alluxio.client.netty.NettyUnderFileSystemFileWriter.java Source code

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Here is the source code for alluxio.client.netty.NettyUnderFileSystemFileWriter.java

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/*
 * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
 * (the "License"). You may not use this work except in compliance with the License, which is
 * available at www.apache.org/licenses/LICENSE-2.0
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied, as more fully set forth in the License.
 *
 * See the NOTICE file distributed with this work for information regarding copyright ownership.
 */

package alluxio.client.netty;

import alluxio.Constants;
import alluxio.exception.ExceptionMessage;
import alluxio.network.protocol.RPCErrorResponse;
import alluxio.network.protocol.RPCFileWriteRequest;
import alluxio.network.protocol.RPCFileWriteResponse;
import alluxio.network.protocol.RPCMessage;
import alluxio.network.protocol.RPCResponse;
import alluxio.network.protocol.databuffer.DataByteArrayChannel;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.util.concurrent.TimeUnit;

import javax.annotation.concurrent.NotThreadSafe;

/**
 * Writer for an under file system file through a worker data server via Netty. This class does not
 * hold any state specific to the file and can be used to write to different files, but not
 * concurrently. This class does not keep lingering resources and does not need to be closed.
 */
@NotThreadSafe
public final class NettyUnderFileSystemFileWriter {
    private static final Logger LOG = LoggerFactory.getLogger(Constants.LOGGER_TYPE);

    /** Netty bootstrap for the connection. */
    private final Bootstrap mClientBootstrap;
    /** Handler for Netty messages. */
    private final ClientHandler mHandler;

    /**
     * Constructor for a Netty based writer to an under file system file on a worker.
     */
    public NettyUnderFileSystemFileWriter() {
        mHandler = new ClientHandler();
        mClientBootstrap = NettyClient.createClientBootstrap(mHandler);
    }

    /**
     * Writes data to the file in the under file system.
     *
     * @param address worker address to write the data to
     * @param ufsFileId worker file id referencing the file
     * @param fileOffset where in the file to start writing, only sequential writes are supported
     * @param bytes data to write
     * @param offset start offset of the data
     * @param length length to write
     * @throws IOException if an error occurs during the write
     */
    public void write(InetSocketAddress address, long ufsFileId, long fileOffset, byte[] bytes, int offset,
            int length) throws IOException {
        SingleResponseListener listener = null;
        try {
            ChannelFuture f = mClientBootstrap.connect(address).sync();

            LOG.debug("Connected to remote machine {}", address);
            Channel channel = f.channel();
            listener = new SingleResponseListener();
            mHandler.addListener(listener);
            channel.writeAndFlush(new RPCFileWriteRequest(ufsFileId, fileOffset, length,
                    new DataByteArrayChannel(bytes, offset, length)));

            RPCResponse response = listener.get(NettyClient.TIMEOUT_MS, TimeUnit.MILLISECONDS);
            channel.close().sync();

            switch (response.getType()) {
            case RPC_FILE_WRITE_RESPONSE:
                RPCFileWriteResponse resp = (RPCFileWriteResponse) response;
                RPCResponse.Status status = resp.getStatus();
                LOG.debug("status: {} from remote machine {} received", status, address);

                if (status != RPCResponse.Status.SUCCESS) {
                    throw new IOException(ExceptionMessage.UNDER_FILE_WRITE_ERROR.getMessage(ufsFileId, address,
                            status.getMessage()));
                }
                break;
            case RPC_ERROR_RESPONSE:
                RPCErrorResponse error = (RPCErrorResponse) response;
                throw new IOException(error.getStatus().getMessage());
            default:
                throw new IOException(ExceptionMessage.UNEXPECTED_RPC_RESPONSE.getMessage(response.getType(),
                        RPCMessage.Type.RPC_FILE_WRITE_RESPONSE));
            }
        } catch (Exception e) {
            throw new IOException(e);
        } finally {
            if (listener != null) {
                mHandler.removeListener(listener);
            }
        }
    }
}