/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

package com.sun.org.apache.bcel.internal.generic;

import com.sun.org.apache.bcel.internal.classfile.*;

/**

 * This class represents a line number within a method, i.e., give an instruction

 * a line number corresponding to the source code line.

 *

 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>

 * @see     LineNumber

 * @see     MethodGen

 */

public class LineNumberGen

  implements InstructionTargeter, Cloneable, java.io.Serializable

{

  private InstructionHandle ih;

  private int               src_line;

  /**

   * Create a line number.

   *

   * @param ih instruction handle to reference

   */

  public LineNumberGen(InstructionHandle ih, int src_line) {

    setInstruction(ih);

    setSourceLine(src_line);

  }

  /**

   * @return true, if ih is target of this line number

   */

  @Override

  public boolean containsTarget(InstructionHandle ih) {

    return this.ih == ih;

  }

  /**

   * @param old_ih old target

   * @param new_ih new target

   */

  @Override

  public void updateTarget(InstructionHandle old_ih, InstructionHandle new_ih) {

    if(old_ih != ih)

      throw new ClassGenException("Not targeting " + old_ih + ", but " + ih + "}");

    else

      setInstruction(new_ih);

  }

  /**

   * Get LineNumber attribute .

   *

   * This relies on that the instruction list has already been dumped to byte code or

   * or that the `setPositions' methods has been called for the instruction list.

   */

  public LineNumber getLineNumber() {

    return new LineNumber(ih.getPosition(), src_line);

  }

  public final void setInstruction(InstructionHandle ih) {

    BranchInstruction.notifyTargetChanging(this.ih, this);

    this.ih = ih;

    BranchInstruction.notifyTargetChanged(this.ih, this);

  }

  @Override

  public Object clone() {

    try {

      return super.clone();

    } catch(CloneNotSupportedException e) {

      System.err.println(e);

      return null;

    }

  }

  public InstructionHandle getInstruction()               { return ih; }

  public void              setSourceLine(int src_line)    { this.src_line = src_line; }

  public int               getSourceLine()                { return src_line; }

}