checkmethodadapter.java

asm的源码包 并且包含英文的文档

/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2005 INRIA, France Telecom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.objectweb.asm.util;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodAdapter;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Attribute;
import org.objectweb.asm.Type;

import java.util.HashMap;

/**
 * A {@link MethodAdapter} that checks that its methods are properly used. More
 * precisely this code adapter checks each instruction individually (i.e., each
 * visit method checks some preconditions based <i>only</i> on its arguments -
 * such as the fact that the given opcode is correct for a given visit method),
 * but does <i>not</i> check the <i>sequence</i> of instructions. For example,
 * in a method whose signature is <tt>void m ()</tt>, the invalid instruction
 * IRETURN, or the invalid sequence IADD L2I will <i>not</i> be detected by
 * this code adapter.
 * 
 * @author Eric Bruneton
 */
public class CheckMethodAdapter extends MethodAdapter {

    /**
     * <tt>true</tt> if the visitCode method has been called.
     */
    private boolean startCode;

    /**
     * <tt>true</tt> if the visitMaxs method has been called.
     */
    private boolean endCode;

    /**
     * <tt>true</tt> if the visitEnd method has been called.
     */
    private boolean endMethod;

    /**
     * The already visited labels. This map associate Integer values to Label
     * keys.
     */
    private HashMap labels;

    /**
     * Code of the visit method to be used for each opcode.
     */
    private final static int[] TYPE;

    static {
        String s = "BBBBBBBBBBBBBBBBCCIAADDDDDAAAAAAAAAAAAAAAAAAAABBBBBBBBDD"
                + "DDDAAAAAAAAAAAAAAAAAAAABBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB"
                + "BBBBBBBBBBBBBBBBBBBJBBBBBBBBBBBBBBBBBBBBHHHHHHHHHHHHHHHHD"
                + "KLBBBBBBFFFFGGGGAECEBBEEBBAMHHAA";
        TYPE = new int[s.length()];
        for (int i = 0; i < TYPE.length; ++i) {
            TYPE[i] = s.charAt(i) - 'A' - 1;
        }
    }

