Java tutorial
/* * Copyright 2000-2009 JetBrains s.r.o. * * Licensed 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 com.intellij.compiler.notNullVerification; import org.objectweb.asm.*; import java.util.ArrayList; /** * @author ven * @noinspection HardCodedStringLiteral * * Note: this is copy of {@link NotNullVerifyingInstrumenter} which supported JSR 305 annotation */ public class NonnullVerifyingInstrumenter extends ClassAdapter implements Opcodes { private boolean myIsModification = false; private String myClassName; public static final String NOT_NULL = "javax/annotation/Nonnull"; public static final String NOT_NULL_ANNO = "L" + NOT_NULL + ";"; public static final String IAE_CLASS_NAME = "java/lang/IllegalArgumentException"; public static final String ISE_CLASS_NAME = "java/lang/IllegalStateException"; private static final String CONSTRUCTOR_NAME = "<init>"; public NonnullVerifyingInstrumenter(final ClassVisitor classVisitor) { super(classVisitor); } public boolean isModification() { return myIsModification; } public void visit(final int version, final int access, final String name, final String signature, final String superName, final String[] interfaces) { super.visit(version, access, name, signature, superName, interfaces); myClassName = name; } public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature, final String[] exceptions) { final Type[] args = Type.getArgumentTypes(desc); final Type returnType = Type.getReturnType(desc); MethodVisitor v = cv.visitMethod(access, name, desc, signature, exceptions); return new MethodAdapter(v) { private final ArrayList myNotNullParams = new ArrayList(); private int mySyntheticCount = 0; private boolean myIsNotNull = false; //private boolean myIsUnmodifiable = false; public Label myThrowLabel; //public Label myWrapLabel; private Label myStartGeneratedCodeLabel; public AnnotationVisitor visitParameterAnnotation(final int parameter, final String anno, final boolean visible) { AnnotationVisitor av; av = mv.visitParameterAnnotation(parameter, anno, visible); if (isReferenceType(args[parameter]) && anno.equals(NOT_NULL_ANNO)) { myNotNullParams.add(new Integer(parameter)); } else if (anno.equals("Ljava/lang/Synthetic;")) { // See asm r1278 for what we do this, // http://forge.objectweb.org/tracker/index.php?func=detail&aid=307392&group_id=23&atid=100023 mySyntheticCount++; } return av; } public AnnotationVisitor visitAnnotation(String anno, boolean isRuntime) { final AnnotationVisitor av = mv.visitAnnotation(anno, isRuntime); if (isReferenceType(returnType) && anno.equals(NOT_NULL_ANNO)) { myIsNotNull = true; } return av; } public void visitCode() { if (myNotNullParams.size() > 0) { myStartGeneratedCodeLabel = new Label(); mv.visitLabel(myStartGeneratedCodeLabel); } for (int p = 0; p < myNotNullParams.size(); ++p) { int var = ((access & ACC_STATIC) == 0) ? 1 : 0; int param = ((Integer) myNotNullParams.get(p)).intValue(); for (int i = 0; i < param; ++i) { var += args[i].getSize(); } mv.visitVarInsn(ALOAD, var); Label end = new Label(); mv.visitJumpInsn(IFNONNULL, end); generateThrow(IAE_CLASS_NAME, "Argument " + (param - mySyntheticCount) + " for @NotNull parameter of " + myClassName + "." + name + " must not be null", end); } } public void visitLocalVariable(final String name, final String desc, final String signature, final Label start, final Label end, final int index) { final boolean isStatic = (access & ACC_STATIC) != 0; final boolean isParameter = isStatic ? index < args.length : index <= args.length; mv.visitLocalVariable(name, desc, signature, (isParameter && myStartGeneratedCodeLabel != null) ? myStartGeneratedCodeLabel : start, end, index); } public void visitInsn(int opcode) { if (opcode == ARETURN) { if (myIsNotNull) { mv.visitInsn(DUP); /*generateConditionalThrow("@NotNull method " + myClassName + "." + name + " must not return null", "java/lang/IllegalStateException");*/ if (myThrowLabel == null) { Label skipLabel = new Label(); mv.visitJumpInsn(IFNONNULL, skipLabel); myThrowLabel = new Label(); mv.visitLabel(myThrowLabel); generateThrow(ISE_CLASS_NAME, "@NotNull method " + myClassName + "." + name + " must not return null", skipLabel); } else { mv.visitJumpInsn(IFNULL, myThrowLabel); } } } mv.visitInsn(opcode); } private void generateThrow(final String exceptionClass, final String descr, final Label end) { String exceptionParamClass = "(Ljava/lang/String;)V"; mv.visitTypeInsn(NEW, exceptionClass); mv.visitInsn(DUP); mv.visitLdcInsn(descr); mv.visitMethodInsn(INVOKESPECIAL, exceptionClass, CONSTRUCTOR_NAME, exceptionParamClass); mv.visitInsn(ATHROW); mv.visitLabel(end); myIsModification = true; } public void visitMaxs(final int maxStack, final int maxLocals) { try { super.visitMaxs(maxStack, maxLocals); } catch (ArrayIndexOutOfBoundsException e) { throw new ArrayIndexOutOfBoundsException( "maxs processing failed for method " + name + ": " + e.getMessage()); } } }; } private static boolean isReferenceType(final Type type) { return type.getSort() == Type.OBJECT || type.getSort() == Type.ARRAY; } }