/*

 * Copyright (c) 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

package sun.jvm.hotspot.runtime;

import java.io.*;

import java.util.*;

import sun.jvm.hotspot.debugger.*;

import sun.jvm.hotspot.memory.*;

import sun.jvm.hotspot.oops.*;

import sun.jvm.hotspot.runtime.*;

import sun.jvm.hotspot.types.*;

import sun.jvm.hotspot.utilities.*;

public class vmSymbols {

  static {

    VM.registerVMInitializedObserver(new Observer() {

        public void update(Observable o, Object data) {

          initialize(VM.getVM().getTypeDataBase());

        }

      });

  }

  private static Address symbolsAddress;

  private static int FIRST_SID;

  private static int SID_LIMIT;

  private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {

    Type type            = db.lookupType("vmSymbols");

    symbolsAddress       = type.getAddressField("_symbols[0]").getStaticFieldAddress();

    FIRST_SID            = db.lookupIntConstant("vmSymbols::FIRST_SID");

    SID_LIMIT            = db.lookupIntConstant("vmSymbols::SID_LIMIT");

  }

  public static Symbol symbolAt(int id) {

    if (id < FIRST_SID || id >= SID_LIMIT) throw new IndexOutOfBoundsException("bad SID " + id);

    return Symbol.create(symbolsAddress.getAddressAt(id * VM.getVM().getAddressSize()));

  }

}