Use RelaxedDataBinder for excludes

Update `EnableAutoConfigurationImportSelector` to directly use the
RelaxedDataBinder when obtaining excludes. This removes the need for
the additional getProperties method on RelaxedPropertyResolver.

See gh-4352

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/EnableAutoConfigurationImportSelector.java

@@ -30,6 +30,8 @@ import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.boot.autoconfigure.condition.ConditionEvaluationReport;
+import org.springframework.boot.bind.PropertySourcesPropertyValues;
+import org.springframework.boot.bind.RelaxedDataBinder;
 import org.springframework.boot.bind.RelaxedPropertyResolver;
 import org.springframework.context.EnvironmentAware;
 import org.springframework.context.ResourceLoaderAware;
@@ -37,6 +39,7 @@ import org.springframework.context.annotation.DeferredImportSelector;
 import org.springframework.core.Ordered;
 import org.springframework.core.annotation.AnnotationAttributes;
 import org.springframework.core.annotation.Order;
+import org.springframework.core.env.ConfigurableEnvironment;
 import org.springframework.core.env.Environment;
 import org.springframework.core.io.ResourceLoader;
 import org.springframework.core.io.support.SpringFactoriesLoader;
@@ -151,14 +154,18 @@ public class EnableAutoConfigurationImportSelector implements DeferredImportSele
 	}
 
 	private List<String> getExcludeAutoConfigurationsProperty() {
+		if (getEnvironment() instanceof ConfigurableEnvironment) {
+			Excludes excludes = new Excludes();
+			RelaxedDataBinder binder = new RelaxedDataBinder(excludes,
+					"spring.autoconfigure.");
+			binder.bind(new PropertySourcesPropertyValues(
+					((ConfigurableEnvironment) getEnvironment()).getPropertySources()));
+			return excludes.getExclude();
+		}
 		RelaxedPropertyResolver resolver = new RelaxedPropertyResolver(getEnvironment(),
 				"spring.autoconfigure.");
-		Collection<Object> raw = resolver.getProperties("exclude");
-		List<String> values = new ArrayList<String>();
-		for (Object r : raw) {
-			values.add(r.toString());
-		}
-		return values;
+		String[] exclude = resolver.getProperty("exclude", String[].class);
+		return (Arrays.asList(exclude == null ? new String[0] : exclude));
 	}
 
 	private List<String> sort(List<String> configurations) throws IOException {
@@ -221,4 +228,21 @@ public class EnableAutoConfigurationImportSelector implements DeferredImportSele
 		return this.resourceLoader;
 	}
 
+	/**
+	 * Bindable object used to get excludes.
+	 */
+	static class Excludes {
+
+		private List<String> exclude = new ArrayList<String>();
+
+		public List<String> getExclude() {
+			return this.exclude;
+		}
+
+		public void setExclude(List<String> excludes) {
+			this.exclude = excludes;
+		}
+
+	}
+
 }

spring-boot/src/main/java/org/springframework/boot/bind/RelaxedPropertyResolver.java

@@ -16,9 +16,6 @@
 
 package org.springframework.boot.bind;
 
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
 import java.util.Map;
 
 import org.springframework.core.env.ConfigurableEnvironment;
@@ -131,21 +128,6 @@ public class RelaxedPropertyResolver implements PropertyResolver {
 				"Unable to resolve placeholders with relaxed properties");
 	}
 
-	/**
-	 * Return the property values associated with the given key, or an empty
-	 * list if the key cannot be resolved.
-	 * @param key the property name to resolve
-	 * @return the property values for that key
-	 */
-	public List<Object> getProperties(String key) {
-		Object[] singular = getProperty(key, Object[].class);
-		if (singular != null) {
-			return Arrays.asList(singular);
-		}
-		Map<String, Object> subProperties = getSubProperties(key);
-		return new ArrayList<Object>(subProperties.values());
-	}
-
 	/**
 	 * Return a Map of all values from all underlying properties that start with the
 	 * specified key. NOTE: this method can only be used if the underlying resolver is a

spring-boot/src/test/java/org/springframework/boot/bind/RelaxedPropertyResolverTests.java

@@ -17,7 +17,6 @@
 package org.springframework.boot.bind;
 
 import java.util.LinkedHashMap;
-import java.util.List;
 import java.util.Map;
 import java.util.Properties;
 
@@ -31,7 +30,6 @@ import org.springframework.core.env.MutablePropertySources;
 import org.springframework.core.env.PropertiesPropertySource;
 import org.springframework.core.env.StandardEnvironment;
 
-import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.nullValue;
 import static org.junit.Assert.assertEquals;
@@ -169,34 +167,6 @@ public class RelaxedPropertyResolverTests {
 		assertThat(this.resolver.getProperty("foo-bar"), equalTo("spam"));
 	}
 
-	@Test
-	public void commaSeparatedProperties() throws Exception {
-		this.source.put("x.y.foo", "1,2");
-		this.resolver = new RelaxedPropertyResolver(this.environment, "x.y.");
-		List<Object> properties = this.resolver.getProperties("foo");
-		assertThat(properties.size(), equalTo(2));
-		assertThat(properties, contains((Object) "1", (Object) "2"));
-	}
-
-	@Test
-	public void commaSeparatedPropertiesSingleValue() throws Exception {
-		this.source.put("x.y.foo", "1");
-		this.resolver = new RelaxedPropertyResolver(this.environment, "x.y.");
-		List<Object> properties = this.resolver.getProperties("foo");
-		assertThat(properties.size(), equalTo(1));
-		assertThat(properties, contains((Object) "1"));
-	}
-
-	@Test
-	public void indexedProperties() throws Exception {
-		this.source.put("x.y.foo[0]", "1");
-		this.source.put("x.y.foo[1]", "2");
-		this.resolver = new RelaxedPropertyResolver(this.environment, "x.y.");
-		List<Object> properties = this.resolver.getProperties("foo");
-		assertThat(properties.size(), equalTo(2));
-		assertThat(properties, contains((Object) "1", (Object) "2"));
-	}
-
 	@Test
 	public void subProperties() throws Exception {
 		this.source.put("x.y.my-sub.a.b", "1");