified");
 			ProjectGenerationRequest request = new ProjectGenerationRequest();
 			request.setServiceUrl(options.valueOf(this.target));
 			if (options.has(this.bootVersion)) {

spring-boot-project/spring-boot-tools/spring-boot-jarmode-tools/src/main/java/org/springframework/boot/jarmode/tools/IndexedJarStructure.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -128,13 +128,13 @@ class IndexedJarStructure implements JarStructure {
 	}
 
 	private String toStructureDependency(String libEntryName) {
-		Assert.state(libEntryName.startsWith(this.libLocation), "Invalid library location " + libEntryName);
+		Assert.state(libEntryName.startsWith(this.libLocation), () -> "Invalid library location " + libEntryName);
 		return libEntryName.substring(this.libLocation.length());
 	}
 
 	private static String getMandatoryAttribute(Manifest manifest, String attribute) {
 		String value = manifest.getMainAttributes().getValue(attribute);
-		Assert.state(value != null, "Manifest attribute '" + attribute + "' is mandatory");
+		Assert.state(value != null, () -> "Manifest attribute '" + attribute + "' is mandatory");
 		return value;
 	}
 

spring-boot-project/spring-boot-tools/spring-boot-jarmode-tools/src/main/java/org/springframework/boot/jarmode/tools/IndexedLayers.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -60,7 +60,7 @@ class IndexedLayers implements Layers {
 				this.layers.put(line.substring(3, line.length() - 2), contents);
 			}
 			else if (line.startsWith("  - ")) {
-				Assert.notNull(contents, "Contents must not be null. Check if the index file is malformed!");
+				Assert.state(contents != null, "Contents must not be null. Check if the index file is malformed!");
 				contents.add(line.substring(5, line.length() - 1));
 			}
 			else {

spring-boot-project/spring-boot-tools/spring-boot-properties-migrator/src/main/java/org/springframework/boot/context/properties/migrator/PropertyMigration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -154,7 +154,7 @@ class PropertyMigration {
 		ConfigurationPropertyName oldName = property.getName();
 		ConfigurationPropertyName oldPrefix = ConfigurationPropertyName.of(metadata.getId());
 		Assert.state(oldPrefix.isAncestorOf(oldName),
-				String.format("'%s' is not an ancestor of '%s'", oldPrefix, oldName));
+				() -> "'%s' is not an ancestor of '%s'".formatted(oldPrefix, oldName));
 		ConfigurationPropertyName newPrefix = ConfigurationPropertyName.of(replacement.getId());
 		return newPrefix.append(oldName.subName(oldPrefix.getNumberOfElements()));
 	}

spring-boot-project/spring-boot-tools/spring-boot-test-support/src/main/java/org/springframework/boot/testsupport/process/DisabledIfProcessUnavailableCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -69,7 +69,7 @@ class DisabledIfProcessUnavailableCondition implements ExecutionCondition {
 		ProcessBuilder processBuilder = new ProcessBuilder(command);
 		try {
 			Process process = processBuilder.start();
-			Assert.isTrue(process.waitFor(30, TimeUnit.SECONDS), "Process did not exit within 30 seconds");
+			Assert.state(process.waitFor(30, TimeUnit.SECONDS), "Process did not exit within 30 seconds");
 			Assert.state(process.exitValue() == 0, () -> "Process exited with %d".formatted(process.exitValue()));
 			process.destroy();
 		}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/SpringApplication.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -410,7 +410,7 @@ public class SpringApplication {
 		if (!AotDetector.useGeneratedArtifacts()) {
 			// Load the sources
 			Set<Object> sources = getAllSources();
-			Assert.notEmpty(sources, "Sources must not be empty");
+			Assert.state(!ObjectUtils.isEmpty(sources), "No sources defined");
 			load(context, sources.toArray(new Object[0]));
 		}
 		listeners.contextLoaded(context);
@@ -608,7 +608,7 @@ public class SpringApplication {
 		for (ApplicationContextInitializer initializer : getInitializers()) {
 			Class<?> requiredType = GenericTypeResolver.resolveTypeArgument(initializer.getClass(),
 					ApplicationContextInitializer.class);
-			Assert.isInstanceOf(requiredType, context, "Unable to call initializer.");
+			Assert.state(requiredType.isInstance(context), "Unable to call initializer");
 			initializer.initialize(context);
 		}
 	}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/SpringApplicationAotProcessor.java

