Application: gvSIG desktop

package org.gvsig.fmap.dal.file.bsq;

import java.io.File;

import java.io.IOException;

import java.io.RandomAccessFile;

import java.nio.Buffer;

import java.nio.ByteBuffer;

import java.nio.ByteOrder;

import java.nio.DoubleBuffer;

import java.nio.FloatBuffer;

import java.nio.IntBuffer;

import java.nio.ShortBuffer;

import org.apache.commons.io.IOUtils;

import org.gvsig.raster.lib.buffer.api.BandInfo;

import org.gvsig.raster.lib.buffer.api.BandPageManager;

import org.gvsig.raster.lib.buffer.api.BufferLocator;

import org.gvsig.raster.lib.buffer.api.BufferManager;

import org.gvsig.tools.dispose.impl.AbstractDisposable;

import org.gvsig.tools.exception.BaseException;

public class BSQBandPageManager extends AbstractDisposable implements BandPageManager {

    private RandomAccessFile  raf;

    private final int rows;

    private final int columns;

    private final int dataType;

    private final File file;

    private final long startpos;

    private final ByteOrder byteOrder;

    /**

     * @param file

     * @param startpos

     * @param rows

     * @param columns

     * @param dataType

     * @param byteOrder

     * @throws IOException

     */

    public BSQBandPageManager(File file, long startpos, int rows, int columns, int dataType, ByteOrder  byteOrder) throws IOException {

        this.rows = rows;

        this.columns = columns;

        this.dataType = dataType;

        this.file = file;

        this.startpos = startpos;

        this.byteOrder = byteOrder;

        this.raf = new RandomAccessFile(this.file, "r");

        // BufferManager bufferManager = BufferLocator.getBufferManager();

        //raf.setLength(rows*columns*bufferManager.getDataTypeSize(dataType));

    }

    @Override

    public void load(Buffer buffer, int row, int rows, int dataType) throws IOException {

        long pos = row*this.columns + this.startpos;

        raf.seek(pos);

        BufferManager bufferManager = BufferLocator.getBufferManager();

        int dataTypeSize = bufferManager.getDataTypeSize(dataType);

        int elements = buffer.capacity();

        ByteBuffer byteBuffer = ByteBuffer.allocate(elements * dataTypeSize);

        byteBuffer.order(this.byteOrder);

        raf.read(byteBuffer.array());

        buffer.rewind();

        byteBuffer.rewind();

        switch (dataType) {

        case BufferManager.TYPE_BYTE:

            ((ByteBuffer) buffer).put(byteBuffer);

            break;

        case BufferManager.TYPE_SHORT:

        case BufferManager.TYPE_USHORT:

            for( int element =0 ; element<elements ; element++ ) {

                ((ShortBuffer) buffer).put(byteBuffer.getShort());

            }

            break;

        case BufferManager.TYPE_INT:

            for( int element =0 ; element<elements ; element++ ) {

                ((IntBuffer) buffer).put(byteBuffer.getInt());

            }

            break;

        case BufferManager.TYPE_FLOAT:

            for( int element=0 ; element<elements ; element++ ) {

                ((FloatBuffer) buffer).put(byteBuffer.getFloat());

            }

            break;

        case BufferManager.TYPE_DOUBLE:

            for( int element=0 ; element<elements ; element++ ) {

                ((DoubleBuffer) buffer).put(byteBuffer.getDouble());

            }

            break;

        default:

            throw new IllegalArgumentException("Data Type " + dataType + " not supported.");

        }

    }

    @Override

    public void save(Buffer buffer, int row, int rows, int dataType) throws IOException {

    }

    @Override

    public boolean isSupportedSave() {

        return false;

    }

    @Override

    public BandInfo getBandInfo() {

        return null;

    }

    @Override

    protected void doDispose() throws BaseException {

        IOUtils.closeQuietly(this.raf);

        this.raf = null;

    }

}