ConstBasic.java

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package com.sun.jdo.api.persistence.enhancer.classfile;

import java.io.*;

/**
 * Abstract base class of the types which represent entries in
 * the class constant pool.
 */

abstract public class ConstBasic implements VMConstants {
  /* The index of the constant entry in the constant pool */
  protected int index = 0;

  /* public accessors */

  /* Get the index of this constant entry */
  public int getIndex() { return index; }

  /* Return the type of the constant entry - see VMConstants */
  public abstract int tag ();

  /* package local methods */

  /**
   * Sets the index of this constant with its containing constant pool
   */
  void setIndex(int ind) { index = ind; }

  /**
   * Write this Constant pool entry to the output stream
   */
  abstract void formatData (DataOutputStream b) throws IOException;

  /**
   * Resolve integer index references to the actual constant pool
   * entries that they represent.  This is used during class file 
   * reading because a constant pool entry could have a forward
   * reference to a higher numbered constant.
   */
  abstract void resolve (ConstantPool p);

  /**
   * Return the index of this constant in the constant pool as
   * a decimal formatted String.
   */
  String indexAsString() { return Integer.toString(index); }

  /**
   * The constructor for subtypes
   */
  ConstBasic () {}
}