@@ -65,7 +65,7 @@ public class SpringApplicationAotProcessor extends ContextAotProcessor {
 
 	public static void main(String[] args) throws Exception {
 		int requiredArgs = 6;
-		Assert.isTrue(args.length >= requiredArgs, () -> "Usage: " + SpringApplicationAotProcessor.class.getName()
+		Assert.state(args.length >= requiredArgs, () -> "Usage: " + SpringApplicationAotProcessor.class.getName()
 				+ " <applicationMainClass> <sourceOutput> <resourceOutput> <classOutput> <groupId> <artifactId> <originalArgs...>");
 		Class<?> application = Class.forName(args[0]);
 		Settings settings = Settings.builder()
@@ -110,7 +110,7 @@ public class SpringApplicationAotProcessor extends ContextAotProcessor {
 			}
 			catch (AbandonedRunException ex) {
 				ApplicationContext context = ex.getApplicationContext();
-				Assert.isInstanceOf(GenericApplicationContext.class, context,
+				Assert.state(context instanceof GenericApplicationContext,
 						() -> "AOT processing requires a GenericApplicationContext but got a "
 								+ context.getClass().getName());
 				return (GenericApplicationContext) context;

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigTreeConfigDataLocationResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -60,7 +60,7 @@ public class ConfigTreeConfigDataLocationResolver implements ConfigDataLocationR
 	}
 
 	private List<ConfigTreeConfigDataResource> resolve(String location) throws IOException {
-		Assert.isTrue(location.endsWith("/"),
+		Assert.state(location.endsWith("/"),
 				() -> String.format("Config tree location '%s' must end with '/'", location));
 		if (!this.resourceLoader.isPattern(location)) {
 			return Collections.singletonList(new ConfigTreeConfigDataResource(location));

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/metrics/buffering/BufferingApplicationStartup.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -91,7 +91,7 @@ public class BufferingApplicationStartup implements ApplicationStartup {
 	 * already.
 	 */
 	public void startRecording() {
-		Assert.state(this.events.isEmpty(), "Cannot restart recording once steps have been buffered.");
+		Assert.state(this.events.isEmpty(), "Cannot restart recording once steps have been buffered");
 		this.startTime = this.clock.instant();
 	}
 

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/convert/PeriodStyle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -264,7 +264,7 @@ public enum PeriodStyle {
 		}
 
 		private int intValue(Period value) {
-			Assert.notNull(this.intValue, () -> "intValue cannot be extracted from " + name());
+			Assert.state(this.intValue != null, () -> "intValue cannot be extracted from " + name());
 			return this.intValue.apply(value);
 		}
 

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/env/RandomValuePropertySource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -195,11 +195,11 @@ public class RandomValuePropertySource extends PropertySource<Random> {
 			String[] tokens = StringUtils.commaDelimitedListToStringArray(value);
 			T min = parse.apply(tokens[0]);
 			if (tokens.length == 1) {
-				Assert.isTrue(min.compareTo(zero) > 0, "Bound must be positive.");
+				Assert.state(min.compareTo(zero) > 0, "Bound must be positive.");
 				return new Range<>(value, zero, min);
 			}
 			T max = parse.apply(tokens[1]);
-			Assert.isTrue(min.compareTo(max) < 0, "Lower bound must be less than upper bound.");
+			Assert.state(min.compareTo(max) < 0, "Lower bound must be less than upper bound.");
 			return new Range<>(value, min, max);
 		}
 

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/jdbc/HikariCheckpointRestoreLifecycle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -61,9 +61,9 @@ public class HikariCheckpointRestoreLifecycle implements Lifecycle {
 
