| /* |
| * Copyright (c) 2003, 2017, 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.utilities; |
| |
| import java.util.*; |
| import sun.jvm.hotspot.debugger.*; |
| import sun.jvm.hotspot.types.*; |
| import sun.jvm.hotspot.oops.*; |
| import sun.jvm.hotspot.runtime.*; |
| |
| public class Hashtable extends BasicHashtable { |
| static { |
| VM.registerVMInitializedObserver(new Observer() { |
| public void update(Observable o, Object data) { |
| initialize(VM.getVM().getTypeDataBase()); |
| } |
| }); |
| } |
| |
| private static synchronized void initialize(TypeDataBase db) { |
| // just to confirm that type exists |
| Type type = db.lookupType("IntptrHashtable"); |
| } |
| |
| // derived class may return Class<? extends HashtableEntry> |
| protected Class getHashtableEntryClass() { |
| return HashtableEntry.class; |
| } |
| |
| public int computeHash(Symbol name) { |
| return (int) name.identityHash(); |
| } |
| |
| public int hashToIndex(long fullHash) { |
| return (int) (fullHash % tableSize()); |
| } |
| |
| public Hashtable(Address addr) { |
| super(addr); |
| } |
| |
| // VM's Hashtable::hash_symbol |
| protected static long hashSymbol(byte[] buf) { |
| long h = 0; |
| int s = 0; |
| int len = buf.length; |
| while (len-- > 0) { |
| h = 31*h + (0xFFL & buf[s]); |
| s++; |
| } |
| return h & 0xFFFFFFFFL; |
| } |
| } |