Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.apache.drill.exec.compile; import java.util.HashMap; import org.objectweb.asm.AnnotationVisitor; import org.objectweb.asm.Attribute; import org.objectweb.asm.Handle; import org.objectweb.asm.Label; import org.objectweb.asm.MethodVisitor; import org.objectweb.asm.TypePath; /** * A MethodVisitor that verifies the required call sequence according to * http://asm.ow2.org/asm50/javadoc/user/org/objectweb/asm/MethodVisitor.html . * * <p> * There is no CheckAnnotationVisitorFsm at this time. */ public class CheckMethodVisitorFsm extends MethodVisitor { /* * From * http://asm.ow2.org/asm50/javadoc/user/org/objectweb/asm/MethodVisitor.html: * "The methods of this class must be called in the following order: ( * visitParameter )* [ visitAnnotationDefault ] ( visitAnnotation | * visitTypeAnnotation | visitAttribute )* [ visitCode ( visitFrame | * visitXInsn | visitLabel | visitInsnAnnotation | visitTryCatchBlock | * visitTryCatchBlockAnnotation | visitLocalVariable | * visitLocalVariableAnnotation | visitLineNumber )* visitMaxs ] visitEnd. */ private final static FsmDescriptor fsmDescriptor = createFsmDescriptor(); private static FsmDescriptor createFsmDescriptor() { final HashMap<String, Character> tokenMap = new HashMap<>(); tokenMap.put("visitParameter", 'P'); tokenMap.put("visitAnnotationDefault", 'D'); tokenMap.put("visitAnnotation", 'A'); tokenMap.put("visitTypeAnnotation", 'T'); tokenMap.put("visitAttribute", 'R'); tokenMap.put("visitCode", 'C'); tokenMap.put("visitFrame", 'F'); tokenMap.put("visitXInsn", 'X'); // represents all Insn calls tokenMap.put("visitLabel", 'L'); tokenMap.put("visitInsnAnnotation", 'I'); tokenMap.put("visitTryCatchBlock", 'B'); tokenMap.put("visitTryCatchBlockAnnotation", 'E'); // "Exception" tokenMap.put("visitLocalVariable", 'V'); tokenMap.put("visitLocalVariableAnnotation", 'N'); // "Note" tokenMap.put("visitLineNumber", '#'); tokenMap.put("visitMaxs", 'M'); tokenMap.put("visitEnd", 'e'); return new FsmDescriptor(tokenMap, "P*+D?+(A|T|R)*+(C(F|X|L|I|B|E|V|N|\\#)*+M)?+e", "visitEnd"); } private final FsmCursor fsmCursor; /** * See {@link org.objectweb.asm.MethodVisitor#MethodVisitor(int, MethodVisitor)}. */ public CheckMethodVisitorFsm(final int api, final MethodVisitor mv) { super(api, mv); fsmCursor = fsmDescriptor.createCursor(); } @Override public AnnotationVisitor visitAnnotation(final String desc, final boolean visible) { fsmCursor.transition("visitAnnotation"); final AnnotationVisitor annotationVisitor = super.visitAnnotation(desc, visible); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public AnnotationVisitor visitAnnotationDefault() { fsmCursor.transition("visitAnnotationDefault"); final AnnotationVisitor annotationVisitor = super.visitAnnotationDefault(); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public void visitAttribute(final Attribute attr) { fsmCursor.transition("visitAttribute"); super.visitAttribute(attr); } @Override public void visitCode() { fsmCursor.transition("visitCode"); super.visitCode(); } @Override public void visitEnd() { fsmCursor.transition("visitEnd"); super.visitEnd(); } @Override public void visitFieldInsn(final int opcode, final String owner, final String name, final String desc) { fsmCursor.transition("visitXInsn"); super.visitFieldInsn(opcode, owner, name, desc); } @Override public void visitFrame(final int type, final int nLocal, final Object[] local, final int nStack, final Object[] stack) { fsmCursor.transition("visitFrame"); super.visitFrame(type, nLocal, local, nStack, stack); } @Override public void visitIincInsn(final int var, final int increment) { fsmCursor.transition("visitXInsn"); super.visitIincInsn(var, increment); } @Override public void visitInsn(final int opcode) { fsmCursor.transition("visitXInsn"); super.visitInsn(opcode); } @Override public AnnotationVisitor visitInsnAnnotation(final int typeRef, final TypePath typePath, final String desc, final boolean visible) { fsmCursor.transition("visitInsnAnnotation"); final AnnotationVisitor annotationVisitor = super.visitInsnAnnotation(typeRef, typePath, desc, visible); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public void visitIntInsn(final int opcode, final int operand) { fsmCursor.transition("visitXInsn"); super.visitIntInsn(opcode, operand); } @Override