src/java.xml.bind/share/classes/com/sun/xml/internal/fastinfoset/util/StringIntMap.java

/*
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 * 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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
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 * THIS FILE WAS MODIFIED BY SUN MICROSYSTEMS, INC.
 */

package com.sun.xml.internal.fastinfoset.util;

import com.sun.xml.internal.fastinfoset.CommonResourceBundle;

public class StringIntMap extends KeyIntMap {
    protected static final Entry NULL_ENTRY = new Entry(null, 0, -1, null);

    protected StringIntMap _readOnlyMap;

    protected static class Entry extends BaseEntry {
        final String _key;
        Entry _next;

        public Entry(String key, int hash, int value, Entry next) {
            super(hash, value);
            _key = key;
            _next = next;
        }
    }

    protected Entry _lastEntry = NULL_ENTRY;

    protected Entry[] _table;

    protected int _index;

    // Total character count of Map
    protected int _totalCharacterCount;

    public StringIntMap(int initialCapacity, float loadFactor) {
        super(initialCapacity, loadFactor);

        _table = new Entry[_capacity];
    }

    public StringIntMap(int initialCapacity) {
        this(initialCapacity, DEFAULT_LOAD_FACTOR);
    }

    public StringIntMap() {
        this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR);
    }

    public void clear() {
        for (int i = 0; i < _table.length; i++) {
            _table[i] = null;
        }
        _lastEntry = NULL_ENTRY;
        _size = 0;
        _index = _readOnlyMapSize;
        _totalCharacterCount = 0;
    }

    public void setReadOnlyMap(KeyIntMap readOnlyMap, boolean clear) {
        if (!(readOnlyMap instanceof StringIntMap)) {
            throw new IllegalArgumentException(CommonResourceBundle.getInstance().
                    getString("message.illegalClass", new Object[]{readOnlyMap}));
        }

        setReadOnlyMap((StringIntMap)readOnlyMap, clear);
    }

    public final void setReadOnlyMap(StringIntMap readOnlyMap, boolean clear) {
        _readOnlyMap = readOnlyMap;
        if (_readOnlyMap != null) {
            _readOnlyMapSize = _readOnlyMap.size();
            _index = _size + _readOnlyMapSize;

            if (clear) {
                clear();
            }
        }  else {
            _readOnlyMapSize = 0;
            _index = _size;
        }
    }

    public final int getNextIndex() {
        return _index++;
    }

    public final int getIndex() {
        return _index;
    }

    public final int obtainIndex(String key) {
        final int hash = hashHash(key.hashCode());

        if (_readOnlyMap != null) {
            final int index = _readOnlyMap.get(key, hash);
            if (index != -1) {
                return index;
            }
        }

        final int tableIndex = indexFor(hash, _table.length);
        for (Entry e = _table[tableIndex]; e != null; e = e._next) {
            if (e._hash == hash && eq(key, e._key)) {
                return e._value;
            }
        }

        addEntry(key, hash, tableIndex);
        return NOT_PRESENT;
    }

    public final void add(String key) {
        final int hash = hashHash(key.hashCode());
        final int tableIndex = indexFor(hash, _table.length);
        addEntry(key, hash, tableIndex);
    }

    public final int get(String key) {
        if (key == _lastEntry._key)
            return _lastEntry._value;

        return get(key, hashHash(key.hashCode()));
    }

    public final int getTotalCharacterCount() {
        return _totalCharacterCount;
    }

    private final int get(String key, int hash) {
        if (_readOnlyMap != null) {
            final int i = _readOnlyMap.get(key, hash);
            if (i != -1) {
                return i;
            }
        }

        final int tableIndex = indexFor(hash, _table.length);
        for (Entry e = _table[tableIndex]; e != null; e = e._next) {
            if (e._hash == hash && eq(key, e._key)) {
                _lastEntry = e;
                return e._value;
            }
        }

        return NOT_PRESENT;
    }


    private final void addEntry(String key, int hash, int bucketIndex) {
        Entry e = _table[bucketIndex];
        _table[bucketIndex] = new Entry(key, hash, _index++, e);
        _totalCharacterCount += key.length();
        if (_size++ >= _threshold) {
            resize(2 * _table.length);
        }
    }

    protected final void resize(int newCapacity) {
        _capacity = newCapacity;
        Entry[] oldTable = _table;
        int oldCapacity = oldTable.length;
        if (oldCapacity == MAXIMUM_CAPACITY) {
            _threshold = Integer.MAX_VALUE;
            return;
        }

        Entry[] newTable = new Entry[_capacity];
        transfer(newTable);
        _table = newTable;
        _threshold = (int)(_capacity * _loadFactor);
    }

    private final void transfer(Entry[] newTable) {
        Entry[] src = _table;
        int newCapacity = newTable.length;
        for (int j = 0; j < src.length; j++) {
            Entry e = src[j];
            if (e != null) {
                src[j] = null;
                do {
                    Entry next = e._next;
                    int i = indexFor(e._hash, newCapacity);
                    e._next = newTable[i];
                    newTable[i] = e;
                    e = next;
                } while (e != null);
            }
        }
    }

    private final boolean eq(String x, String y) {
        return x == y || x.equals(y);
    }
}