ucar.nc2.iosp.netcdf3.N3nioMMap.save Maven / Gradle / Ivy
/*
* Copyright 1998-2009 University Corporation for Atmospheric Research/Unidata
*
* Portions of this software were developed by the Unidata Program at the
* University Corporation for Atmospheric Research.
*
* Access and use of this software shall impose the following obligations
* and understandings on the user. The user is granted the right, without
* any fee or cost, to use, copy, modify, alter, enhance and distribute
* this software, and any derivative works thereof, and its supporting
* documentation for any purpose whatsoever, provided that this entire
* notice appears in all copies of the software, derivative works and
* supporting documentation. Further, UCAR requests that the user credit
* UCAR/Unidata in any publications that result from the use of this
* software or in any product that includes this software. The names UCAR
* and/or Unidata, however, may not be used in any advertising or publicity
* to endorse or promote any products or commercial entity unless specific
* written permission is obtained from UCAR/Unidata. The user also
* understands that UCAR/Unidata is not obligated to provide the user with
* any support, consulting, training or assistance of any kind with regard
* to the use, operation and performance of this software nor to provide
* the user with any updates, revisions, new versions or "bug fixes."
*
* THIS SOFTWARE IS PROVIDED BY UCAR/UNIDATA "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL UCAR/UNIDATA BE LIABLE FOR ANY SPECIAL,
* INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
* FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE ACCESS, USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package ucar.nc2.iosp.netcdf3;
import ucar.ma2.*;
import ucar.nc2.iosp.Indexer;
import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.net.URL;
import java.util.*;
/**
* Use memmory mapping to do bulk read/write.
*/
class N3nioMMap extends N3iosp {
private MappedByteBuffer source;
protected FileChannel channel;
// used for writing
private int minIncrement = 10000000; // minimum file increment size 10M
//////////////////////////////////////////////////////////////////////////////////////
// read existing file
public void open(ucar.unidata.io.RandomAccessFile raf, ucar.nc2.NetcdfFile ncfile,
ucar.nc2.util.CancelTask cancelTask) throws IOException {
super.open( raf, ncfile, cancelTask);
channel = raf.getRandomAccessFile().getChannel();
source = channel.map( readonly ? FileChannel.MapMode.READ_ONLY : FileChannel.MapMode.READ_WRITE, (long) 0, channel.size());
if (debug) System.out.println ("Opened file to read:'" + raf.getLocation()+ "', size=" + channel.size());
}
/**
* Read data subset from file for a variable, create primitive array.
* @param beginOffset: variable's beginning byte offset in file.
* @param index handles skipping around in the file.
* @param source from this buye buffer
* @param dataType dataType of the variable
* @return primitive array with data read in
*/
protected Object readData( int beginOffset, Indexer index, DataType dataType) {
int offset = 0;
int chunk = index.getChunkSize();
int size = index.getTotalSize();
if ((dataType == DataType.BYTE) || (dataType == DataType.CHAR)) {
byte[] buff = new byte[size];
while (index.hasNext()) {
source.position( beginOffset + index.next());
source.get(buff, offset, chunk);
offset += chunk;
}
return (dataType == DataType.BYTE) ? buff : (Object) convertByteToChar( buff);
} else if (dataType == DataType.SHORT) {
short[] buff = new short[size];
while (index.hasNext()) {
source.position( beginOffset + index.next());
ShortBuffer cb = source.asShortBuffer();
cb.get(buff, offset, chunk);
offset += chunk;
}
return buff;
} else if (dataType == DataType.INT) {
int[] buff = new int[size];
while (index.hasNext()) {
source.position( beginOffset + index.next());
IntBuffer cb = source.asIntBuffer();
cb.get(buff, offset, chunk);
offset += chunk;
}
return buff;
} else if (dataType == DataType.FLOAT) {
float[] buff = new float[size];
while (index.hasNext()) {
source.position( beginOffset + index.next());
FloatBuffer cb = source.asFloatBuffer();
cb.get(buff, offset, chunk);
offset += chunk;
}
return buff;
} else if (dataType == DataType.DOUBLE) {
double[] buff = new double[size];
while (index.hasNext()) {
source.position( beginOffset + index.next());
DoubleBuffer cb = source.asDoubleBuffer();
cb.get(buff, offset, chunk);
offset += chunk;
}
return buff;
}
throw new IllegalStateException();
}
public void create(String filename, ucar.nc2.NetcdfFile ncfile, boolean fill) throws IOException {
super.create( filename, ncfile, fill);
channel = raf.getChannel();
source = channel.map(FileChannel.MapMode.READ_WRITE, (long) 0, recStart);
if (debug) out.println ("Opened file to write:'" + filename+ "', size=" + channel.size());
flush();
}
protected void setNumrecs(int n) throws IOException {
if (n <= numrecs) return;
super.setNumrecs(n);
// gotta grow the mapBuffer
long need = recStart + n * recsize;
if (debugSize) System.out.println("gotta grow the mapBuffer to = "+need);
source = channel.map(FileChannel.MapMode.READ_WRITE, (long) 0, need);
}
/**
* Write data subset to file for a variable, create primitive array.
* @param beginOffset: variable's beginning byte offset in file.
* @param index handles skipping around in the file.
* @param source from this buye buffer
* @param dataType dataType of the variable
* @return primitive array with data read in
*/
protected void writeData( Array aa, int beginOffset, Indexer index, DataType dataType) {
int offset = 0;
int chunk = index.getChunkSize();
if ((dataType == DataType.BYTE) || (dataType == DataType.CHAR)) {
byte[] buff;
if (dataType == DataType.BYTE)
buff = (byte[]) aa.getStorage();
else {
char[] cbuff = (char[]) aa.getStorage();
buff = convertCharToByte( cbuff);
}
while (index.hasNext()) {
source.position( beginOffset + index.next());
source.put(buff, offset, chunk);
offset += chunk;
}
return;
} else if (dataType == DataType.SHORT) {
short[] buff = (short[]) aa.getStorage();
while (index.hasNext()) {
source.position( beginOffset + index.next());
ShortBuffer cb = source.asShortBuffer();
cb.put(buff, offset, chunk);
offset += chunk;
}
return;
} else if (dataType == DataType.INT) {
int[] buff = (int[]) aa.getStorage();
while (index.hasNext()) {
source.position( beginOffset + index.next());
IntBuffer cb = source.asIntBuffer();
cb.put(buff, offset, chunk);
offset += chunk;
}
return;
} else if (dataType == DataType.FLOAT) {
float[] buff = (float[]) aa.getStorage();
while (index.hasNext()) {
source.position( beginOffset + index.next());
FloatBuffer cb = source.asFloatBuffer();
cb.put(buff, offset, chunk);
offset += chunk;
}
return;
} else if (dataType == DataType.DOUBLE) {
double[] buff = (double[]) aa.getStorage();
while (index.hasNext()) {
source.position( beginOffset + index.next());
DoubleBuffer cb = source.asDoubleBuffer();
cb.put(buff, offset, chunk);
offset += chunk;
}
return;
}
throw new IllegalStateException();
}
public void flush() throws IOException {
channel.force( false);
}
public void close() throws IOException {
if (!readonly) flush();
if (channel != null)
channel.close();
super.close();
}
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