com.partnersoft.io
Class DataCopier

java.lang.Object
  com.partnersoft.io.DataCopier

All Implemented Interfaces:

IOCopier

public class DataCopier
extends java.lang.Object
implements IOCopier

Copies bytes from a DataInput to a DataOutput.

Typical usage:

 input = new DataDataInput(new FileDataInput(FileLib
                .createFile("data/copyfrom.dat")));
 output = new DataDataOutput(new FileDataOutput(FileLib
                .createFile("data/copyto.dat")));
 copier = new DataCopier(input, output);
 copier.copy();
 copier.close();
 

Copyright 2006 Partner Software, Inc.

Author:

Paul Reavis

Constructor Summary

DataCopier(java.io.DataInput source, java.io.DataOutput sink)
Constructs a DataCopier for the given source and sink with standard buffer size and no specified data size.

DataCopier(java.io.DataInput source, java.io.DataOutput sink, int bufferSize)
Constructs a DataCopier for the given source and sink with the given buffer size and no specified data size.

DataCopier(java.io.DataInput source, long dataSize, java.io.DataOutput sink)
Constructs a DataCopier for the given source, data size and sink with standard buffer size.

DataCopier(java.io.DataInput source, long dataSize, java.io.DataOutput sink, int bufferSize)
Constructs a DataCopier for the given source, sink, data size, and buffer size.

Method Summary

void	close() DataInput and DataOutput do not define flushing or closing methods, so this method does nothing.
long	copy() If dataSize is set, copies that amount.
long	copy(long howMuch) Copies the specified amount of data from the source to the sink.
long	copyBlockingOnce() Block only once, copying available data, but quit as soon as a block would occur.
long	copyWithoutBlocking() Copies only available data.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DataCopier

public DataCopier(java.io.DataInput source,
                  long dataSize,
                  java.io.DataOutput sink,
                  int bufferSize)

Constructs a DataCopier for the given source, sink, data size, and buffer size. The data size is required because DataInput does not support detection of EOF the same way InputStream does. Therefore, copy() doesn't know when to stop without causing an exception. The data size can be set to java.lang.Long.MAX_VALUE if you don't plan on using copy().

DataCopier

public DataCopier(java.io.DataInput source,
                  long dataSize,
                  java.io.DataOutput sink)

Constructs a DataCopier for the given source, data size and sink with standard buffer size.

See Also:

IOConstants.BUFFER_SIZE

DataCopier

public DataCopier(java.io.DataInput source,
                  java.io.DataOutput sink,
                  int bufferSize)

Constructs a DataCopier for the given source and sink with the given buffer size and no specified data size.

DataCopier

public DataCopier(java.io.DataInput source,
                  java.io.DataOutput sink)

Constructs a DataCopier for the given source and sink with standard buffer size and no specified data size.

See Also:

IOConstants.BUFFER_SIZE

Method Detail

copy

public long copy()
          throws java.io.IOException

If dataSize is set, copies that amount. If not, this will cause an EOFException.

Specified by:

copy in interface IOCopier

Returns:

total number of items (bytes, characters, etc.) copied

Throws:

java.io.IOException - if something prevents the copy

copy

public long copy(long howMuch)
          throws java.io.IOException

Description copied from interface: IOCopier

Copies the specified amount of data from the source to the sink. Flushes the output when done but does not close either source or sink. Can be called multiple times, as long as there is available data.

Specified by:

copy in interface IOCopier

Parameters:

howMuch - how many items (bytes, characters, etc.) to copy

Returns:

total number of items (bytes, characters, etc.) copied

Throws:

java.io.IOException - if something prevents the copy or if there are not enough items to copy

copyWithoutBlocking

public long copyWithoutBlocking()
                         throws java.io.IOException

Description copied from interface: IOCopier

Copies only available data. No blocking is done; if no data is available, stop.

This method is optional, if it's not appropriate for the kind of copy, throws an UnsupportedOperationException.

Specified by:

copyWithoutBlocking in interface IOCopier

Throws:

java.io.IOException

copyBlockingOnce

public long copyBlockingOnce()
                      throws java.io.IOException

Description copied from interface: IOCopier

Block only once, copying available data, but quit as soon as a block would occur.

This method is optional, if it's not appropriate for the kind of copy, throws an UnsupportedOperationException.

Specified by:

copyBlockingOnce in interface IOCopier

Throws:

java.io.IOException

close

public void close()
           throws java.io.IOException

DataInput and DataOutput do not define flushing or closing methods, so this method does nothing.

Specified by:

close in interface IOCopier

Throws:

java.io.IOException - if anything prevents closing.