    // code to generate the above string
    // public static void main (String[] args) {
    // int[] TYPE = new int[] {
    // 0, //NOP
    // 0, //ACONST_NULL
    // 0, //ICONST_M1
    // 0, //ICONST_0
    // 0, //ICONST_1
    // 0, //ICONST_2
    // 0, //ICONST_3
    // 0, //ICONST_4
    // 0, //ICONST_5
    // 0, //LCONST_0
    // 0, //LCONST_1
    // 0, //FCONST_0
    // 0, //FCONST_1
    // 0, //FCONST_2
    // 0, //DCONST_0
    // 0, //DCONST_1
    // 1, //BIPUSH
    // 1, //SIPUSH
    // 7, //LDC
    // -1, //LDC_W
    // -1, //LDC2_W
    // 2, //ILOAD
    // 2, //LLOAD
    // 2, //FLOAD
    // 2, //DLOAD
    // 2, //ALOAD
    // -1, //ILOAD_0
    // -1, //ILOAD_1
    // -1, //ILOAD_2
    // -1, //ILOAD_3
    // -1, //LLOAD_0
    // -1, //LLOAD_1
    // -1, //LLOAD_2
    // -1, //LLOAD_3
    // -1, //FLOAD_0
    // -1, //FLOAD_1
    // -1, //FLOAD_2
    // -1, //FLOAD_3
    // -1, //DLOAD_0
    // -1, //DLOAD_1
    // -1, //DLOAD_2
    // -1, //DLOAD_3
    // -1, //ALOAD_0
    // -1, //ALOAD_1
    // -1, //ALOAD_2
    // -1, //ALOAD_3
    // 0, //IALOAD
    // 0, //LALOAD
    // 0, //FALOAD
    // 0, //DALOAD
    // 0, //AALOAD
    // 0, //BALOAD
    // 0, //CALOAD
    // 0, //SALOAD
    // 2, //ISTORE
    // 2, //LSTORE
    // 2, //FSTORE
    // 2, //DSTORE
    // 2, //ASTORE
    // -1, //ISTORE_0
    // -1, //ISTORE_1
    // -1, //ISTORE_2
    // -1, //ISTORE_3
    // -1, //LSTORE_0
    // -1, //LSTORE_1
    // -1, //LSTORE_2
    // -1, //LSTORE_3
    // -1, //FSTORE_0
    // -1, //FSTORE_1
    // -1, //FSTORE_2
    // -1, //FSTORE_3
    // -1, //DSTORE_0
    // -1, //DSTORE_1
    // -1, //DSTORE_2
    // -1, //DSTORE_3
    // -1, //ASTORE_0
    // -1, //ASTORE_1
    // -1, //ASTORE_2
    // -1, //ASTORE_3
    // 0, //IASTORE
    // 0, //LASTORE
    // 0, //FASTORE
    // 0, //DASTORE
    // 0, //AASTORE
    // 0, //BASTORE
    // 0, //CASTORE
    // 0, //SASTORE
    // 0, //POP
    // 0, //POP2
    // 0, //DUP
    // 0, //DUP_X1
    // 0, //DUP_X2
    // 0, //DUP2
    // 0, //DUP2_X1
    // 0, //DUP2_X2
    // 0, //SWAP
    // 0, //IADD
    // 0, //LADD
    // 0, //FADD
    // 0, //DADD
    // 0, //ISUB
    // 0, //LSUB
    // 0, //FSUB
    // 0, //DSUB
    // 0, //IMUL
    // 0, //LMUL
    // 0, //FMUL
    // 0, //DMUL
    // 0, //IDIV
    // 0, //LDIV
    // 0, //FDIV
    // 0, //DDIV
    // 0, //IREM
    // 0, //LREM
    // 0, //FREM
    // 0, //DREM
    // 0, //INEG
    // 0, //LNEG
    // 0, //FNEG
    // 0, //DNEG
    // 0, //ISHL
    // 0, //LSHL
    // 0, //ISHR
    // 0, //LSHR
    // 0, //IUSHR
    // 0, //LUSHR
    // 0, //IAND
    // 0, //LAND
    // 0, //IOR
    // 0, //LOR
    // 0, //IXOR
    // 0, //LXOR
    // 8, //IINC
    // 0, //I2L
    // 0, //I2F
    // 0, //I2D
    // 0, //L2I
    // 0, //L2F
    // 0, //L2D
    // 0, //F2I
    // 0, //F2L
    // 0, //F2D
    // 0, //D2I
    // 0, //D2L
    // 0, //D2F
    // 0, //I2B
    // 0, //I2C
    // 0, //I2S
    // 0, //LCMP
    // 0, //FCMPL
    // 0, //FCMPG
    // 0, //DCMPL
    // 0, //DCMPG
    // 6, //IFEQ
    // 6, //IFNE
    // 6, //IFLT
    // 6, //IFGE
    // 6, //IFGT
    // 6, //IFLE
    // 6, //IF_ICMPEQ
    // 6, //IF_ICMPNE
    // 6, //IF_ICMPLT
    // 6, //IF_ICMPGE
    // 6, //IF_ICMPGT
    // 6, //IF_ICMPLE
    // 6, //IF_ACMPEQ
    // 6, //IF_ACMPNE
    // 6, //GOTO
    // 6, //JSR
    // 2, //RET
    // 9, //TABLESWITCH
    // 10, //LOOKUPSWITCH
    // 0, //IRETURN
    // 0, //LRETURN
    // 0, //FRETURN
    // 0, //DRETURN
    // 0, //ARETURN
    // 0, //RETURN
    // 4, //GETSTATIC
    // 4, //PUTSTATIC
    // 4, //GETFIELD
    // 4, //PUTFIELD
    // 5, //INVOKEVIRTUAL
    // 5, //INVOKESPECIAL
    // 5, //INVOKESTATIC
    // 5, //INVOKEINTERFACE
    // -1, //UNUSED
    // 3, //NEW
    // 1, //NEWARRAY
    // 3, //ANEWARRAY
    // 0, //ARRAYLENGTH
    // 0, //ATHROW
    // 3, //CHECKCAST
    // 3, //INSTANCEOF
    // 0, //MONITORENTER
    // 0, //MONITOREXIT
    // -1, //WIDE
    // 11, //MULTIANEWARRAY
    // 6, //IFNULL
    // 6, //IFNONNULL
    // -1, //GOTO_W
    // -1 //JSR_W
    // };
    // for (int i = 0; i < TYPE.length; ++i) {
    // System.out.print((char)(TYPE[i] + 1 + 'A'));
    // }
    // System.out.println();
    // }

    /**
     * Constructs a new {@link CheckMethodAdapter} object.
     * 
     * @param cv the code visitor to which this adapter must delegate calls.
     */
    public CheckMethodAdapter(final MethodVisitor cv) {
        super(cv);
        this.labels = new HashMap();
    }

    public AnnotationVisitor visitAnnotation(
        final String desc,
        final boolean visible)
    {
        checkEndMethod();
        checkDesc(desc, false);
        return new CheckAnnotationAdapter(mv.visitAnnotation(desc, visible));
    }

    public AnnotationVisitor visitAnnotationDefault() {
        checkEndMethod();
        return new CheckAnnotationAdapter(mv.visitAnnotationDefault(), false);
    }

    public AnnotationVisitor visitParameterAnnotation(
        final int parameter,
        final String desc,
        final boolean visible)
    {
        checkEndMethod();
        checkDesc(desc, false);
        return new CheckAnnotationAdapter(mv.visitParameterAnnotation(parameter,