@Jacksonized: modify builders that they can be used by Jackson

1 files changed, 198 insertions, 0 deletions

diff --git a/src/core/lombok/javac/handlers/HandleJacksonized.java b/src/core/lombok/javac/handlers/HandleJacksonized.java
new file mode 100644
index 00000000..889dd27d
--- /dev/null
+++ b/src/core/lombok/javac/handlers/HandleJacksonized.java
@@ -0,0 +1,198 @@
+/*
+ * Copyright (C) 2020 The Project Lombok Authors.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.javac.handlers;
+
+import static lombok.javac.handlers.JavacHandlerUtil.*;
+
+import org.mangosdk.spi.ProviderFor;
+
+import com.sun.tools.javac.code.Flags;
+import com.sun.tools.javac.tree.JCTree;
+import com.sun.tools.javac.tree.JCTree.JCAnnotation;
+import com.sun.tools.javac.tree.JCTree.JCClassDecl;
+import com.sun.tools.javac.tree.JCTree.JCExpression;
+import com.sun.tools.javac.tree.JCTree.JCFieldAccess;
+import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
+import com.sun.tools.javac.tree.JCTree.JCTypeApply;
+import com.sun.tools.javac.tree.JCTree.JCTypeParameter;
+import com.sun.tools.javac.util.List;
+import com.sun.tools.javac.util.ListBuffer;
+
+import lombok.Builder;
+import lombok.ConfigurationKeys;
+import lombok.core.AST.Kind;
+import lombok.core.AnnotationValues;
+import lombok.core.HandlerPriority;
+import lombok.core.handlers.HandlerUtil;
+import lombok.experimental.SuperBuilder;
+import lombok.extern.jackson.Jacksonized;
+import lombok.javac.JavacAnnotationHandler;
+import lombok.javac.JavacNode;
+import lombok.javac.JavacTreeMaker;
+
+/**
+ * This (javac) handler deals with {@code @Jacksonized} modifying the (already
+ * generated) {@code @Builder} or {@code @SuperBuilder} to conform to Jackson's
+ * needs for builders.
+ */
+@ProviderFor(JavacAnnotationHandler.class)
+@HandlerPriority(-512) // Above Handle(Super)Builder's level (builders must be already generated).
+public class HandleJacksonized extends JavacAnnotationHandler<Jacksonized> {
+	
+	@Override public void handle(AnnotationValues<Jacksonized> annotation, JCAnnotation ast, JavacNode annotationNode) {
+		JavacNode annotatedNode = annotationNode.up();
+		deleteAnnotationIfNeccessary(annotationNode, Jacksonized.class);
+		
+		JavacNode tdNode;
+		if (annotatedNode.getKind() != Kind.TYPE)
+			tdNode = annotatedNode.up(); // @Jacksonized on a constructor or a static factory method.
+		else
+			tdNode = annotatedNode; // @Jacksonized on the class.
+		JCClassDecl td = (JCClassDecl) tdNode.get();
+
+		JavacNode builderAnnotationNode = findAnnotation(Builder.class, annotatedNode);
+		JavacNode superBuilderAnnotationNode = findAnnotation(SuperBuilder.class, annotatedNode);
+		if (builderAnnotationNode == null && superBuilderAnnotationNode == null) {
+			annotationNode.addWarning("@Jacksonized requires @Builder or @SuperBuilder for it to mean anything.");
+			return;
+		}
+
+		if (builderAnnotationNode != null && superBuilderAnnotationNode != null) {
+			annotationNode.addError("@Jacksonized cannot process both @Builder and @SuperBuilder on the same class.");
+			return;
+		}
+
+		boolean isAbstract = (td.mods.flags & Flags.ABSTRACT) != 0;
+		if (isAbstract) {
+			annotationNode.addError("Builders on abstract classes cannot be @Jacksonized (the builder would never be used).");
+			return;
+		}
+		
+		AnnotationValues<Builder> builderAnnotation = builderAnnotationNode != null ? 
+			createAnnotation(Builder.class, builderAnnotationNode) :
+				null;
+		AnnotationValues<SuperBuilder> superBuilderAnnotation = superBuilderAnnotationNode != null ? 
+			createAnnotation(SuperBuilder.class, superBuilderAnnotationNode) :
+				null;
+		
+		String setPrefix = builderAnnotation != null ? 
+			builderAnnotation.getInstance().setterPrefix() :
+				superBuilderAnnotation.getInstance().setterPrefix();
+		String buildMethodName = builderAnnotation != null ? 
+			builderAnnotation.getInstance().buildMethodName() :
+				superBuilderAnnotation.getInstance().buildMethodName();
+		
+		JavacTreeMaker maker = annotatedNode.getTreeMaker();
+
+		// Now lets find the generated builder class.
+		String builderClassName = getBuilderClassName(ast, annotationNode, annotatedNode, td, builderAnnotation, maker);
+
+		JCClassDecl builderClass = null;
+		for (JCTree member : td.getMembers()) {
+			if (member instanceof JCClassDecl && ((JCClassDecl) member).getSimpleName().contentEquals(builderClassName)) {
+				builderClass = (JCClassDecl) member;
+				break;
+			}
+		}
+		
+		if (builderClass == null) {
+			annotationNode.addError("Could not find @(Super)Builder's generated builder class for @Jacksonized processing. If there are other compiler errors, fix them first.");
+			return;
+		}
+		
+		// Insert @JsonDeserialize on annotated class.