public void visitInvokeDynamicInsn(final String name, final String desc, final Handle bsm, final Object... bsmArgs) { fsmCursor.transition("visitXInsn"); super.visitInvokeDynamicInsn(name, desc, bsm, bsmArgs); } @Override public void visitJumpInsn(final int opcode, final Label label) { fsmCursor.transition("visitXInsn"); super.visitJumpInsn(opcode, label); } @Override public void visitLabel(final Label label) { fsmCursor.transition("visitLabel"); super.visitLabel(label); } @Override public void visitLdcInsn(final Object cst) { fsmCursor.transition("visitXInsn"); super.visitLdcInsn(cst); } @Override public void visitLineNumber(final int line, final Label start) { fsmCursor.transition("visitLineNumber"); super.visitLineNumber(line, start); } @Override public void visitLocalVariable(final String name, final String desc, final String signature, final Label start, final Label end, final int index) { fsmCursor.transition("visitLocalVariable"); super.visitLocalVariable(name, desc, signature, start, end, index); } @Override public AnnotationVisitor visitLocalVariableAnnotation(final int typeRef, final TypePath typePath, final Label[] start, final Label[] end, final int[] index, final String desc, final boolean visible) { fsmCursor.transition("visitLocalVariableAnnotation"); final AnnotationVisitor annotationVisitor = super.visitLocalVariableAnnotation(typeRef, typePath, start, end, index, desc, visible); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public void visitLookupSwitchInsn(final Label dflt, final int[] keys, final Label[] labels) { fsmCursor.transition("visitXInsn"); super.visitLookupSwitchInsn(dflt, keys, labels); } @Override public void visitMaxs(final int maxStack, final int maxLocals) { fsmCursor.transition("visitMaxs"); super.visitMaxs(maxStack, maxLocals); } @Deprecated @Override public void visitMethodInsn(final int opcode, final String owner, final String name, final String desc) { fsmCursor.transition("visitXInsn"); super.visitMethodInsn(opcode, owner, name, desc); } @Override public void visitMethodInsn(final int opcode, final String owner, final String name, final String desc, final boolean itf) { fsmCursor.transition("visitXInsn"); super.visitMethodInsn(opcode, owner, name, desc, itf); } @Override public void visitMultiANewArrayInsn(final String desc, final int dims) { fsmCursor.transition("visitXInsn"); super.visitMultiANewArrayInsn(desc, dims); } @Override public void visitParameter(final String name, final int access) { fsmCursor.transition("visitParameter"); super.visitParameter(name, access); } @Override public AnnotationVisitor visitParameterAnnotation(final int parameter, final String desc, final boolean visible) { fsmCursor.transition("visitParameterAnnotation"); final AnnotationVisitor annotationVisitor = super.visitParameterAnnotation(parameter, desc, visible); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public void visitTableSwitchInsn(final int min, final int max, final Label dflt, final Label... labels) { fsmCursor.transition("visitXInsn"); super.visitTableSwitchInsn(min, max, dflt, labels); } @Override public AnnotationVisitor visitTryCatchAnnotation(final int typeRef, final TypePath typePath, final String desc, final boolean visible) { fsmCursor.transition("visitTryCatchAnnotation"); final AnnotationVisitor annotationVisitor = super.visitTryCatchAnnotation(typeRef, typePath, desc, visible); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public void visitTryCatchBlock(final Label start, final Label end, final Label handler, final String type) { fsmCursor.transition("visitTryCatchBlock"); super.visitTryCatchBlock(start, end, handler, type); } @Override public AnnotationVisitor visitTypeAnnotation(final int typeRef, final TypePath typePath, final String desc, final boolean visible) { fsmCursor.transition("visitTypeAnnotation"); final AnnotationVisitor annotationVisitor = super.visitTypeAnnotation(typeRef, typePath, desc, visible); return annotationVisitor; // TODO: add CheckAnnotationVisitorFsm } @Override public void visitTypeInsn(final int opcode, final String type) { fsmCursor.transition("visitXInsn"); super.visitTypeInsn(opcode, type); } @Override public void visitVarInsn(final int opcode, final int var) { fsmCursor.transition("visitXInsn"); super.visitVarInsn(opcode, var); } }