001/*
002 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.debug.internal;
024
025import java.util.*;
026
027/**
028 * Registry for allocating a globally unique integer id to each {@link DebugValue}.
029 */
030public class KeyRegistry {
031
032    private static final Map<String, Integer> keyMap = new HashMap<>();
033    private static final List<DebugValue> debugValues = new ArrayList<>();
034
035    /**
036     * Ensures a given debug value is registered.
037     *
038     * @return the globally unique id for {@code value}
039     */
040    public static synchronized int register(DebugValue value) {
041        String name = value.getName();
042        if (!keyMap.containsKey(name)) {
043            keyMap.put(name, debugValues.size());
044            debugValues.add(value);
045        }
046        return keyMap.get(name);
047    }
048
049    /**
050     * Gets a immutable view of the registered debug values.
051     *
052     * @return a list where {@code get(i).getIndex() == i}
053     */
054    public static synchronized List<DebugValue> getDebugValues() {
055        return Collections.unmodifiableList(debugValues);
056    }
057}