/*

 * Copyright (c) 2001, 2015, 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.  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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 */

package sun.text;

import sun.text.normalizer.NormalizerBase;

import sun.text.normalizer.NormalizerImpl;

public final class ComposedCharIter {

    /**

     * Constant that indicates the iteration has completed.

     * {@link #next} returns this value when there are no more composed characters

     * over which to iterate.

     */

    public static final int DONE = NormalizerBase.DONE;

    //cache the decomps mapping, so the seconde composedcharIter does

    //not need to get the data again.

    private static int chars[];

    private static String decomps[];

    private static int decompNum;

    static {

        int maxNum = 2100;

        chars = new int[maxNum];

        decomps = new String[maxNum];

        decompNum = NormalizerImpl.getDecompose(chars, decomps);

    }

    /**

     * Construct a new {@code ComposedCharIter}.  The iterator will return

     * all Unicode characters with canonical decompositions, excluding Korean

     * Hangul characters.

     */

    public ComposedCharIter() { }

    /**

     * Returns the next precomposed Unicode character.

     * Repeated calls to {@code next} return all of the precomposed characters defined

     * by Unicode, in ascending order.  After all precomposed characters have

     * been returned, {@link #hasNext} will return {@code false} and further calls

     * to {@code next} will return {@link #DONE}.

     */

    public int next() {

        if (curChar == decompNum - 1) {

            return DONE;

        }

        return chars[++curChar];

    }

    /**

     * Returns the Unicode decomposition of the current character.

     * This method returns the decomposition of the precomposed character most

     * recently returned by {@link #next}.  The resulting decomposition is

     * affected by the settings of the options passed to the constructor.

     */

    public String decomposition() {

        return decomps[curChar];

    }

    private int curChar = -1;

}