Package com.norconex.commons.lang.io

Class CachedOutputStream

java.lang.Object

java.io.OutputStream

com.norconex.commons.lang.io.CachedOutputStream

All Implemented Interfaces:

CachedStream, Closeable, Flushable, AutoCloseable

public class CachedOutputStream
extends OutputStream
implements CachedStream

OutputStream wrapper that caches the output so it can be retrieved once as a CachedInputStream. Invoking getInputStream() effectively close() this stream and it can no longer be written to. Obtaining an input stream before or instead of calling the close method will not delete the cache content, but rather pass the reference to it to the CachedInputStream.

To create new instances of CachedOutputStream, use the CachedStreamFactory class. Reusing the same factory will ensure all CachedOutputStream instances created share the same combined maximum memory. Invoking one of the newOutputStream(...) methods on this class have the same effect.

The internal cache stores written bytes into memory, up to to the specified maximum cache size. If content exceeds the cache limit, the cache transforms itself into a file-based cache of unlimited size. Default memory cache size is 128 KB.

Since:

1.5

See Also:

• CachedStreamFactory

Method Summary

Modifier and Type	Method	Description
void	close()
void	dispose()	Clear the cache attached to this output stream.
void	flush()
final Path	getCacheDirectory()	Gets the cache directory where temporary cache files are created.
CachedInputStream	getInputStream()	Return the cached content of the of this output stream as an input stream, before disposing it.
long	getMemCacheSize()	Get the amount of bytes used for caching this stream.
CachedStreamFactory	getStreamFactory()
boolean	isCacheEmpty()	Returns true if was nothing to cache (no writing was performed) or if the stream was closed.
CachedOutputStream	newOuputStream()
CachedOutputStream	newOuputStream(OutputStream os)
void	write(byte[] b, int off, int len)
void	write(int b)

Methods inherited from class java.io.OutputStream

nullOutputStream, write

Methods inherited from class java.lang.Object

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

Method Details

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b,
 int off,
 int len)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

getInputStream

public CachedInputStream getInputStream()
                                 throws IOException

Return the cached content of the of this output stream as an input stream, before disposing it.

Returns:

cached input stream

Throws:

IOException - problem getting input stream

dispose

public void dispose()
             throws IOException

Clear the cache attached to this output stream.

Throws:

IOException - could not dispose

Since:

3.0.0

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException

getCacheDirectory

public final Path getCacheDirectory()

Gets the cache directory where temporary cache files are created.

Specified by:

getCacheDirectory in interface CachedStream

Returns:

the cache directory

getStreamFactory

public CachedStreamFactory getStreamFactory()

isCacheEmpty

public boolean isCacheEmpty()

Returns true if was nothing to cache (no writing was performed) or if the stream was closed.

Returns:

true if empty

newOuputStream

public CachedOutputStream newOuputStream(OutputStream os)

newOuputStream

public CachedOutputStream newOuputStream()

getMemCacheSize

public long getMemCacheSize()

Description copied from interface: CachedStream

Get the amount of bytes used for caching this stream.

Specified by:

getMemCacheSize in interface CachedStream

Returns:

amount of bytes