/*
* Copyright (C)2009 - SSHJ Contributors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.schmizz.sshj.transport.compression;
import net.schmizz.sshj.common.Buffer;
import net.schmizz.sshj.transport.TransportException;
/** Interface used to compress the stream of data between the SSH server and clients. */
public interface Compression {
/** Enum identifying if this object will be used to compress or uncompress data. */
enum Mode {
INFLATE,
DEFLATE
}
/**
* Initialize this object to either compress or uncompress data. This method must be called prior to any calls to
* either <code>compress</code> or <code>uncompress</code>. Once the object has been initialized, only one of
* <code>compress</code> or <code>uncompress</code> method can be called.
*
* @param mode
*/
void init(Mode mode);
/**
* Delayed compression is an Open-SSH specific feature which informs both the client and server to not compress data
* before the session has been authenticated.
*
* @return if the compression is delayed after authentication or not
*/
boolean isDelayed();
/**
* Compress the given buffer in place.
*
* @param buffer the buffer containing the data to compress s
*/
void compress(Buffer buffer);
/**
* Uncompress the data in a buffer into another buffer.
*
* @param from the buffer containing the data to uncompress
* @param to the buffer receiving the uncompressed data
*
* @throws TransportException
*/
void uncompress(Buffer from, Buffer to)
throws TransportException;
}