org.apache.hadoop.hbase.io.CellOutputStream Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.hadoop.hbase.io;
import java.io.IOException;
import org.apache.hadoop.hbase.Cell;
import org.apache.yetus.audience.InterfaceAudience;
import org.apache.yetus.audience.InterfaceStability;
/**
* Accepts a stream of Cells. This can be used to build a block of cells during compactions and
* flushes, or to build a byte[] to send to the client. This could be backed by a
* List<KeyValue>, but more efficient implementations will append results to a byte[] to
* eliminate overhead, and possibly encode the cells further.
*
* To read Cells, use {@link org.apache.hadoop.hbase.CellScanner}
* @see org.apache.hadoop.hbase.CellScanner
*/
@InterfaceAudience.Private
@InterfaceStability.Evolving
public interface CellOutputStream {
/**
* Implementation must copy the entire state of the Cell. If the written Cell is modified
* immediately after the write method returns, the modifications must have absolutely no effect on
* the copy of the Cell that was added in the write.
* @param cell Cell to write out n
*/
void write(Cell cell) throws IOException;
/**
* Let the implementation decide what to do. Usually means writing accumulated data into a byte[]
* that can then be read from the implementation to be sent to disk, put in the block cache, or
* sent over the network. n
*/
void flush() throws IOException;
}