Source for gnu.classpath.jdwp.processor.StackFrameCommandSet

   1: /* StackFrameCommandSet.java -- class to implement the StackFrame Command Set
   2:    Copyright (C) 2005 Free Software Foundation
   3:  
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: terms of your choice, provided that you also meet, for each linked
  32: independent module, the terms and conditions of the license of that
  33: module.  An independent module is a module which is not derived from
  34: or based on this library.  If you modify this library, you may extend
  35: this exception to your version of the library, but you are not
  36: obligated to do so.  If you do not wish to do so, delete this
  37: exception statement from your version. */
  38: 
  39: 
  40: package gnu.classpath.jdwp.processor;
  41: 
  42: import gnu.classpath.jdwp.JdwpConstants;
  43: import gnu.classpath.jdwp.VMFrame;
  44: import gnu.classpath.jdwp.VMVirtualMachine;
  45: import gnu.classpath.jdwp.exception.JdwpException;
  46: import gnu.classpath.jdwp.exception.JdwpInternalErrorException;
  47: import gnu.classpath.jdwp.exception.NotImplementedException;
  48: import gnu.classpath.jdwp.id.ObjectId;
  49: import gnu.classpath.jdwp.util.Value;
  50: 
  51: import java.io.DataOutputStream;
  52: import java.io.IOException;
  53: import java.nio.ByteBuffer;
  54: 
  55: /**
  56:  * A class representing the StackFrame Command Set.
  57:  * 
  58:  * @author Aaron Luchko <aluchko@redhat.com>
  59:  */
  60: public class StackFrameCommandSet
  61:   extends CommandSet
  62: {
  63:   public boolean runCommand(ByteBuffer bb, DataOutputStream os, byte command)
  64:       throws JdwpException
  65:   {
  66:     boolean keepRunning = true;
  67:     try
  68:       {
  69:         switch (command)
  70:           {
  71:           case JdwpConstants.CommandSet.StackFrame.GET_VALUES:
  72:             executeGetValues(bb, os);
  73:             break;
  74:           case JdwpConstants.CommandSet.StackFrame.SET_VALUES:
  75:             executeSetValues(bb, os);
  76:             break;
  77:           case JdwpConstants.CommandSet.StackFrame.THIS_OBJECT:
  78:             executeThisObject(bb, os);
  79:             break;
  80:           case JdwpConstants.CommandSet.StackFrame.POP_FRAMES:
  81:             executePopFrames(bb, os);
  82:             break;
  83:           default:
  84:             throw new NotImplementedException("Command " + command + 
  85:             " not found in Stack Frame Command Set.");
  86:           }
  87:       }
  88:     catch (IOException ex)
  89:       {
  90:         // The DataOutputStream we're using isn't talking to a socket at all
  91:         // So if we throw an IOException we're in serious trouble
  92:         throw new JdwpInternalErrorException(ex);
  93:       }
  94: 
  95:     return false;
  96:   }
  97: 
  98:   private void executeGetValues(ByteBuffer bb, DataOutputStream os)
  99:       throws JdwpException, IOException
 100:   {
 101:     ObjectId tId = idMan.readObjectId(bb);
 102:     Thread thread = (Thread) tId.getObject();
 103: 
 104:     // Although Frames look like other ids they are not. First they are not
 105:     // ObjectIds since they don't exist in the users code. Storing them as an
 106:     // ObjectId would mean they could be garbage collected since no one else
 107:     // has a reference to them. Furthermore they are not ReferenceTypeIds since
 108:     // these are held permanently and we want these to be held only as long as
 109:     // the Thread is suspended.
 110:     VMFrame frame = VMVirtualMachine.getFrame(thread, bb);
 111:     int slots = bb.getInt();
 112:     os.writeInt(slots); // Looks pointless but this is the protocol
 113:     for (int i = 0; i < slots; i++)
 114:       {
 115:         int slot = bb.getInt();
 116:         byte sig = bb.get();
 117:         Object val = frame.getValue(slot);
 118:         Value.writeTaggedValue(os, val);
 119:       }
 120:   }
 121: 
 122:   private void executeSetValues(ByteBuffer bb, DataOutputStream os)
 123:       throws JdwpException, IOException
 124:   {
 125:     ObjectId tId = idMan.readObjectId(bb);
 126:     Thread thread = (Thread) tId.getObject();
 127: 
 128:     VMFrame frame = VMVirtualMachine.getFrame(thread, bb);
 129: 
 130:     int slots = bb.getInt();
 131:     for (int i = 0; i < slots; i++)
 132:       {
 133:         int slot = bb.getInt();
 134:         Object value = Value.getObj(bb);
 135:         frame.setValue(slot, value);
 136:       }
 137:   }
 138: 
 139:   private void executeThisObject(ByteBuffer bb, DataOutputStream os)
 140:       throws JdwpException, IOException
 141:   {
 142:     ObjectId tId = idMan.readObjectId(bb);
 143:     Thread thread = (Thread) tId.getObject();
 144: 
 145:     VMFrame frame = VMVirtualMachine.getFrame(thread, bb);
 146: 
 147:     Object thisObject = frame.getObject();
 148:     Value.writeTaggedValue(os, thisObject);
 149:   }
 150: 
 151:   private void executePopFrames(ByteBuffer bb, DataOutputStream os)
 152:       throws JdwpException
 153:   {
 154:     // This command is optional, determined by VirtualMachines CapabilitiesNew
 155:     // so we'll leave it till later to implement
 156:     throw new NotImplementedException("Command PopFrames not implemented.");
 157:   }
 158: }