Support of Lombok annotated ConfigurationProperties

Previously, no configuration properties were discovered on a class using
lombok instead of regular getters/setters.

This commit adds a support for some of the lombok annotations,
specifically that is @Data, @Getter and @Setter. Provides the same
semantic as what lombok is generating.

Closes gh-2114

spring-boot-docs/src/main/asciidoc/appendix-configuration-metadata.adoc

@@ -190,6 +190,10 @@ will be used to populate the `description` attribute.
 NOTE: You should only use simple text with `@ConfigurationProperties` field Javadoc since
 they are not processed before being added to the JSON.
 
+Properties are discovered via the presence of standard getters and setters with special
+handling for collection types (that will be detected even if only a getter is present). The
+annotation processor also supports the use of the `@Data`, `@Getter` and `@Setter` lombok
+annotations.
 
 
 [[configuration-metadata-nested-properties]]

spring-boot-parent/pom.xml

@@ -191,6 +191,11 @@
 				<artifactId>json</artifactId>
 				<version>${json.version}</version>
 			</dependency>
+			<dependency>
+				<groupId>org.projectlombok</groupId>
+				<artifactId>lombok</artifactId>
+				<version>1.12.6</version>
+			</dependency>
 			<dependency>
 				<groupId>org.zeroturnaround</groupId>
 				<artifactId>zt-zip</artifactId>

spring-boot-tools/spring-boot-configuration-processor/pom.xml

@@ -23,6 +23,12 @@
 			<groupId>org.json</groupId>
 			<artifactId>json</artifactId>
 		</dependency>
+
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 	<build>
 		<plugins>

spring-boot-tools/spring-boot-configuration-processor/src/main/java/org/springframework/boot/configurationprocessor/ConfigurationMetadataAnnotationProcessor.java

@@ -40,6 +40,7 @@ import javax.lang.model.element.Modifier;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.element.VariableElement;
 import javax.lang.model.type.TypeKind;
+import javax.lang.model.type.TypeMirror;
 import javax.lang.model.util.Elements;
 import javax.tools.Diagnostic.Kind;
 import javax.tools.FileObject;
@@ -69,6 +70,12 @@ public class ConfigurationMetadataAnnotationProcessor extends AbstractProcessor
 	static final String NESTED_CONFIGURATION_PROPERTY_ANNOTATION = "org.springframework.boot."
 			+ "context.properties.NestedConfigurationProperty";
 
+	static final String LOMBOK_DATA_ANNOTATION = "lombok.Data";
+
+	static final String LOMBOK_GETTER_ANNOTATION = "lombok.Getter";
+
+	static final String LOMBOK_SETTER_ANNOTATION = "lombok.Setter";
+
 	private ConfigurationMetadata metadata;
 
 	private TypeUtils typeUtils;
@@ -157,6 +164,7 @@ public class ConfigurationMetadataAnnotationProcessor extends AbstractProcessor
 		TypeElementMembers members = new TypeElementMembers(this.processingEnv, element);
 		Map<String, Object> fieldValues = getFieldValues(element);
 		processSimpleTypes(prefix, element, members, fieldValues);
+		processLombokTypes(prefix, element, members, fieldValues);
 		processNestedTypes(prefix, element, members);
 	}
 
@@ -177,15 +185,14 @@ public class ConfigurationMetadataAnnotationProcessor extends AbstractProcessor
 			ExecutableElement getter = entry.getValue();
 			ExecutableElement setter = members.getPublicSetters().get(name);
 			VariableElement field = members.getFields().get(name);
-			Element returnType = this.processingEnv.getTypeUtils().asElement(
-					getter.getReturnType());
-			boolean isExcluded = this.typeExcludeFilter.isExcluded(getter
-					.getReturnType());
-			boolean isNested = isNested(returnType, field, element);
-			boolean isCollection = this.typeUtils.isCollectionOrMap(getter
-					.getReturnType());
+			TypeMirror returnType = getter.getReturnType();
+			Element returnTypeElement = this.processingEnv.getTypeUtils().asElement(
+					returnType);
+			boolean isExcluded = this.typeExcludeFilter.isExcluded(returnType);
+			boolean isNested = isNested(returnTypeElement, field, element);
+			boolean isCollection = this.typeUtils.isCollectionOrMap(returnType);
 			if (!isExcluded && !isNested && (setter != null || isCollection)) {
-				String dataType = this.typeUtils.getType(getter.getReturnType());
+				String dataType = this.typeUtils.getType(returnType);
 				String sourceType = this.typeUtils.getType(element);
 				String description = this.typeUtils.getJavaDoc(field);
 				Object defaultValue = fieldValues.get(name);
@@ -198,6 +205,48 @@ public class ConfigurationMetadataAnnotationProcessor extends AbstractProcessor
 		}
 	}
 
