org.pentaho.di.core.compress

Interface CompressionProvider

All Known Implementing Classes:

GZIPCompressionProvider, HadoopSnappyCompressionProvider, NoneCompressionProvider, SnappyCompressionProvider, ZIPCompressionProvider

public interface CompressionProvider

The CompressionProvider interface specifies the operations needed to interact with a stream whose data is compressed on output and decompressed on input.

Method Summary

Modifier and Type	Method and Description
CompressionInputStream	createInputStream(InputStream in) Creates an input stream that decompresses data (according to the provider's implementation)
CompressionOutputStream	createOutputStream(OutputStream out) Creates an output stream that compresses data (according to the provider's implementation)
String	getDefaultExtension() Gets the default file extension for this provider.
String	getDescription() Gets the name of this provider.
String	getName() Gets the name of this provider.
boolean	supportsInput() Whether this compression provider supports input streams
boolean	supportsOutput() Whether this compression provider supports output streams

Method Detail

createInputStream

CompressionInputStream createInputStream(InputStream in)
                                  throws IOException

Creates an input stream that decompresses data (according to the provider's implementation)

Parameters:

in - An existing input stream to wrap

Returns:

a CompressionInputStream object that decompresses incoming data

Throws:

IOException

supportsInput

boolean supportsInput()

Whether this compression provider supports input streams

Returns:

true if the provider supports input streams, false otherwise

createOutputStream

CompressionOutputStream createOutputStream(OutputStream out)
                                    throws IOException

Creates an output stream that compresses data (according to the provider's implementation)

Parameters:

out - An existing output stream to wrap

Returns:

a CompressionOutputStream object that compresses outgoing data

Throws:

IOException

supportsOutput

boolean supportsOutput()

Whether this compression provider supports output streams

Returns:

true if the provider supports output streams, false otherwise

getName

String getName()

Gets the name of this provider. Used for display and as a reference in saved artifacts (transformations, e.g.)

Returns:

A String containing the name of this provider

getDescription

String getDescription()

Gets the name of this provider. Used for display e.g.

Returns:

A String containing a description of this provider

getDefaultExtension

String getDefaultExtension()

Gets the default file extension for this provider. If the streams are wrapped in File streams, this method can be used to determine an appropriate extension to append to the filename so the file will be recognized as an artifact of the compression mechanism (.zip, .bz2, e.g.)

Returns:

A String containing the default file extension for this provider