org.apache.poi.poifs.filesystem
Class NPOIFSStream

java.lang.Object
  org.apache.poi.poifs.filesystem.NPOIFSStream

All Implemented Interfaces:

java.lang.Iterable<java.nio.ByteBuffer>

public class NPOIFSStream
extends java.lang.Object
implements java.lang.Iterable<java.nio.ByteBuffer>

This handles reading and writing a stream within a NPOIFSFileSystem. It can supply an iterator to read blocks, and way to write out to existing and new blocks. Most users will want a higher level version of this, which deals with properties to track which stream this is. This only works on big block streams, it doesn't handle small block ones. This uses the new NIO code TODO Implement a streaming write method, and append

Nested Class Summary

protected class

NPOIFSStream.StreamBlockByteBufferIterator Class that handles a streaming read of one stream

Constructor Summary

NPOIFSStream(BlockStore blockStore)
Constructor for a new stream.

NPOIFSStream(BlockStore blockStore, int startBlock)
Constructor for an existing stream.

Method Summary

void	free() Frees all blocks in the stream
java.util.Iterator<java.nio.ByteBuffer>	getBlockIterator()
int	getStartBlock() What block does this stream start at? Will be POIFSConstants.END_OF_CHAIN for a new stream that hasn't been written to yet.
java.util.Iterator<java.nio.ByteBuffer>	iterator() Returns an iterator that'll supply one ByteBuffer per block in the stream.
void	updateContents(byte[] contents) Updates the contents of the stream to the new set of bytes.

Methods inherited from class java.lang.Object

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

Constructor Detail

NPOIFSStream

public NPOIFSStream(BlockStore blockStore,
                    int startBlock)

Constructor for an existing stream. It's up to you to know how to get the start block (eg from a HeaderBlock or a Property)

NPOIFSStream

public NPOIFSStream(BlockStore blockStore)

Constructor for a new stream. A start block won't be allocated until you begin writing to it.

Method Detail

getStartBlock

public int getStartBlock()

What block does this stream start at? Will be POIFSConstants.END_OF_CHAIN for a new stream that hasn't been written to yet.

iterator

public java.util.Iterator<java.nio.ByteBuffer> iterator()

Returns an iterator that'll supply one ByteBuffer per block in the stream.

Specified by:

iterator in interface java.lang.Iterable<java.nio.ByteBuffer>

getBlockIterator

public java.util.Iterator<java.nio.ByteBuffer> getBlockIterator()

updateContents

public void updateContents(byte[] contents)
                    throws java.io.IOException

Updates the contents of the stream to the new set of bytes. Note - if this is property based, you'll still need to update the size in the property yourself

Throws:

java.io.IOException

free

public void free()
          throws java.io.IOException

Frees all blocks in the stream

Throws:

java.io.IOException