gcc/libjava/gnu/classpath/jdwp/VMFrame.java

/* VMFrame.java -- Reference implementation of VM hooks for JDWP Frame access.
   Copyright (C) 2005, 2006, 2007 Free Software Foundation

This file is part of GNU Classpath.

GNU Classpath 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 2, or (at your option)
any later version.

GNU Classpath 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 GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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independent module, the terms and conditions of the license of that
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or based on this library.  If you modify this library, you may extend
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exception statement from your version. */


package gnu.classpath.jdwp;

import gnu.classpath.jdwp.util.Location;

/**
 * Reference implementation of VM hooks for JDWP Frame access.
 * 
 * @author aluchko 
 */

public class VMFrame
{
  /**
   * Returns the size of a frame ID over JDWP
   */
  public static final int SIZE = 8;

  // The thread this frame resides in
  private Thread thread;
   
  //The object of this frame
  private Object obj;
  
  // The current location of this frame
  private Location loc;
  
  // id of this frame
  private long id;
  
  /**
   * Create a new VMFrame object.
   * 
   * @param thr a Thread, the thread this frame is in
   * @param frame_id a long, the jframeID of this frame
   * @param frame_loc a Location, the location of this frame
   */
  public VMFrame(Thread thr, long frame_id, Location frame_loc)
  {
    thread = thr;
    id = frame_id;
    loc = frame_loc;
  }
  
  /**
   * Gets the current location of the frame.
   */
  public Location getLocation()
  {
    return loc;
  }

  /**
   * Returns the value of the variable in the given slot.
   * 
   * @param slot the slot containing the variable
   */
  public native Object getValue(int slot);

  /**
   * Assigns the given variable to the given value. 
   * @param slot The slot which contains the variable
   * @param value The value to assign the variable to
   */
  public native void setValue(int slot, Object value);
  
  /**
   * Get the thread this frame is in.
   */
  public Thread getThread()
  {
    return thread;
  }

  /**
   * Get the object which is represented by 'this' in the context of the frame,
   * returns null if the method is native or static.
   */
  public Object getObject()
  {
    return obj;
  }

  /**
   * Get the frameID
   * @return an id which is unique within the scope of the VM
   */
  public long getId()
  {
    return id;
  }

}