methodvisitor.java

jboss规则引擎

/***
 * 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.drools.asm;

/**
 * A visitor to visit a Java method. The methods of this interface must be
 * called in the following order: [ <tt>visitAnnotationDefault</tt> ] (
 * <tt>visitAnnotation</tt> | <tt>visitParameterAnnotation</tt> |
 * <tt>visitAttribute</tt> )* [ <tt>visitCode</tt> ( <tt>visit</tt><i>X</i>Insn</tt> |
 * <tt>visitLabel</tt> | <tt>visitTryCatchBlock</tt> | <tt>visitLocalVariable</tt> |
 * <tt>visitLineNumber</tt>)* <tt>visitMaxs</tt> ] <tt>visitEnd</tt>. In
 * addition, the <tt>visit</tt><i>X</i>Insn</tt> and <tt>visitLabel</tt>
 * methods must be called in the sequential order of the bytecode instructions
 * of the visited code, and the <tt>visitLocalVariable</tt> and <tt>visitLineNumber</tt>
 * methods must be called <i>after</i> the labels passed as arguments have been
 * visited.
 * 
 * @author Eric Bruneton
 */
public interface MethodVisitor {

    // -------------------------------------------------------------------------
    // Annotations and non standard attributes
    // -------------------------------------------------------------------------

    /**
     * Visits the default value of this annotation interface method.
     * 
     * @return a non null visitor to the visit the actual default value of this
     *         annotation interface method. The 'name' parameters passed to the
     *         methods of this annotation visitor are ignored. Moreover, exacly
     *         one visit method must be called on this annotation visitor,
     *         followed by visitEnd.
     */
    AnnotationVisitor visitAnnotationDefault();

    /**
     * Visits an annotation of this method.
     * 
     * @param desc the class descriptor of the annotation class.
     * @param visible <tt>true</tt> if the annotation is visible at runtime.
     * @return a non null visitor to visit the annotation values.
     */
    AnnotationVisitor visitAnnotation(String desc,
                                      boolean visible);

    /**
     * Visits an annotation of a parameter this method.
     * 
     * @param parameter the parameter index.
     * @param desc the class descriptor of the annotation class.
     * @param visible <tt>true</tt> if the annotation is visible at runtime.
     * @return a non null visitor to visit the annotation values.
     */
    AnnotationVisitor visitParameterAnnotation(int parameter,
                                               String desc,
                                               boolean visible);

    /**
     * Visits a non standard attribute of this method.
     * 
     * @param attr an attribute.
     */
    void visitAttribute(Attribute attr);

    /**
     * Starts the visit of the method's code, if any (i.e. non abstract method).
     */
    void visitCode();

    // -------------------------------------------------------------------------
    // Normal instructions
    // -------------------------------------------------------------------------

    /**
     * Visits a zero operand instruction.
     * 
     * @param opcode the opcode of the instruction to be visited. This opcode is
     *        either NOP, ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2,
     *        ICONST_3, ICONST_4, ICONST_5, LCONST_0, LCONST_1, FCONST_0,
     *        FCONST_1, FCONST_2, DCONST_0, DCONST_1, IALOAD, LALOAD, FALOAD,
     *        DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IASTORE, LASTORE, FASTORE,
     *        DASTORE, AASTORE, BASTORE, CASTORE, SASTORE, POP, POP2, DUP,
     *        DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP, IADD, LADD, FADD,
     *        DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, LDIV,
     *        FDIV, DDIV, IREM, LREM, FREM, DREM, INEG, LNEG, FNEG, DNEG, ISHL,
     *        LSHL, ISHR, LSHR, IUSHR, LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR,
     *        I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, F2D, D2I, D2L, D2F, I2B,
     *        I2C, I2S, LCMP, FCMPL, FCMPG, DCMPL, DCMPG, IRETURN, LRETURN,
     *        FRETURN, DRETURN, ARETURN, RETURN, ARRAYLENGTH, ATHROW,
     *        MONITORENTER, or MONITOREXIT.
     */
    void visitInsn(int opcode);

    /**
     * Visits an instruction with a single int operand.
     * 
     * @param opcode the opcode of the instruction to be visited. This opcode is
     *        either BIPUSH, SIPUSH or NEWARRAY.
     * @param operand the operand of the instruction to be visited.<br>
     *        When opcode is BIPUSH, operand value should be between
     *        Byte.MIN_VALUE and Byte.MAX_VALUE.<br>
     *        When opcode is SIPUSH, operand value should be between
     *        Short.MIN_VALUE and Short.MAX_VALUE.<br>
     *        When opcode is NEWARRAY, operand value should be one of
     *        {@link Opcodes#T_BOOLEAN}, {@link Opcodes#T_CHAR},
     *        {@link Opcodes#T_FLOAT}, {@link Opcodes#T_DOUBLE},
     *        {@link Opcodes#T_BYTE}, {@link Opcodes#T_SHORT},
     *        {@link Opcodes#T_INT} or {@link Opcodes#T_LONG}.
     */
    void visitIntInsn(int opcode,
                      int operand);

    /**
     * Visits a local variable instruction. A local variable instruction is an
     * instruction that loads or stores the value of a local variable.
     * 
     * @param opcode the opcode of the local variable instruction to be visited.
     *        This opcode is either ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE,
     *        LSTORE, FSTORE, DSTORE, ASTORE or RET.
     * @param var the operand of the instruction to be visited. This operand is
     *        the index of a local variable.
     */
    void visitVarInsn(int opcode,
                      int var);

    /**
     * Visits a type instruction. A type instruction is an instruction that
     * takes a type descriptor as parameter.
     * 
     * @param opcode the opcode of the type instruction to be visited. This
     *        opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF.
     * @param desc the operand of the instruction to be visited. This operand is
     *        must be a fully qualified class name in internal form, or the type
     *        descriptor of an array type (see {@link Type Type}).
     */
    void visitTypeInsn(int opcode,
                       String desc);

    /**
     * Visits a field instruction. A field instruction is an instruction that
     * loads or stores the value of a field of an object.
     * 
     * @param opcode the opcode of the type instruction to be visited. This
     *        opcode is either GETSTATIC, PUTSTATIC, GETFIELD or PUTFIELD.
     * @param owner the internal name of the field's owner class (see {@link
     *        Type#getInternalName() getInternalName}).
     * @param name the field's name.
     * @param desc the field's descriptor (see {@link Type Type}).
     */
    void visitFieldInsn(int opcode,