 	static {
 		Field closeConnectionExecutor = ReflectionUtils.findField(HikariPool.class, "closeConnectionExecutor");
-		Assert.notNull(closeConnectionExecutor, "Unable to locate closeConnectionExecutor for HikariPool");
+		Assert.state(closeConnectionExecutor != null, "Unable to locate closeConnectionExecutor for HikariPool");
-		Assert.isAssignable(ThreadPoolExecutor.class, closeConnectionExecutor.getType(),
+		Assert.state(ThreadPoolExecutor.class.isAssignableFrom(closeConnectionExecutor.getType()),
-				"Expected ThreadPoolExecutor for closeConnectionExecutor but found %s"
+				() -> "Expected ThreadPoolExecutor for closeConnectionExecutor but found %s"
 					.formatted(closeConnectionExecutor.getType()));
 		ReflectionUtils.makeAccessible(closeConnectionExecutor);
 		CLOSE_CONNECTION_EXECUTOR = closeConnectionExecutor;
@@ -104,7 +104,7 @@ public class HikariCheckpointRestoreLifecycle implements Lifecycle {
 		this.hasOpenConnections = (pool) -> {
 			ThreadPoolExecutor closeConnectionExecutor = (ThreadPoolExecutor) ReflectionUtils
 				.getField(CLOSE_CONNECTION_EXECUTOR, pool);
-			Assert.notNull(closeConnectionExecutor, "CloseConnectionExecutor was null");
+			Assert.state(closeConnectionExecutor != null, "'closeConnectionExecutor' was null");
 			return closeConnectionExecutor.getActiveCount() > 0;
 		};
 	}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/json/JsonValueWriter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -184,7 +184,7 @@ class JsonValueWriter {
 
 	<E> void writeElement(E element) {
 		ActiveSeries activeSeries = this.activeSeries.peek();
-		Assert.notNull(activeSeries, "No series has been started");
+		Assert.state(activeSeries != null, "No series has been started");
 		this.path = activeSeries.updatePath(this.path);
 		activeSeries.incrementIndexAndAddCommaIfRequired();
 		write(element);
@@ -223,7 +223,7 @@ class JsonValueWriter {
 		if (!isFilteredPath()) {
 			String processedName = processName(name.toString());
 			ActiveSeries activeSeries = this.activeSeries.peek();
-			Assert.notNull(activeSeries, "No series has been started");
+			Assert.state(activeSeries != null, "No series has been started");
 			activeSeries.incrementIndexAndAddCommaIfRequired();
 			Assert.state(activeSeries.addName(processedName),
 					() -> "The name '" + processedName + "' has already been written");

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/LoggerConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -190,7 +190,7 @@ public final class LoggerConfiguration {
 		 * @throws IllegalStateException if this is a {@link #isCustom() custom} level
 		 */
 		public LogLevel getLevel() {
-			Assert.state(this.logLevel != null, "Unable to provide LogLevel for '" + this.name + "'");
+			Assert.state(this.logLevel != null, () -> "Unable to provide LogLevel for '" + this.name + "'");
 			return this.logLevel;
 		}
 

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/LogbackLoggingSystem.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -409,7 +409,7 @@ public class LogbackLoggingSystem extends AbstractLoggingSystem implements BeanF
 
 	private LoggerContext getLoggerContext() {
 		ILoggerFactory factory = getLoggerFactory();
-		Assert.isInstanceOf(LoggerContext.class, factory,
+		Assert.state(factory instanceof LoggerContext,
 				() -> String.format(
 						"LoggerFactory is not a Logback LoggerContext but Logback is on "
 								+ "the classpath. Either remove Logback or the competing "

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/structured/StructuredLogFormatterFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -147,7 +147,7 @@ public class StructuredLogFormatterFactory<E> {
 	private void checkTypeArgument(Object formatter) {
 		Class<?> typeArgument = GenericTypeResolver.resolveTypeArgument(formatter.getClass(),
 				StructuredLogFormatter.class);
-		Assert.isTrue(this.logEventType.equals(typeArgument),
+		Assert.state(this.logEventType.equals(typeArgument),
 				() -> "Type argument of %s must be %s but was %s".formatted(formatter.getClass().getName(),
 						this.logEventType.getName(), (typeArgument != null) ? typeArgument.getName() : "null"));
 

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/r2dbc/EmbeddedDatabaseConnection.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -99,7 +99,7 @@ public enum EmbeddedDatabaseConnection {
 	 */
 	public static boolean isEmbedded(ConnectionFactory connectionFactory) {
 		OptionsCapableConnectionFactory optionsCapable = OptionsCapableConnectionFactory.unwrapFrom(connectionFactory);
-		Assert.notNull(optionsCapable,
+		Assert.state(optionsCapable != null,
 				() -> "Cannot determine database's type as ConnectionFactory is not options-capable. To be "
 						+ "options-capable, a ConnectionFactory should be created with "
 						+ ConnectionFactoryBuilder.class.getName());