+	private void processLombokTypes(String prefix, TypeElement element,
+			TypeElementMembers members, Map<String, Object> fieldValues) {
+		for (Map.Entry<String, VariableElement> entry : members.getFields()
+				.entrySet()) {
+			String name = entry.getKey();
+			VariableElement field = entry.getValue();
+			if (!isLombokField(field, element)) {
+				continue;
+			}
+			TypeMirror returnType = field.asType();
+			Element returnTypeElement = this.processingEnv.getTypeUtils().asElement(
+					returnType);
+			boolean isExcluded = this.typeExcludeFilter.isExcluded(returnType);
+			boolean isNested = isNested(returnTypeElement, field, element);
+			boolean isCollection = this.typeUtils.isCollectionOrMap(returnType);
+			boolean hasSetter = hasLombokSetter(field, element);
+			if (!isExcluded && !isNested && (hasSetter || isCollection)) {
+				String dataType = this.typeUtils.getType(returnType);
+				String sourceType = this.typeUtils.getType(element);
+				String description = this.typeUtils.getJavaDoc(field);
+				Object defaultValue = fieldValues.get(name);
+				boolean deprecated = hasDeprecateAnnotation(field)
+						|| hasDeprecateAnnotation(element);
+				this.metadata.add(ItemMetadata.newProperty(prefix, name, dataType,
+						sourceType, null, description, defaultValue, deprecated));
+			}
+		}
+	}
+
+	private boolean isLombokField(VariableElement field, TypeElement element) {
+		return hasAnnotation(field, LOMBOK_GETTER_ANNOTATION)
+				|| hasAnnotation(element, LOMBOK_GETTER_ANNOTATION)
+				|| hasAnnotation(element, LOMBOK_DATA_ANNOTATION);
+	}
+
+	private boolean hasLombokSetter(VariableElement field, TypeElement element) {
+		return !field.getModifiers().contains(Modifier.FINAL) && (
+				hasAnnotation(field, LOMBOK_SETTER_ANNOTATION)
+						|| hasAnnotation(element, LOMBOK_SETTER_ANNOTATION)
+						|| hasAnnotation(element, LOMBOK_DATA_ANNOTATION));
+	}
+
 	private void processNestedTypes(String prefix, TypeElement element,
 			TypeElementMembers members) {
 		for (Map.Entry<String, ExecutableElement> entry : members.getPublicGetters()
@@ -223,7 +272,7 @@ public class ConfigurationMetadataAnnotationProcessor extends AbstractProcessor
 
 	private boolean isNested(Element returnType, VariableElement field,
 			TypeElement element) {
-		if (getAnnotation(field, nestedConfigurationPropertyAnnotation()) != null) {
+		if (hasAnnotation(field, nestedConfigurationPropertyAnnotation())) {
 			return true;
 		}
 		return this.typeUtils.isEnclosedIn(returnType, element)
@@ -231,7 +280,11 @@ public class ConfigurationMetadataAnnotationProcessor extends AbstractProcessor
 	}
 
 	private boolean hasDeprecateAnnotation(Element element) {
-		return getAnnotation(element, "java.lang.Deprecated") != null;
+		return hasAnnotation(element, "java.lang.Deprecated");
+	}
+
+	private boolean hasAnnotation(Element element, String type) {
+		return getAnnotation(element, type) != null;
 	}
 
 	private AnnotationMirror getAnnotation(Element element, String type) {

spring-boot-tools/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationprocessor/ConfigurationMetadataAnnotationProcessorTests.java

@@ -17,7 +17,6 @@
 package org.springframework.boot.configurationprocessor;
 
 import java.io.IOException;
-
 import javax.annotation.processing.SupportedAnnotationTypes;
 import javax.annotation.processing.SupportedSourceVersion;
 import javax.lang.model.SourceVersion;
@@ -25,7 +24,11 @@ import javax.lang.model.SourceVersion;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
+
 import org.springframework.boot.configurationprocessor.metadata.ConfigurationMetadata;
+import org.springframework.boot.configurationsample.lombok.LombokSimpleDataProperties;
+import org.springframework.boot.configurationsample.lombok.LombokExplicitProperties;
+import org.springframework.boot.configurationsample.lombok.LombokSimpleProperties;
 import org.springframework.boot.configurationsample.method.EmptyTypeMethodConfig;
 import org.springframework.boot.configurationsample.method.InvalidMethodConfig;
 import org.springframework.boot.configurationsample.method.MethodAndClassConfig;
@@ -286,13 +289,49 @@ public class ConfigurationMetadataAnnotationProcessorTests {
 		assertThat(metadata, not(containsProperty("excluded.writer-array")));
 	}
 
