1 files changed, 69 insertions, 0 deletions
diff --git a/src/lombok/javac/handlers/HandleSynchronized.java b/src/lombok/javac/handlers/HandleSynchronized.java
new file mode 100644
index 00000000..4acb6e27
--- /dev/null
+++ b/src/lombok/javac/handlers/HandleSynchronized.java
@@ -0,0 +1,69 @@
+package lombok.javac.handlers;
+
+import static lombok.javac.handlers.PKG.*;
+
+import org.mangosdk.spi.ProviderFor;
+
+import com.sun.tools.javac.code.Flags;
+import com.sun.tools.javac.code.TypeTags;
+import com.sun.tools.javac.tree.TreeMaker;
+import com.sun.tools.javac.tree.JCTree.JCAnnotation;
+import com.sun.tools.javac.tree.JCTree.JCExpression;
+import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
+import com.sun.tools.javac.tree.JCTree.JCNewArray;
+import com.sun.tools.javac.tree.JCTree.JCStatement;
+import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
+import com.sun.tools.javac.util.List;
+
+import lombok.Synchronized;
+import lombok.core.AnnotationValues;
+import lombok.core.AST.Kind;
+import lombok.javac.JavacAnnotationHandler;
+import lombok.javac.JavacAST.Node;
+
+@ProviderFor(JavacAnnotationHandler.class)
+public class HandleSynchronized implements JavacAnnotationHandler<Synchronized> {
+	private static final String INSTANCE_LOCK_NAME = "$lock";
+	private static final String STATIC_LOCK_NAME = "$LOCK";
+	
+	@Override public boolean handle(AnnotationValues<Synchronized> annotation, JCAnnotation ast, Node annotationNode) {
+		Node methodNode = annotationNode.up();
+		
+		if ( methodNode == null || methodNode.getKind() != Kind.METHOD || !(methodNode.get() instanceof JCMethodDecl) ) {
+			annotationNode.addError("@Synchronized is legal only on methods.");
+			return true;
+		}
+		
+		JCMethodDecl method = (JCMethodDecl)methodNode.get();
+		
+		if ( (method.mods.flags & Flags.ABSTRACT) != 0 ) {
+			annotationNode.addError("@Synchronized is legal only on concrete methods.");
+			return true;
+		}
+		boolean isStatic = (method.mods.flags & Flags.STATIC) != 0;
+		String lockName = isStatic ? STATIC_LOCK_NAME : INSTANCE_LOCK_NAME;
+		
+		TreeMaker maker = methodNode.getTreeMaker();
+		
+		if ( fieldExists(lockName, methodNode) == MemberExistsResult.NOT_EXISTS ) {
+			JCExpression objectType = chainDots(maker, methodNode, "java", "lang", "Object");
+			//We use 'new Object[0];' because quite unlike 'new Object();', empty arrays *ARE* serializable!
+			JCNewArray newObjectArray = maker.NewArray(chainDots(maker, methodNode, "java", "lang", "Object"),
+					List.<JCExpression>of(maker.Literal(TypeTags.INT, 0)), null);
+			JCVariableDecl fieldDecl = maker.VarDef(
+					maker.Modifiers(Flags.FINAL | (isStatic ? Flags.STATIC : 0)),
+					methodNode.toName(lockName), objectType, newObjectArray);
+			injectField(methodNode.up(), fieldDecl);
+		}
+		
+		if ( method.body == null ) return false;
+		
+		JCExpression lockNode = maker.Ident(methodNode.toName(lockName));
+		
+		method.body = maker.Block(0, List.<JCStatement>of(maker.Synchronized(lockNode, method.body)));
+		
+		methodNode.rebuild();
+		
+		return true;
+	}
+}