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/ssl/pem/PemPrivateKeyParser.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -445,7 +445,7 @@ final class PemPrivateKeyParser {
 		public static final String PBES2_ALGORITHM = "PBES2";
 
 		static PKCS8EncodedKeySpec decrypt(byte[] bytes, String password) {
-			Assert.notNull(password, "Password is required for an encrypted private key");
+			Assert.state(password != null, "Password is required for an encrypted private key");
 			try {
 				EncryptedPrivateKeyInfo keyInfo = new EncryptedPrivateKeyInfo(bytes);
 				AlgorithmParameters algorithmParameters = keyInfo.getAlgParameters();

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/ssl/pem/PemSslStoreBundle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,6 +29,7 @@ import java.util.function.Supplier;
 import org.springframework.boot.ssl.SslStoreBundle;
 import org.springframework.core.style.ToStringCreator;
 import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 import org.springframework.util.function.SingletonSupplier;
 
@@ -89,7 +90,7 @@ public class PemSslStoreBundle implements SslStoreBundle {
 		}
 		try {
 			List<X509Certificate> certificates = pemSslStore.certificates();
-			Assert.notEmpty(certificates, "Certificates must not be empty");
+			Assert.state(!ObjectUtils.isEmpty(certificates), "Certificates must not be empty");
 			String alias = (pemSslStore.alias() != null) ? pemSslStore.alias() : DEFAULT_ALIAS;
 			KeyStore store = createKeyStore(pemSslStore.type());
 			PrivateKey privateKey = pemSslStore.privateKey();

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/util/Instantiator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -182,7 +182,7 @@ public class Instantiator<T> {
 	public <A> A getArg(Class<A> type) {
 		Assert.notNull(type, "'type' must not be null");
 		Function<Class<?>, Object> parameter = getAvailableParameter(type);
-		Assert.isTrue(parameter != null, "Unknown argument type " + type.getName());
+		Assert.state(parameter != null, "Unknown argument type " + type.getName());
 		return (A) parameter.apply(this.type);
 	}
 
@@ -193,7 +193,7 @@ public class Instantiator<T> {
 	private T instantiate(TypeSupplier typeSupplier) {
 		try {
 			Class<?> type = typeSupplier.get();
-			Assert.isAssignable(this.type, type);
+			Assert.state(this.type.isAssignableFrom(type), () -> type + " is not assignable to " + this.type);
 			return instantiate(type);
 		}
 		catch (Throwable ex) {

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/netty/NettyWebServer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -162,7 +162,7 @@ public class NettyWebServer implements WebServer {
 		}
 		if (this.resourceFactory != null) {
 			LoopResources resources = this.resourceFactory.getLoopResources();
-			Assert.notNull(resources, "No LoopResources: is ReactorResourceFactory not initialized yet?");
+			Assert.state(resources != null, "No LoopResources: is ReactorResourceFactory not initialized yet?");
 			server = server.runOn(resources);
 		}
 		if (this.lifecycleTimeout != null) {

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/embedded/undertow/UndertowWebServer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -175,7 +175,7 @@ public class UndertowWebServer implements WebServer {
 				this.closeables.add(closeable);
 			}
 			if (handler instanceof GracefulShutdownHandler shutdownHandler) {
-				Assert.isNull(this.gracefulShutdown, "Only a single GracefulShutdownHandler can be defined");
+				Assert.state(this.gracefulShutdown == null, "Only a single GracefulShutdownHandler can be defined");
 				this.gracefulShutdown = shutdownHandler;
 			}
 		}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/DelegatingFilterProxyRegistrationBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -95,8 +95,9 @@ public class DelegatingFilterProxyRegistrationBean extends AbstractFilterRegistr
 	}
 
 	private WebApplicationContext getWebApplicationContext() {
-		Assert.notNull(this.applicationContext, "ApplicationContext be injected");
+		Assert.state(this.applicationContext != null, "ApplicationContext has not been injected");
-		Assert.isInstanceOf(WebApplicationContext.class, this.applicationContext);
+		Assert.state(this.applicationContext instanceof WebApplicationContext,
+				"Injected ApplicationContext is not a WebApplicationContext");
 		return (WebApplicationContext) this.applicationContext;
 	}
 

