@Override
public T next() throws IOException {
Tuple value = tupleInput.next(this.value);
if (value != null) {
this.value = value;
long pointer = value.<Long>getField(pointerPos);
recordsInputs.seek(pointer);
return serializer.deserialize(recordsInputs);
} else {
return null;
}
}
/**
* Closes all structures and deletes all temporary files. Even in the presence of failures, this
* method will try and continue closing files and deleting temporary files.
*
* @throws IOException Thrown if an error occurred while closing/deleting the files.
*/
public void close() throws IOException {
// we go on closing and deleting files in the presence of failures.
// we remember the first exception to occur and re-throw it later
Throwable ex = null;
synchronized (this) {
if (closed) {
return;
}
closed = true;
// close the writers
if (recordsOutFile != null) {
try {
recordsOutFile.close();
recordsOutFile = null;
} catch (Throwable t) {
LOG.error("Cannot close the large records spill file.", t);
ex = ex == null ? t : ex;
}
}
if (keysOutFile != null) {
try {
keysOutFile.close();
keysOutFile = null;
} catch (Throwable t) {
LOG.error("Cannot close the large records key spill file.", t);
ex = ex == null ? t : ex;
}
}
// close the readers
if (recordsReader != null) {
try {
recordsReader.close();
recordsReader = null;
} catch (Throwable t) {
LOG.error("Cannot close the large records reader.", t);
ex = ex == null ? t : ex;
}
}
if (keysReader != null) {
try {
keysReader.close();
keysReader = null;
} catch (Throwable t) {
LOG.error("Cannot close the large records key reader.", t);
ex = ex == null ? t : ex;
}
}
// delete the spill files
if (recordsChannel != null) {
try {
ioManager.deleteChannel(recordsChannel);
recordsChannel = null;
} catch (Throwable t) {
LOG.error("Cannot delete the large records spill file.", t);
ex = ex == null ? t : ex;
}
}
if (keysChannel != null) {
try {
ioManager.deleteChannel(keysChannel);
keysChannel = null;
} catch (Throwable t) {
LOG.error("Cannot delete the large records key spill file.", t);
ex = ex == null ? t : ex;
}
}
// close the key sorter
if (keySorter != null) {
try {
keySorter.close();
keySorter = null;
} catch (Throwable t) {
LOG.error("Cannot properly dispose the key sorter and clean up its temporary files.", t);
ex = ex == null ? t : ex;
}
}
memManager.release(memory);
recordCounter = 0;
}
// re-throw the exception, if necessary
if (ex != null) {
throw new IOException(
"An error occurred cleaning up spill files in the large record handler.", ex);
}
}