Java tutorial
/* * Copyright (C) 2010-2014 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.bytecode; import static lombok.bytecode.AsmUtil.*; import java.util.concurrent.atomic.AtomicBoolean; import lombok.core.DiagnosticsReceiver; import lombok.core.PostCompilerTransformation; import org.mangosdk.spi.ProviderFor; import org.objectweb.asm.ClassReader; import org.objectweb.asm.ClassVisitor; import org.objectweb.asm.ClassWriter; import org.objectweb.asm.Handle; import org.objectweb.asm.Label; import org.objectweb.asm.MethodVisitor; import org.objectweb.asm.Opcodes; @ProviderFor(PostCompilerTransformation.class) public class SneakyThrowsRemover implements PostCompilerTransformation { @Override public byte[] applyTransformations(byte[] original, String fileName, final DiagnosticsReceiver diagnostics) { if (!new ClassFileMetaData(original).usesMethod("lombok/Lombok", "sneakyThrow")) return null; byte[] fixedByteCode = fixJSRInlining(original); ClassReader reader = new ClassReader(fixedByteCode); ClassWriter writer = new ClassWriter(reader, 0); final AtomicBoolean changesMade = new AtomicBoolean(); class SneakyThrowsRemoverVisitor extends MethodVisitor { SneakyThrowsRemoverVisitor(MethodVisitor mv) { super(Opcodes.ASM5, mv); } private boolean methodInsnQueued = false; @Override public void visitMethodInsn(int opcode, String owner, String name, String desc, boolean itf) { if (opcode == Opcodes.INVOKESTATIC && "sneakyThrow".equals(name) && "lombok/Lombok".equals(owner) && "(Ljava/lang/Throwable;)Ljava/lang/RuntimeException;".equals(desc)) { if (System.getProperty("lombok.debugAsmOnly", null) != null) { super.visitMethodInsn(opcode, owner, name, desc, itf); // DEBUG for issue 470! } else { methodInsnQueued = true; } } else { super.visitMethodInsn(opcode, owner, name, desc, itf); } } private void handleQueue() { if (!methodInsnQueued) return; super.visitMethodInsn(Opcodes.INVOKESTATIC, "lombok/Lombok", "sneakyThrow", "(Ljava/lang/Throwable;)Ljava/lang/RuntimeException;", false); methodInsnQueued = false; diagnostics.addWarning( "Proper usage is: throw lombok.Lombok.sneakyThrow(someException);. You did not 'throw' it. Because of this, the call to sneakyThrow " + "remains in your classfile and you will need lombok.jar on the classpath at runtime."); } @Override public void visitInsn(int arg0) { if (methodInsnQueued && arg0 == Opcodes.ATHROW) { changesMade.set(true); // As expected, the required ATHROW. We can now safely 'eat' the previous call. methodInsnQueued = false; } handleQueue(); super.visitInsn(arg0); } @Override public void visitFrame(int arg0, int arg1, Object[] arg2, int arg3, Object[] arg4) { handleQueue(); super.visitFrame(arg0, arg1, arg2, arg3, arg4); } @Override public void visitIincInsn(int arg0, int arg1) { handleQueue(); super.visitIincInsn(arg0, arg1); } @Override public void visitFieldInsn(int arg0, String arg1, String arg2, String arg3) { handleQueue(); super.visitFieldInsn(arg0, arg1, arg2, arg3); } @Override public void visitIntInsn(int arg0, int arg1) { handleQueue(); super.visitIntInsn(arg0, arg1); } @Override public void visitEnd() { handleQueue(); super.visitEnd(); } @Override public void visitInvokeDynamicInsn(String arg0, String arg1, Handle arg2, Object... arg3) { handleQueue(); super.visitInvokeDynamicInsn(arg0, arg1, arg2, arg3); } @Override public void visitLabel(Label arg0) { handleQueue(); super.visitLabel(arg0); } @Override public void visitJumpInsn(int arg0, Label arg1) { handleQueue(); super.visitJumpInsn(arg0, arg1); } @Override public void visitLdcInsn(Object arg0) { handleQueue(); super.visitLdcInsn(arg0); } @Override public void visitLocalVariable(String arg0, String arg1, String arg2, Label arg3, Label arg4, int arg5) { handleQueue(); super.visitLocalVariable(arg0, arg1, arg2, arg3, arg4, arg5); } @Override public void visitMaxs(int arg0, int arg1) { handleQueue(); super.visitMaxs(arg0, arg1); } @Override public void visitLookupSwitchInsn(Label arg0, int[] arg1, Label[] arg2) { handleQueue(); super.visitLookupSwitchInsn(arg0, arg1, arg2); } @Override public void visitMultiANewArrayInsn(String arg0, int arg1) { handleQueue(); super.visitMultiANewArrayInsn(arg0, arg1); } @Override public void visitVarInsn(int arg0, int arg1) { handleQueue(); super.visitVarInsn(arg0, arg1); } @Override public void visitTryCatchBlock(Label arg0, Label arg1, Label arg2, String arg3) { handleQueue(); super.visitTryCatchBlock(arg0, arg1, arg2, arg3); } @Override public void visitTableSwitchInsn(int arg0, int arg1, Label arg2, Label... arg3) { handleQueue(); super.visitTableSwitchInsn(arg0, arg1, arg2, arg3); } @Override public void visitTypeInsn(int arg0, String arg1) { handleQueue(); super.visitTypeInsn(arg0, arg1); } } reader.accept(new ClassVisitor(Opcodes.ASM5, writer) { @Override public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) { return new SneakyThrowsRemoverVisitor(super.visitMethod(access, name, desc, signature, exceptions)); } }, 0); return changesMade.get() ? writer.toByteArray() : null; } }