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletComponentHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -52,7 +52,7 @@ abstract class ServletComponentHandler {
 		String[] value = (String[]) attributes.get("value");
 		String[] urlPatterns = (String[]) attributes.get("urlPatterns");
 		if (urlPatterns.length > 0) {
-			Assert.state(value.length == 0, "The urlPatterns and value attributes are mutually exclusive.");
+			Assert.state(value.length == 0, "The urlPatterns and value attributes are mutually exclusive");
 			return urlPatterns;
 		}
 		return value;

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/ServletRegistrationBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -168,7 +168,7 @@ public class ServletRegistrationBean<T extends Servlet> extends DynamicRegistrat
 
 	@Override
 	protected String getDescription() {
-		Assert.notNull(this.servlet, "Servlet must not be null");
+		Assert.state(this.servlet != null, "Unable to return description for null servlet");
 		return "servlet " + getServletName();
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/SimpleMainTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,7 +30,7 @@ import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link SpringApplication} main method.
@@ -45,7 +45,7 @@ class SimpleMainTests {
 
 	@Test
 	void emptyApplicationContext() {
-		assertThatIllegalArgumentException().isThrownBy(() -> SpringApplication.main(getArgs()));
+		assertThatIllegalStateException().isThrownBy(() -> SpringApplication.main(getArgs()));
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/SpringApplicationAotProcessorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,7 +26,6 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.context.aot.AbstractAotProcessor.Settings;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
@@ -84,8 +83,7 @@ class SpringApplicationAotProcessorTests {
 
 	@Test
 	void invokeMainWithMissingArguments() {
-		assertThatIllegalArgumentException()
+		assertThatIllegalStateException().isThrownBy(() -> SpringApplicationAotProcessor.main(new String[] { "Test" }))
-			.isThrownBy(() -> SpringApplicationAotProcessor.main(new String[] { "Test" }))
 			.withMessageContaining("Usage:");
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -213,8 +213,8 @@ class SpringApplicationTests {
 
 	@Test
 	void sourcesMustNotBeEmpty() {
-		assertThatIllegalArgumentException().isThrownBy(() -> new SpringApplication().run())
+		assertThatIllegalStateException().isThrownBy(() -> new SpringApplication().run())
-			.withMessageContaining("Sources must not be empty");
+			.withMessageContaining("No sources defined");
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/metrics/buffering/BufferingApplicationStartupTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -88,7 +88,7 @@ class BufferingApplicationStartupTests {
 		BufferingApplicationStartup applicationStartup = new BufferingApplicationStartup(2);
 		applicationStartup.start("first").end();
 		assertThatIllegalStateException().isThrownBy(applicationStartup::startRecording)
-			.withMessage("Cannot restart recording once steps have been buffered.");
+			.withMessage("Cannot restart recording once steps have been buffered");
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/env/RandomValuePropertySourceTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@ import org.springframework.core.env.SystemEnvironmentPropertySource;
 import org.springframework.mock.env.MockEnvironment;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.spy;
 
@@ -76,7 +76,7 @@ class RandomValuePropertySourceTests {
 
 	@Test
 	void intRangeWhenLowerBoundEqualsUpperBoundShouldFailWithIllegalArgumentException() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.source.getProperty("random.int[4,4]"))
+		assertThatIllegalStateException().isThrownBy(() -> this.source.getProperty("random.int[4,4]"))
 			.withMessage("Lower bound must be less than upper bound.");
 	}
 
@@ -95,13 +95,13 @@ class RandomValuePropertySourceTests {
 
 	@Test
 	void intMaxZero() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.source.getProperty("random.int(0)"))
+		assertThatIllegalStateException().isThrownBy(() -> this.source.getProperty("random.int(0)"))
 			.withMessage("Bound must be positive.");
 	}
 
 	@Test
 	void intNegativeBound() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.source.getProperty("random.int(-5)"))
+		assertThatIllegalStateException().isThrownBy(() -> this.source.getProperty("random.int(-5)"))
 			.withMessage("Bound must be positive.");
 	}
 