+		if (hasAnnotation("com.fasterxml.jackson.databind.annotation.JsonDeserialize", tdNode)) {
+			annotationNode.addError("@JsonDeserialize already exists on class. Either delete @JsonDeserialize, or remove @Jacksonized and manually configure Jackson.");
+			return;
+		}
+		JCExpression jsonDeserializeType = chainDots(annotatedNode, "com", "fasterxml", "jackson", "databind", "annotation", "JsonDeserialize");
+		JCExpression builderClassExpression = namePlusTypeParamsToTypeReference(maker, tdNode, annotationNode.toName(builderClassName), false, List.<JCTypeParameter>nil());
+		JCFieldAccess builderClassReference = maker.Select(builderClassExpression, annotatedNode.toName("class"));
+		JCExpression assign = maker.Assign(maker.Ident(annotationNode.toName("builder")), builderClassReference);
+		JCAnnotation annotationJsonDeserialize = maker.Annotation(jsonDeserializeType, List.of(assign));
+		td.mods.annotations = td.mods.annotations.append(annotationJsonDeserialize);
+		
+		// Copy annotations from the class to the builder class.
+		List<JCAnnotation> copyableAnnotations = findJacksonAnnotationsOnClass(tdNode);
+		List<JCAnnotation> copiedAnnotations = copyAnnotations(copyableAnnotations);
+		builderClass.mods.annotations = builderClass.mods.annotations.appendList(copiedAnnotations);
+		
+		// Insert @JsonPOJOBuilder on the builder class.
+		JCExpression jsonPOJOBuilderType = chainDots(annotatedNode, "com", "fasterxml", "jackson", "databind", "annotation", "JsonPOJOBuilder");
+		JCExpression withPrefixExpr = maker.Assign(maker.Ident(annotationNode.toName("withPrefix")), maker.Literal(setPrefix));
+		JCExpression buildMethodNameExpr = maker.Assign(maker.Ident(annotationNode.toName("buildMethodName")), maker.Literal(buildMethodName));
+		JCAnnotation annotationJsonPOJOBuilder = maker.Annotation(jsonPOJOBuilderType, List.of(withPrefixExpr, buildMethodNameExpr));
+		builderClass.mods.annotations = builderClass.mods.annotations.append(annotationJsonPOJOBuilder);
+
+		// @SuperBuilder? Make it package-private!
+		if (superBuilderAnnotationNode != null)
+			builderClass.mods.flags = builderClass.mods.flags & ~Flags.PRIVATE;
+		
+ 	}
+
+	private String getBuilderClassName(JCAnnotation ast, JavacNode annotationNode, JavacNode annotatedNode, JCClassDecl td, AnnotationValues<Builder> builderAnnotation, JavacTreeMaker maker) {
+		String builderClassName = builderAnnotation != null ? 
+			builderAnnotation.getInstance().builderClassName() : null;
+		if (builderClassName == null || builderClassName.isEmpty()) {
+			builderClassName = annotationNode.getAst().readConfiguration(ConfigurationKeys.BUILDER_CLASS_NAME);
+			if (builderClassName == null || builderClassName.isEmpty())
+				builderClassName = "*Builder";
+
+			JCMethodDecl fillParametersFrom = annotatedNode.get() instanceof JCMethodDecl ? (JCMethodDecl)annotatedNode.get() : null;
+			String replacement;
+			if (fillParametersFrom != null && !fillParametersFrom.getName().toString().equals("<init>")) {
+				// @Builder on a method: Use name of return type for builder class name.
+				JCExpression returnType = fillParametersFrom.restype;
+				List<JCTypeParameter> typeParams = fillParametersFrom.typarams;
+				if (returnType instanceof JCTypeApply) {
+					returnType = cloneType(maker, returnType, ast, annotationNode.getContext());
+				}
+				replacement = HandleBuilder.returnTypeToBuilderClassName(annotationNode, td, returnType, typeParams);
+			} else {
+				// @Builder on class or constructor: Use the class name.
+				replacement = td.name.toString();
+			}
+			builderClassName = builderClassName.replace("*", replacement);
+		}
+
+		if (builderAnnotation == null)
+			builderClassName += "Impl"; // For @SuperBuilder, all Jackson annotations must be put on the BuilderImpl class.
+		
+		return builderClassName;
+	}
+	
+	private static List<JCAnnotation> findJacksonAnnotationsOnClass(JavacNode node) {
+		ListBuffer<JCAnnotation> result = new ListBuffer<JCAnnotation>();
+		for (JavacNode child : node.down()) {
+			if (child.getKind() == Kind.ANNOTATION) {
+				JCAnnotation annotation = (JCAnnotation) child.get();
+				for (String bn : HandlerUtil.JACKSON_COPY_TO_BUILDER_ANNOTATIONS) { 
+					if (typeMatches(bn, node, annotation.annotationType)) {
+						result.append(annotation);
+						break;
+					}
+				}
+			}
+		}
+		return result.toList();
+	}
+}