/*

 * Copyright (c) 2005, 2009, 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

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 * 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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/*

 *******************************************************************************

 * (C) Copyright IBM Corp. and others, 1996-2009 - All Rights Reserved         *

 *                                                                             *

 * The original version of this source code and documentation is copyrighted   *

 * and owned by IBM, These materials are provided under terms of a License     *

 * Agreement between IBM and Sun. This technology is protected by multiple     *

 * US and International patents. This notice and attribution to IBM may not    *

 * to removed.                                                                 *

 *******************************************************************************

*   file name:  UBiDiProps.java

*   encoding:   US-ASCII

*   tab size:   8 (not used)

*   indentation:4

*

*   created on: 2005jan16

*   created by: Markus W. Scherer

*

*   Low-level Unicode bidi/shaping properties access.

*   Java port of ubidi_props.h/.c.

*/

package sun.text.normalizer;

import java.io.BufferedInputStream;

import java.io.DataInputStream;

import java.io.InputStream;

import java.io.IOException;

public final class UBiDiProps {

    // constructors etc. --------------------------------------------------- ***

    // port of ubidi_openProps()

    public UBiDiProps() throws IOException{

        InputStream is=ICUData.getStream(DATA_FILE_NAME);

        BufferedInputStream b=new BufferedInputStream(is, 4096 /* data buffer size */);

        readData(b);

        b.close();

        is.close();

    }

    private void readData(InputStream is) throws IOException {

        DataInputStream inputStream=new DataInputStream(is);

        // read the header

        ICUBinary.readHeader(inputStream, FMT, new IsAcceptable());

        // read indexes[]

        int i, count;

        count=inputStream.readInt();

        if(count<IX_INDEX_TOP) {

            throw new IOException("indexes[0] too small in "+DATA_FILE_NAME);

        }

        indexes=new int[count];

        indexes[0]=count;

        for(i=1; i<count; ++i) {

            indexes[i]=inputStream.readInt();

        }

        // read the trie

        trie=new CharTrie(inputStream, null);

        // read mirrors[]

        count=indexes[IX_MIRROR_LENGTH];

        if(count>0) {

            mirrors=new int[count];

            for(i=0; i<count; ++i) {

                mirrors[i]=inputStream.readInt();

            }

        }

        // read jgArray[]

        count=indexes[IX_JG_LIMIT]-indexes[IX_JG_START];

        jgArray=new byte[count];

        for(i=0; i<count; ++i) {

            jgArray[i]=inputStream.readByte();

        }

    }

    // implement ICUBinary.Authenticate

    private final class IsAcceptable implements ICUBinary.Authenticate {

        public boolean isDataVersionAcceptable(byte version[]) {

            return version[0]==1 &&

                   version[2]==Trie.INDEX_STAGE_1_SHIFT_ && version[3]==Trie.INDEX_STAGE_2_SHIFT_;

        }

    }

    // UBiDiProps singleton

    private static UBiDiProps gBdp=null;

    // port of ubidi_getSingleton()

    public static final synchronized UBiDiProps getSingleton() throws IOException {

        if(gBdp==null) {

            gBdp=new UBiDiProps();

        }

        return gBdp;

    }

    // UBiDiProps dummy singleton

    private static UBiDiProps gBdpDummy=null;

    private UBiDiProps(boolean makeDummy) { // ignore makeDummy, only creates a unique signature

        indexes=new int[IX_TOP];

        indexes[0]=IX_TOP;

        trie=new CharTrie(0, 0, null); // dummy trie, always returns 0

    }

    /**

     * Get a singleton dummy object, one that works with no real data.

     * This can be used when the real data is not available.

     * Using the dummy can reduce checks for available data after an initial failure.

     * Port of ucase_getDummy().

     */

    public static final synchronized UBiDiProps getDummy() {

        if(gBdpDummy==null) {

            gBdpDummy=new UBiDiProps(true);

        }

        return gBdpDummy;

    }

    public final int getClass(int c) {

        return getClassFromProps(trie.getCodePointValue(c));

    }

    // data members -------------------------------------------------------- ***

    private int indexes[];

    private int mirrors[];

    private byte jgArray[];

    private CharTrie trie;

    // data format constants ----------------------------------------------- ***

    private static final String DATA_FILE_NAME = "/sun/text/resources/ubidi.icu";

    /* format "BiDi" */

    private static final byte FMT[]={ 0x42, 0x69, 0x44, 0x69 };

    /* indexes into indexes[] */

    private static final int IX_INDEX_TOP=0;

    private static final int IX_MIRROR_LENGTH=3;

    private static final int IX_JG_START=4;

    private static final int IX_JG_LIMIT=5;

    private static final int IX_TOP=16;

    private static final int CLASS_MASK=    0x0000001f;

    private static final int getClassFromProps(int props) {

        return props&CLASS_MASK;

    }

}