/*
* Copyright 1998-2014 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;
import ucar.ma2.Array;
import ucar.ma2.InvalidRangeException;
import ucar.ma2.Section;
import ucar.ma2.StructureDataIterator;
import ucar.nc2.NetcdfFile;
import ucar.nc2.ParsedSectionSpec;
import ucar.nc2.Structure;
import ucar.nc2.util.CancelTask;
import ucar.unidata.io.RandomAccessFile;
import ucar.unidata.util.Format;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.channels.WritableByteChannel;
import java.util.Formatter;
/**
* Abstract base class for IOSP implementations that provides default implementations
* of readToByteChannel(...) and readSection(...).
*
* <p>Implementations should make sure to handle the RandomAccessFile properly by
* doing one of the following:
*
* <ol>
* <li> Write your own open(...) and close() methods that keep track of the
* RandomAccessFile, be sure to close the RandomAccessFile in your close()
* method.</li>
* <li> Write your own open(...) and close() methods that call the open(...)
* and close() methods defined here, use the "raf" variable also defined
* here.</li>
* <li> Don't write an open(...) or close() method, so that those defined
* here are used.</li>
* </ol>
*
*/
public abstract class AbstractIOServiceProvider implements IOServiceProvider {
/**
* Subclasses that use AbstractIOServiceProvider.open(...) or .close()
* should use this (instead of their own private variable).
*/
protected ucar.unidata.io.RandomAccessFile raf;
protected String location;
protected int rafOrder = RandomAccessFile.BIG_ENDIAN;
protected NetcdfFile ncfile;
@Override
public void open( RandomAccessFile raf, NetcdfFile ncfile, CancelTask cancelTask ) throws IOException {
this.raf = raf;
this.location = (raf != null) ? raf.getLocation() : null;
this.ncfile = ncfile;
}
@Override
public void close() throws java.io.IOException {
if (raf != null)
raf.close();
raf = null;
}
// release any resources like file handles
public void release() throws IOException {
if (raf != null)
raf.close();
raf = null;
}
// reacquire any resources like file handles
public void reacquire() throws IOException {
raf = RandomAccessFile.acquire(location);
this.raf.order(rafOrder);
}
// default implementation, reads into an Array, then writes to WritableByteChannel
// subclasses should override if possible
// LOOK DataOutputStream uses big-endian
@Override
public long readToByteChannel(ucar.nc2.Variable v2, Section section, WritableByteChannel channel)
throws java.io.IOException, ucar.ma2.InvalidRangeException {
Array data = readData(v2, section);
return IospHelper.copyToByteChannel(data, channel);
}
public long readToOutputStream(ucar.nc2.Variable v2, Section section, OutputStream out)
throws java.io.IOException, ucar.ma2.InvalidRangeException {
Array data = readData(v2, section);
return IospHelper.copyToOutputStream(data, out);
}
public long streamToByteChannel(ucar.nc2.Variable v2, Section section, WritableByteChannel channel)
throws java.io.IOException, ucar.ma2.InvalidRangeException {
Array data = readData(v2, section);
return IospHelper.copyToByteChannel(data, channel);
}
@Override
public ucar.ma2.Array readSection(ParsedSectionSpec cer) throws IOException, InvalidRangeException {
return IospHelper.readSection(cer); // IOSPs can optimize by overriding
}
@Override
public StructureDataIterator getStructureIterator(Structure s, int bufferSize) throws java.io.IOException {
return null;
}
@Override
public Object sendIospMessage(Object message) {
if (message == NetcdfFile.IOSP_MESSAGE_RANDOM_ACCESS_FILE) {
return raf;
}
return null;
}
@Override
public boolean syncExtend() throws IOException {
return false;
}
/**
* Returns the time that the underlying file(s) were last modified. If they've changed since they were stored in the
* cache, they will be closed and reopened with {@link ucar.nc2.util.cache.FileFactory}.
*
* @return a {@code long} value representing the time the file(s) were last modified or {@code 0L} if the
* last-modified time couldn't be determined for any reason.
*/
public long getLastModified() {
if (location != null) {
File file = new File(location);
return file.lastModified();
} else {
return 0;
}
}
@Override
public String toStringDebug(Object o) {
return "";
}
@Override
public String getDetailInfo() {
if (raf == null) return "";
try {
Formatter fout = new Formatter();
double size = raf.length() / (1000.0 * 1000.0);
fout.format(" raf = %s%n", raf.getLocation());
fout.format(" size= %d (%s Mb)%n%n", raf.length(), Format.dfrac(size, 3));
return fout.toString();
} catch (IOException e) {
return e.getMessage();
}
}
@Override
public String getFileTypeVersion() {
return "N/A";
}
}