drawinggrouprecord.java

来自「java 报表 to office文档： 本包由java语言开发」· Java 代码 · 共 147 行

/* ====================================================================
   Copyright 2003-2004   Apache Software Foundation

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
==================================================================== */

package org.apache.poi.hssf.record;

import org.apache.poi.ddf.EscherRecord;
import org.apache.poi.ddf.NullEscherSerializationListener;
import org.apache.poi.util.ArrayUtil;
import org.apache.poi.util.LittleEndian;

import java.util.Iterator;
import java.util.List;


public class DrawingGroupRecord extends AbstractEscherHolderRecord
{
    public static final short sid = 0xEB;

    static final int MAX_RECORD_SIZE = 8228;
    private static final int MAX_DATA_SIZE = MAX_RECORD_SIZE - 4;

    public DrawingGroupRecord()
    {
    }

    public DrawingGroupRecord( short id, short size, byte[] data )
    {
        super( id, size, data );
    }

    public DrawingGroupRecord( short id, short size, byte[] data, int offset )
    {
        super( id, size, data, offset );
    }

    protected String getRecordName()
    {
        return "MSODRAWINGGROUP";
    }

    public short getSid()
    {
        return sid;
    }

    public int serialize(int offset, byte[] data)
    {
        byte[] rawData = getRawData();
        if (getEscherRecords().size() == 0 && rawData != null)
        {
            return writeData( offset, data, rawData );
        }
        else
        {
            byte[] buffer = new byte[getRawDataSize()];
            int pos = 0;
            for ( Iterator iterator = getEscherRecords().iterator(); iterator.hasNext(); )
            {
                EscherRecord r = (EscherRecord) iterator.next();
                pos += r.serialize(pos, buffer, new NullEscherSerializationListener() );
            }

            return writeData( offset, data, buffer );
        }
    }

    /**
     * Size of record (including 4 byte headers for all sections)
     */
    public int getRecordSize()
    {
        return grossSizeFromDataSize( getRawDataSize() );
    }

    public int getRawDataSize()
    {
        List escherRecords = getEscherRecords();
        byte[] rawData = getRawData();
        if (escherRecords.size() == 0 && rawData != null)
        {
            return rawData.length;
        }
        else
        {
            int size = 0;
            for ( Iterator iterator = escherRecords.iterator(); iterator.hasNext(); )
            {
                EscherRecord r = (EscherRecord) iterator.next();
                size += r.getRecordSize();
            }
            return size;
        }
    }

    static int grossSizeFromDataSize(int dataSize)
    {
        return dataSize + ( (dataSize - 1) / MAX_DATA_SIZE + 1 ) * 4;
    }

    private int writeData( int offset, byte[] data, byte[] rawData )
    {
        int writtenActualData = 0;
        int writtenRawData = 0;
        while (writtenRawData < rawData.length)
        {
            int segmentLength = Math.min( rawData.length - writtenRawData, MAX_DATA_SIZE);
            if (writtenRawData / MAX_DATA_SIZE >= 2)
                writeContinueHeader( data, offset, segmentLength );
            else
                writeHeader( data, offset, segmentLength );
            writtenActualData += 4;
            offset += 4;
            ArrayUtil.arraycopy( rawData, writtenRawData, data, offset, segmentLength );
            offset += segmentLength;
            writtenRawData += segmentLength;
            writtenActualData += segmentLength;
        }
        return writtenActualData;
    }

    private void writeHeader( byte[] data, int offset, int sizeExcludingHeader )
    {
        LittleEndian.putShort(data, 0 + offset, getSid());
        LittleEndian.putShort(data, 2 + offset, (short) sizeExcludingHeader);
    }

    private void writeContinueHeader( byte[] data, int offset, int sizeExcludingHeader )
    {
        LittleEndian.putShort(data, 0 + offset, ContinueRecord.sid);
        LittleEndian.putShort(data, 2 + offset, (short) sizeExcludingHeader);
    }

}