1/*
2 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23package org.graalvm.compiler.debug.internal;
24
25import java.util.ArrayList;
26import java.util.Collections;
27import java.util.HashMap;
28import java.util.List;
29import java.util.Map;
30
31/**
32 * Registry for allocating a globally unique integer id to each {@link DebugValue}.
33 */
34public class KeyRegistry {
35
36    private static final Map<String, Integer> keyMap = new HashMap<>();
37    private static final List<DebugValue> debugValues = new ArrayList<>();
38
39    /**
40     * Ensures a given debug value is registered.
41     *
42     * @return the globally unique id for {@code value}
43     */
44    public static synchronized int register(DebugValue value) {
45        String name = value.getName();
46        if (!keyMap.containsKey(name)) {
47            keyMap.put(name, debugValues.size());
48            debugValues.add(value);
49        }
50        return keyMap.get(name);
51    }
52
53    /**
54     * Gets a immutable view of the registered debug values.
55     *
56     * @return a list where {@code get(i).getIndex() == i}
57     */
58    public static synchronized List<DebugValue> getDebugValues() {
59        return Collections.unmodifiableList(debugValues);
60    }
61}
62