* @return raf of uncompressed file
* @throws IOException on read error
*/
private RandomAccessFile uncompress(RandomAccessFile inputRaf, String ufilename) throws IOException {
RandomAccessFile outputRaf = new RandomAccessFile(ufilename, "rw");
FileLock lock = null;
while (true) { // loop waiting for the lock
try {
lock = outputRaf.getRandomAccessFile().getChannel().lock(0, 1, false);
break;
} catch (OverlappingFileLockException oe) { // not sure why lock() doesnt block
try {
Thread.sleep(100); // msecs
} catch (InterruptedException e1) {
}
}
}
try {
inputRaf.seek(0);
byte[] header = new byte[Level2Record.FILE_HEADER_SIZE];
inputRaf.read(header);
outputRaf.write(header);
boolean eof = false;
int numCompBytes;
byte[] ubuff = new byte[40000];
byte[] obuff = new byte[40000];
try {
CBZip2InputStream cbzip2 = new CBZip2InputStream();
while (!eof) {
try {
numCompBytes = inputRaf.readInt();
if (numCompBytes == -1) {
if (log.isDebugEnabled()) log.debug(" done: numCompBytes=-1 ");
break;
}
} catch (EOFException ee) {
log.warn(" got EOFException ");
break; // assume this is ok
}
if (log.isDebugEnabled()) {
log.debug("reading compressed bytes " + numCompBytes + " input starts at " + inputRaf.getFilePointer() + "; output starts at " + outputRaf.getFilePointer());
}
/*
* For some stupid reason, the last block seems to
* have the number of bytes negated. So, we just
* assume that any negative number (other than -1)
* is the last block and go on our merry little way.
*/
if (numCompBytes < 0) {
if (log.isDebugEnabled()) log.debug("last block?" + numCompBytes);
numCompBytes = -numCompBytes;
eof = true;
}
byte[] buf = new byte[numCompBytes];
inputRaf.readFully(buf);
ByteArrayInputStream bis = new ByteArrayInputStream(buf, 2, numCompBytes - 2);
//CBZip2InputStream cbzip2 = new CBZip2InputStream(bis);
cbzip2.setStream(bis);
int total = 0;
int nread;
/*
while ((nread = cbzip2.read(ubuff)) != -1) {
dout2.write(ubuff, 0, nread);
total += nread;
}
*/
try {
while ((nread = cbzip2.read(ubuff)) != -1) {
if (total + nread > obuff.length) {
byte[] temp = obuff;
obuff = new byte[temp.length * 2];
System.arraycopy(temp, 0, obuff, 0, temp.length);
}
System.arraycopy(ubuff, 0, obuff, total, nread);
total += nread;
}
if (obuff.length >= 0) outputRaf.write(obuff, 0, total);
} catch (BZip2ReadException ioe) {
log.warn("Nexrad2IOSP.uncompress ", ioe);
}
float nrecords = (float) (total / 2432.0);
if (log.isDebugEnabled())
log.debug(" unpacked " + total + " num bytes " + nrecords + " records; ouput ends at " + outputRaf.getFilePointer());
}
} catch (Exception e) {
if (outputRaf != null) outputRaf.close();
outputRaf = null;
// dont leave bad files around
File ufile = new File(ufilename);
if (ufile.exists()) {
if (!ufile.delete())
log.warn("failed to delete uncompressed file (IOException)" + ufilename);
}
if (e instanceof IOException)
throw (IOException) e;
else
throw new RuntimeException(e);
}
} finally {
if (null != outputRaf) outputRaf.flush();
if (lock != null) lock.release();
}
return outputRaf;
}