@@ -119,7 +119,7 @@ class RandomValuePropertySourceTests {
 
 	@Test
 	void longRangeWhenLowerBoundEqualsUpperBoundShouldFailWithIllegalArgumentException() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.source.getProperty("random.long[4,4]"))
+		assertThatIllegalStateException().isThrownBy(() -> this.source.getProperty("random.long[4,4]"))
 			.withMessage("Lower bound must be less than upper bound.");
 	}
 
@@ -138,13 +138,13 @@ class RandomValuePropertySourceTests {
 
 	@Test
 	void longMaxZero() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.source.getProperty("random.long(0)"))
+		assertThatIllegalStateException().isThrownBy(() -> this.source.getProperty("random.long(0)"))
 			.withMessage("Bound must be positive.");
 	}
 
 	@Test
 	void longNegativeBound() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.source.getProperty("random.long(-5)"))
+		assertThatIllegalStateException().isThrownBy(() -> this.source.getProperty("random.long(-5)"))
 			.withMessage("Bound must be positive.");
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/StructuredLoggingLayoutTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@ import org.springframework.test.util.ReflectionTestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link StructuredLogLayout}.
@@ -93,14 +94,14 @@ class StructuredLoggingLayoutTests extends AbstractStructuredLoggingTests {
 
 	@Test
 	void shouldCheckTypeArgument() {
-		assertThatIllegalArgumentException().isThrownBy(
+		assertThatIllegalStateException().isThrownBy(
 				() -> newBuilder().setFormat(CustomLog4j2StructuredLoggingFormatterWrongType.class.getName()).build())
 			.withMessageContaining("must be org.apache.logging.log4j.core.LogEvent but was java.lang.String");
 	}
 
 	@Test
 	void shouldCheckTypeArgumentWithRawType() {
-		assertThatIllegalArgumentException()
+		assertThatIllegalStateException()
 			.isThrownBy(
 					() -> newBuilder().setFormat(CustomLog4j2StructuredLoggingFormatterRawType.class.getName()).build())
 			.withMessageContaining("must be org.apache.logging.log4j.core.LogEvent but was null");

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/logback/StructuredLogEncoderTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -35,6 +35,7 @@ import org.springframework.mock.env.MockEnvironment;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link StructuredLogEncoder}.
@@ -113,7 +114,7 @@ class StructuredLogEncoderTests extends AbstractStructuredLoggingTests {
 
 	@Test
 	void shouldCheckTypeArgument() {
-		assertThatIllegalArgumentException().isThrownBy(() -> {
+		assertThatIllegalStateException().isThrownBy(() -> {
 			this.encoder.setFormat(CustomLogbackStructuredLoggingFormatterWrongType.class.getName());
 			this.encoder.start();
 		}).withMessageContaining("must be ch.qos.logback.classic.spi.ILoggingEvent but was java.lang.String");
@@ -121,7 +122,7 @@ class StructuredLogEncoderTests extends AbstractStructuredLoggingTests {
 
 	@Test
 	void shouldCheckTypeArgumentWithRawType() {
-		assertThatIllegalArgumentException().isThrownBy(() -> {
+		assertThatIllegalStateException().isThrownBy(() -> {
 			this.encoder.setFormat(CustomLogbackStructuredLoggingFormatterRawType.class.getName());
 			this.encoder.start();
 		}).withMessageContaining("must be ch.qos.logback.classic.spi.ILoggingEvent but was null");
@@ -133,8 +134,8 @@ class StructuredLogEncoderTests extends AbstractStructuredLoggingTests {
 			this.encoder.setFormat("does-not-exist");
 			this.encoder.start();
 		})
-			.withMessageContaining(
+			.withMessageContaining("Unknown format 'does-not-exist'. Values can be a valid fully-qualified "
-					"Unknown format 'does-not-exist'. Values can be a valid fully-qualified class name or one of the common formats: [ecs, gelf, logstash]");
+					+ "class name or one of the common formats: [ecs, gelf, logstash]");
 	}
 
 	private String encode(LoggingEvent event) {

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/structured/StructuredLogFormatterFactoryTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,6 +31,7 @@ import org.springframework.mock.env.MockEnvironment;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
@@ -83,7 +84,7 @@ class StructuredLogFormatterFactoryTests {
 
 	@Test
 	void getUsingClassNameWhenHasGenericMismatch() {
-		assertThatIllegalArgumentException().isThrownBy(() -> this.factory.get(DifferentFormatter.class.getName()))
+		assertThatIllegalStateException().isThrownBy(() -> this.factory.get(DifferentFormatter.class.getName()))
 			.withMessage("Type argument of org.springframework.boot.logging.structured."
 					+ "StructuredLogFormatterFactoryTests$DifferentFormatter "
 					+ "must be org.springframework.boot.logging.structured."

