org.apache.solr.store.hdfs.HdfsFileWriter.java Source code

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Here is the source code for org.apache.solr.store.hdfs.HdfsFileWriter.java

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package org.apache.solr.store.hdfs;

/*
 * 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.
 */

import java.io.Closeable;
import java.io.IOException;
import java.util.EnumSet;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CreateFlag;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FsServerDefaults;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.lucene.store.DataOutput;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class HdfsFileWriter extends DataOutput implements Closeable {
    public static Logger LOG = LoggerFactory.getLogger(HdfsFileWriter.class);

    public static final String HDFS_SYNC_BLOCK = "solr.hdfs.sync.block";

    private final Path path;
    private FSDataOutputStream outputStream;
    private long currentPosition;

    public HdfsFileWriter(FileSystem fileSystem, Path path) throws IOException {
        LOG.debug("Creating writer on {}", path);
        this.path = path;

        Configuration conf = fileSystem.getConf();
        FsServerDefaults fsDefaults = fileSystem.getServerDefaults(path);
        EnumSet<CreateFlag> flags = EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE);
        if (Boolean.getBoolean(HDFS_SYNC_BLOCK)) {
            flags.add(CreateFlag.SYNC_BLOCK);
        }
        outputStream = fileSystem.create(path, FsPermission.getDefault().applyUMask(FsPermission.getUMask(conf)),
                flags, fsDefaults.getFileBufferSize(), fsDefaults.getReplication(), fsDefaults.getBlockSize(),
                null);
    }

    public long length() {
        return currentPosition;
    }

    public void seek(long pos) throws IOException {
        LOG.error("Invalid seek called on {}", path);
        throw new IOException("Seek not supported");
    }

    public void flush() throws IOException {
        // flush to the network, not guarantees it makes it to the DN (vs hflush)
        outputStream.flush();
        LOG.debug("Flushed file {}", path);
    }

    public void close() throws IOException {
        outputStream.close();
        LOG.debug("Closed writer on {}", path);
    }

    @Override
    public void writeByte(byte b) throws IOException {
        outputStream.write(b & 0xFF);
        currentPosition++;
    }

    @Override
    public void writeBytes(byte[] b, int offset, int length) throws IOException {
        outputStream.write(b, offset, length);
        currentPosition += length;
    }

    public long getPosition() {
        return currentPosition;
    }
}