/*

 * Copyright 2000-2009 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

package sun.jvm.hotspot.code;

import java.util.*;

import sun.jvm.hotspot.debugger.*;

import sun.jvm.hotspot.runtime.VM;

import sun.jvm.hotspot.utilities.*;

public class DebugInfoReadStream extends CompressedReadStream {

  private NMethod code;

  private int InvocationEntryBCI;

  private List objectPool; // ArrayList<ObjectValue>

  public DebugInfoReadStream(NMethod code, int offset) {

    super(code.scopesDataBegin(), offset);

    InvocationEntryBCI = VM.getVM().getInvocationEntryBCI();

    this.code = code;

    this.objectPool = null;

  }

  public DebugInfoReadStream(NMethod code, int offset, List objectPool) {

    super(code.scopesDataBegin(), offset);

    InvocationEntryBCI = VM.getVM().getInvocationEntryBCI();

    this.code = code;

    this.objectPool = objectPool;

  }

  public OopHandle readOopHandle() {

    return code.getOopAt(readInt());

  }

  ScopeValue readObjectValue() {

    int id = readInt();

    if (Assert.ASSERTS_ENABLED) {

      Assert.that(objectPool != null, "object pool does not exist");

      for (Iterator itr = objectPool.iterator(); itr.hasNext();) {

        ObjectValue ov = (ObjectValue) itr.next();

        Assert.that(ov.id() != id, "should not be read twice");

      }

    }

    ObjectValue result = new ObjectValue(id);

    // Cache the object since an object field could reference it.

    objectPool.add(result);

    result.readObject(this);

    return result;

  }

  ScopeValue getCachedObject() {

    int id = readInt();

    Assert.that(objectPool != null, "object pool does not exist");

    for (Iterator itr = objectPool.iterator(); itr.hasNext();) {

      ObjectValue ov = (ObjectValue) itr.next();

      if (ov.id() == id) {

        return ov;

      }

    }

    Assert.that(false, "should not reach here");

    return null;

  }

}