content: /*
   *  This file is part of AndroidIDE.
   *
   *  AndroidIDE is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  AndroidIDE is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *   along with AndroidIDE.  If not, see <https://www.gnu.org/licenses/>.
   */
  
  /*
   * reserved comment block
   * DO NOT REMOVE OR ALTER!
   */
  /*
   * Copyright 2001-2004 The Apache Software Foundation.
   *
   * 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.
   */
  
  /*
   * $Id: MethodGenerator.java,v 1.10 2010-11-01 04:34:19 joehw Exp $
   */
  package jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util;
  import java.io.DataOutputStream;
  import java.io.IOException;
  
  import jaxp.sun.org.apache.bcel.internal.Constants;
  import jaxp.sun.org.apache.bcel.internal.generic.ClassGen;
  import jaxp.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
  import jaxp.sun.org.apache.bcel.internal.generic.Instruction;
  import jaxp.sun.org.apache.bcel.internal.generic.InstructionList;
  import jaxp.sun.org.apache.bcel.internal.generic.Visitor;
  
  /**
   * A special abstract dummy subclass of
   * {@link org.apache.bcel.generic.Instruction} used to mark locations of
   * interest in an {@link InstructionList}.  It and
   * its subclasses are only used as placeholders, and do not contribute to the
   * actual byte code instruction stream.
   */
  abstract class MarkerInstruction extends Instruction {
      /**
       * Zero-argument constructor.  Sets the opcode to an invalid value and
       * sets the length to zero, as it will not be written as part of the
       * generated byte code.
       */
      public MarkerInstruction() {
          super(Constants.UNDEFINED, (short) 0);
      }
  
      /**
       * {@link Visitor}s will know nothing about this
       * kind of {@link org.apche.bcel.generic.Instruction}, so this method does
       * nothing.
       */
      public void accept(Visitor v) {
      }
  
      /**
       * The number of JVM stack entries consumed by the instruction.
       * This instruction is just a place holder, so it does not consume any
       * stack entries.
       * @param cpg The {@link ConstantPoolGen} for the
       * current {@link ClassGen}
       * @return <code>0</code> always
       */
      final public int consumeStack(ConstantPoolGen cpg) {
          return 0;
      }
      /**
       * The number of JVM stack entries produced by the instruction.
       * This instruction is just a place holder, so it does not produce any
       * stack entries.
       * @param cpg The {@link ConstantPoolGen} for the
       * current {@link ClassGen}
       * @return <code>0</code> always
       */
      final public int produceStack(ConstantPoolGen cpg) {
          return 0;
      }
  
      /**
       * Produce a copy of the instruction.  By default a
       * {@link MarkerInstruction} has no parameters, so the base implementation
       * of {@link #copy()} returns the instruction itself.
       * @return The instruction itself.
       */
      public Instruction copy() {
          return this;
      }
      /**
       * Dump instruction as byte code to stream out.  A {@link MarkerInstruction}
       * has no effect on the generated byte code so it is never emitted to the
       * output stream.
       * @param out Output stream
       */
      final public void dump(DataOutputStream out) throws IOException {
      }
  }
  