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/r2dbc/EmbeddedDatabaseConnectionTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,7 +29,7 @@ import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link EmbeddedDatabaseConnection}.
@@ -85,7 +85,7 @@ class EmbeddedDatabaseConnectionTests {
 
 	@Test
 	void whenConnectionFactoryIsNotOptionsCapableThenIsEmbeddedThrows() {
-		assertThatIllegalArgumentException()
+		assertThatIllegalStateException()
 			.isThrownBy(() -> EmbeddedDatabaseConnection
 				.isEmbedded(ConnectionFactories.get("r2dbc:pool:h2:mem:///" + UUID.randomUUID())))
 			.withMessage("Cannot determine database's type as ConnectionFactory is not options-capable. To be "

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/util/InstantiatorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -140,7 +140,7 @@ class InstantiatorTests {
 	@Test
 	void getArgWhenUnknownThrowsException() {
 		Instantiator<?> instantiator = createInstantiator(WithMultipleConstructors.class);
-		assertThatIllegalArgumentException().isThrownBy(() -> instantiator.getArg(InputStream.class))
+		assertThatIllegalStateException().isThrownBy(() -> instantiator.getArg(InputStream.class))
 			.withMessageStartingWith("Unknown argument type");
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/ServletRegistrationBeanTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -135,8 +135,8 @@ class ServletRegistrationBeanTests {
 	@Test
 	void setServletMustNotBeNull() {
 		ServletRegistrationBean<MockServlet> bean = new ServletRegistrationBean<>();
-		assertThatIllegalArgumentException().isThrownBy(() -> bean.onStartup(this.servletContext))
+		assertThatIllegalStateException().isThrownBy(() -> bean.onStartup(this.servletContext))
-			.withMessageContaining("Servlet must not be null");
+			.withMessageContaining("Unable to return description for null servlet");
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/WebFilterHandlerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -130,7 +130,7 @@ class WebFilterHandlerTests {
 	void urlPatternsDeclaredTwice() {
 		assertThatIllegalStateException()
 			.isThrownBy(() -> handleBeanDefinitionForClass(UrlPatternsDeclaredTwiceFilter.class))
-			.withMessageContaining("The urlPatterns and value attributes are mutually exclusive.");
+			.withMessageContaining("The urlPatterns and value attributes are mutually exclusive");
 	}
 
 	private AnnotatedBeanDefinition createBeanDefinition(Class<?> filterClass) throws IOException {

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/WebServletHandlerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -105,7 +105,7 @@ class WebServletHandlerTests {
 	void urlPatternsDeclaredTwice() {
 		assertThatIllegalStateException()
 			.isThrownBy(() -> handleBeanDefinitionForClass(UrlPatternsDeclaredTwiceServlet.class))
-			.withMessageContaining("The urlPatterns and value attributes are mutually exclusive.");
+			.withMessageContaining("The urlPatterns and value attributes are mutually exclusive");
 	}
 
 	private AnnotatedBeanDefinition createBeanDefinition(Class<?> servletClass) throws IOException {

spring-boot-system-tests/spring-boot-image-tests/src/systemTest/java/org/springframework/boot/image/junit/GradleBuildInjectionExtension.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -40,7 +40,7 @@ public class GradleBuildInjectionExtension implements BeforeEachCallback {
 		this.gradleBuild = new GradleBuild();
 		this.gradleBuild.gradleVersion(GradleVersions.minimumCompatible());
 		String bootVersion = System.getProperty("springBootVersion");
-		Assert.notNull(bootVersion, "Property 'springBootVersion' must be set in build environment");
+		Assert.state(bootVersion != null, "Property 'springBootVersion' must be set in build environment");
 		this.gradleBuild.bootVersion(bootVersion);
 	}