Allow binding number to DataSize

Closes gh-14294

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

@@ -100,6 +100,7 @@ public class ApplicationConversionService extends FormattingConversionService {
 		registry.addConverter(new NumberToDurationConverter());
 		registry.addConverter(new DurationToNumberConverter());
 		registry.addConverter(new StringToDataSizeConverter());
+		registry.addConverter(new NumberToDataSizeConverter());
 		registry.addConverterFactory(new StringToEnumIgnoringCaseConverterFactory());
 	}
 

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

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2012-2018 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.convert;
+
+import java.util.Collections;
+import java.util.Set;
+
+import org.springframework.core.convert.TypeDescriptor;
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.core.convert.converter.GenericConverter;
+import org.springframework.util.unit.DataSize;
+
+/**
+ * {@link Converter} to convert from a {@link Number} to a {@link DataSize}.
+ *
+ * @author Stephane Nicoll
+ * @see DataSizeUnit
+ */
+final class NumberToDataSizeConverter implements GenericConverter {
+
+	private final StringToDataSizeConverter delegate = new StringToDataSizeConverter();
+
+	@Override
+	public Set<ConvertiblePair> getConvertibleTypes() {
+		return Collections.singleton(new ConvertiblePair(Number.class, DataSize.class));
+	}
+
+	@Override
+	public Object convert(Object source, TypeDescriptor sourceType,
+			TypeDescriptor targetType) {
+		return this.delegate.convert((source != null) ? source.toString() : null,
+				TypeDescriptor.valueOf(String.class), targetType);
+	}
+
+}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/convert/NumberToDataSizeConverterTests.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright 2012-2018 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.convert;
+
+import java.util.Collections;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+
+import org.springframework.core.annotation.AnnotationUtils;
+import org.springframework.core.convert.ConversionService;
+import org.springframework.core.convert.TypeDescriptor;
+import org.springframework.util.unit.DataSize;
+import org.springframework.util.unit.DataUnit;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link NumberToDataSizeConverter}.
+ *
+ * @author Stephane Nicoll
+ */
+@RunWith(Parameterized.class)
+public class NumberToDataSizeConverterTests {
+
+	private final ConversionService conversionService;
+
+	public NumberToDataSizeConverterTests(String name,
+			ConversionService conversionService) {
+		this.conversionService = conversionService;
+	}
+
+	@Test
+	public void convertWhenSimpleWithoutSuffixShouldReturnDataSize() {
+		assertThat(convert(10)).isEqualTo(DataSize.ofBytes(10));
+		assertThat(convert(+10)).isEqualTo(DataSize.ofBytes(10));
+		assertThat(convert(-10)).isEqualTo(DataSize.ofBytes(-10));
+	}
+
+	@Test
+	public void convertWhenSimpleWithoutSuffixButWithAnnotationShouldReturnDataSize() {
+		assertThat(convert(10, DataUnit.KILOBYTES)).isEqualTo(DataSize.ofKiloBytes(10));
+		assertThat(convert(+10, DataUnit.KILOBYTES)).isEqualTo(DataSize.ofKiloBytes(10));
+		assertThat(convert(-10, DataUnit.KILOBYTES)).isEqualTo(DataSize.ofKiloBytes(-10));
+	}
+
+	private DataSize convert(Integer source) {
+		return this.conversionService.convert(source, DataSize.class);
+	}
+
+	@SuppressWarnings({ "rawtypes", "unchecked" })
+	private DataSize convert(Integer source, DataUnit defaultUnit) {
+		TypeDescriptor targetType = mock(TypeDescriptor.class);
+		if (defaultUnit != null) {
+			DataSizeUnit unitAnnotation = AnnotationUtils.synthesizeAnnotation(
+					Collections.singletonMap("value", defaultUnit), DataSizeUnit.class,
+					null);
+			given(targetType.getAnnotation(DataSizeUnit.class))
+					.willReturn(unitAnnotation);
+		}
+		given(targetType.getType()).willReturn((Class) DataSize.class);
+		return (DataSize) this.conversionService.convert(source,
+				TypeDescriptor.forObject(source), targetType);
+	}
+
+	@Parameterized.Parameters(name = "{0}")
+	public static Iterable<Object[]> conversionServices() {
+		return new ConversionServiceParameters(new NumberToDataSizeConverter());
+	}
+
+}