diff options
Diffstat (limited to 'src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java')
-rw-r--r-- | src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java b/src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java new file mode 100644 index 00000000..1402138b --- /dev/null +++ b/src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java @@ -0,0 +1,100 @@ +/* + * Copyright © 2009 Reinier Zwitserloot and Roel Spilker. + * + * 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.eclipse.agent; + +import org.objectweb.asm.ClassAdapter; +import org.objectweb.asm.ClassReader; +import org.objectweb.asm.ClassVisitor; +import org.objectweb.asm.ClassWriter; +import org.objectweb.asm.MethodAdapter; +import org.objectweb.asm.MethodVisitor; +import org.objectweb.asm.Opcodes; + +/** + * Transforms Eclipse's <code>org.eclipse.jdt.core.dom.ASTConverter</code> class, which sometimes rescans bits and pieces + * of source files because Eclipse's own AST doesn't actually have enough information for eclipse (why they don't just fix + * the AST tree generator is beyond me). At any rate, for catch blocks generated by lombok, eclipse tries to rescan the + * source file to find the source position of the catch statement, which will of course fail as there's nothing there. + * We will fix the code to return the original starting position, which is a pretty good simile, instead of '-1', which + * screws up all sorts of things. + * + * Transformations applied:<ul> + * <li>The <code>retrieveStartingCatchPosition(int, int)</code> method is instrumented to return its first parameter + * instead of the constant -1.</li></ul> + */ +class EclipseASTConverterTransformer { + byte[] transform(byte[] classfileBuffer) { + ClassReader reader = new ClassReader(classfileBuffer); + ClassWriter writer = new ClassWriter(reader, 0); + + ClassAdapter adapter = new ASTConverterPatcherAdapter(writer); + reader.accept(adapter, 0); + return writer.toByteArray(); + } + + static RuntimeException sneakyThrow(Throwable t) { + if ( t == null ) throw new NullPointerException("t"); + EclipseASTConverterTransformer.<RuntimeException>sneakyThrow0(t); + return null; + } + + @SuppressWarnings("unchecked") + private static <T extends Throwable> void sneakyThrow0(Throwable t) throws T { + throw (T)t; + } + + private static class ASTConverterPatcherAdapter extends ClassAdapter { + public ASTConverterPatcherAdapter(ClassVisitor cv) { + super(cv); + } + + @Override public MethodVisitor visitMethod(int access, String name, String desc, + String signature, String[] exceptions) { + MethodVisitor writerVisitor = super.visitMethod(access, name, desc, signature, exceptions); + if ( !name.equals("retrieveStartingCatchPosition") ) return writerVisitor; + + return new RetrieveStartingCatchPositionPatcher(writerVisitor); + } + } + + static class RetrieveStartingCatchPositionPatcher extends MethodAdapter { + RetrieveStartingCatchPositionPatcher(MethodVisitor mv) { + super(mv); + } + + int count = 0; + @Override public void visitInsn(int opcode) { + if ( opcode == Opcodes.IRETURN ) { + if ( count++ == 0 ) { + super.visitInsn(opcode); + return; + } + //replaces: "return -1" with "return [firstParam]"; + super.visitInsn(Opcodes.POP); + super.visitVarInsn(Opcodes.ILOAD, 1); + super.visitInsn(Opcodes.IRETURN); + } else { + super.visitInsn(opcode); + } + } + } +} |