org.apache.flink.runtime.io.disk.iomanager.BlockChannelWriter 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.flink.runtime.io.disk.iomanager;
import java.io.IOException;
import java.util.concurrent.LinkedBlockingQueue;
/**
* A writer that writes data in blocks to a file channel. The writer receives the data blocks in the form of
* {@link org.apache.flink.core.memory.MemorySegment}, which it writes entirely to the channel,
* regardless of how space in the segment is used. The writing may be realized synchronously, or asynchronously,
* depending on the implementation.
*/
public interface BlockChannelWriter extends BlockChannelWriterWithCallback {
/**
* Gets the next memory segment that has been written and is available again.
* This method blocks until such a segment is available, or until an error occurs in the writer, or the
* writer is closed.
*
* NOTE: If this method is invoked without any segment ever returning (for example, because the
* {@link #writeBlock} method has not been invoked accordingly), the method may block
* forever.
*
* @return The next memory segment from the writers's return queue.
* @throws IOException Thrown, if an I/O error occurs in the writer while waiting for the request to return.
*/
T getNextReturnedBlock() throws IOException;
/**
* Gets the queue in which the memory segments are queued after the asynchronous write
* is completed
*
* @return The queue with the written memory segments.
*/
LinkedBlockingQueue getReturnQueue();
}