+	@Test
+	public void lombokDataProperties() throws Exception {
+		ConfigurationMetadata metadata = compile(LombokSimpleDataProperties.class);
+		assertSimpleLombokProperties(metadata, LombokSimpleDataProperties.class, "data");
+	}
+
+	@Test
+	public void lombokSimpleProperties() throws Exception {
+		ConfigurationMetadata metadata = compile(LombokSimpleProperties.class);
+		assertSimpleLombokProperties(metadata, LombokSimpleProperties.class, "simple");
+	}
+
+	@Test
+	public void lombokExplicitProperties() throws Exception {
+		ConfigurationMetadata metadata = compile(LombokExplicitProperties.class);
+		assertSimpleLombokProperties(metadata, LombokExplicitProperties.class, "explicit");
+	}
+
+	private void assertSimpleLombokProperties(ConfigurationMetadata metadata, Class<?> source, String prefix) {
+		assertThat(metadata, containsGroup(prefix).fromSource(source));
+		assertThat(metadata, not(containsProperty(prefix + ".id")));
+		assertThat(
+				metadata,
+				containsProperty(prefix + ".name", String.class)
+						.fromSource(source)
+						.withDescription("Name description."));
+		assertThat(metadata, containsProperty(prefix + ".description"));
+		assertThat(metadata, containsProperty(prefix + ".counter"));
+		assertThat(metadata,
+				containsProperty(prefix + ".number").fromSource(source)
+						.withDefaultValue(is(0))
+						.withDeprecated());
+		assertThat(metadata, containsProperty(prefix + ".items"));
+		assertThat(metadata, not(containsProperty(prefix + ".ignored")));
+	}
+
 	private ConfigurationMetadata compile(Class<?>... types) throws IOException {
 		TestConfigurationMetadataAnnotationProcessor processor = new TestConfigurationMetadataAnnotationProcessor();
 		new TestCompiler(this.temporaryFolder).getTask(types).call(processor);
 		return processor.getMetadata();
 	}
 
-	@SupportedAnnotationTypes({ "*" })
+	@SupportedAnnotationTypes({"*"})
 	@SupportedSourceVersion(SourceVersion.RELEASE_6)
 	private static class TestConfigurationMetadataAnnotationProcessor extends
 			ConfigurationMetadataAnnotationProcessor {

spring-boot-tools/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationsample/lombok/LombokExplicitProperties.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2012-2014 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.configurationsample.lombok;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import lombok.Getter;
+import lombok.Setter;
+
+import org.springframework.boot.configurationsample.ConfigurationProperties;
+
+/**
+ * Configuration properties using lombok @Getter/@Setter at field level.
+ *
+ * @author Stephane Nicoll
+ */
+@ConfigurationProperties(prefix = "explicit")
+public class LombokExplicitProperties {
+
+	@Getter
+	private final String id = "super-id";
+
+	/**
+	 * Name description.
+	 */
+	@Getter @Setter
+	private String name;
+
+	@Getter @Setter
+	private String description;
+
+	@Getter @Setter
+	private Integer counter;
+
+	@Deprecated @Getter @Setter
+	private Integer number = 0;
+
+	@Getter
+	private final List<String> items = new ArrayList<String>();
+
+	// Should be ignored if no annotation is set
+	private String ignored;
+
+}

spring-boot-tools/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationsample/lombok/LombokSimpleDataProperties.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2012-2014 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.configurationsample.lombok;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import lombok.Data;
+
+import org.springframework.boot.configurationsample.ConfigurationProperties;
+
+/**
+ * Configuration properties using lombok @Data.
+ *
+ * @author Stephane Nicoll
+ */
+@Data
+@ConfigurationProperties(prefix = "data")
+public class LombokSimpleDataProperties {
+
+	private final String id = "super-id";
+
+	/**
+	 * Name description.
+	 */
+	private String name;
+
+	private String description;
+
+	private Integer counter;
+
+	@Deprecated
+	private Integer number = 0;
+
+	private final List<String> items = new ArrayList<String>();
+
+	private final String ignored = "foo";
+
+}

spring-boot-tools/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationsample/lombok/LombokSimpleProperties.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2012-2014 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.configurationsample.lombok;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import lombok.Getter;
+import lombok.Setter;
+
+import org.springframework.boot.configurationsample.ConfigurationProperties;
+
+/**
+ * Configuration properties using lombok @Getter/@Setter at class level.
+ *
+ * @author Stephane Nicoll
+ */
+@Getter
+@Setter
+@ConfigurationProperties(prefix = "simple")
+public class LombokSimpleProperties {
+
+	private final String id = "super-id";
+
+	/**
+	 * Name description.
+	 */
+	private String name;
+
+	private String description;
+
+	private Integer counter;
+
+	@Deprecated
+	private Integer number = 0;
+
+	private final List<String> items = new ArrayList<String>();
+
+	private final String ignored = "foo";
+
+}