org.apache.hadoop.fs.s3.S3OutputStream.java Source code

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Here is the source code for org.apache.hadoop.fs.s3.S3OutputStream.java

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/**
 * 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.fs.s3;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.s3.INode.FileType;
import org.apache.hadoop.util.Progressable;

@InterfaceAudience.Private
@InterfaceStability.Unstable
@Deprecated
class S3OutputStream extends OutputStream {

    private Configuration conf;

    private int bufferSize;

    private FileSystemStore store;

    private Path path;

    private long blockSize;

    private File backupFile;

    private OutputStream backupStream;

    private Random r = new Random();

    private boolean closed;

    private int pos = 0;

    private long filePos = 0;

    private int bytesWrittenToBlock = 0;

    private byte[] outBuf;

    private List<Block> blocks = new ArrayList<Block>();

    private Block nextBlock;

    private static final Log LOG = LogFactory.getLog(S3OutputStream.class.getName());

    public S3OutputStream(Configuration conf, FileSystemStore store, Path path, long blockSize,
            Progressable progress, int buffersize) throws IOException {

        this.conf = conf;
        this.store = store;
        this.path = path;
        this.blockSize = blockSize;
        this.backupFile = newBackupFile();
        this.backupStream = new FileOutputStream(backupFile);
        this.bufferSize = buffersize;
        this.outBuf = new byte[bufferSize];

    }

    private File newBackupFile() throws IOException {
        File dir = new File(conf.get("fs.s3.buffer.dir"));
        if (!dir.exists() && !dir.mkdirs()) {
            throw new IOException("Cannot create S3 buffer directory: " + dir);
        }
        File result = File.createTempFile("output-", ".tmp", dir);
        result.deleteOnExit();
        return result;
    }

    public long getPos() throws IOException {
        return filePos;
    }

    @Override
    public synchronized void write(int b) throws IOException {
        if (closed) {
            throw new IOException("Stream closed");
        }

        if ((bytesWrittenToBlock + pos == blockSize) || (pos >= bufferSize)) {
            flush();
        }
        outBuf[pos++] = (byte) b;
        filePos++;
    }

    @Override
    public synchronized void write(byte b[], int off, int len) throws IOException {
        if (closed) {
            throw new IOException("Stream closed");
        }
        while (len > 0) {
            int remaining = bufferSize - pos;
            int toWrite = Math.min(remaining, len);
            System.arraycopy(b, off, outBuf, pos, toWrite);
            pos += toWrite;
            off += toWrite;
            len -= toWrite;
            filePos += toWrite;

            if ((bytesWrittenToBlock + pos >= blockSize) || (pos == bufferSize)) {
                flush();
            }
        }
    }

    @Override
    public synchronized void flush() throws IOException {
        if (closed) {
            throw new IOException("Stream closed");
        }

        if (bytesWrittenToBlock + pos >= blockSize) {
            flushData((int) blockSize - bytesWrittenToBlock);
        }
        if (bytesWrittenToBlock == blockSize) {
            endBlock();
        }
        flushData(pos);
    }

    private synchronized void flushData(int maxPos) throws IOException {
        int workingPos = Math.min(pos, maxPos);

        if (workingPos > 0) {
            //
            // To the local block backup, write just the bytes
            //
            backupStream.write(outBuf, 0, workingPos);

            //
            // Track position
            //
            bytesWrittenToBlock += workingPos;
            System.arraycopy(outBuf, workingPos, outBuf, 0, pos - workingPos);
            pos -= workingPos;
        }
    }

    private synchronized void endBlock() throws IOException {
        //
        // Done with local copy
        //
        backupStream.close();

        //
        // Send it to S3
        //
        // TODO: Use passed in Progressable to report progress.
        nextBlockOutputStream();
        store.storeBlock(nextBlock, backupFile);
        internalClose();

        //
        // Delete local backup, start new one
        //
        boolean b = backupFile.delete();
        if (!b) {
            LOG.warn("Ignoring failed delete");
        }
        backupFile = newBackupFile();
        backupStream = new FileOutputStream(backupFile);
        bytesWrittenToBlock = 0;
    }

    private synchronized void nextBlockOutputStream() throws IOException {
        long blockId = r.nextLong();
        while (store.blockExists(blockId)) {
            blockId = r.nextLong();
        }
        nextBlock = new Block(blockId, bytesWrittenToBlock);
        blocks.add(nextBlock);
        bytesWrittenToBlock = 0;
    }

    private synchronized void internalClose() throws IOException {
        INode inode = new INode(FileType.FILE, blocks.toArray(new Block[blocks.size()]));
        store.storeINode(path, inode);
    }

    @Override
    public synchronized void close() throws IOException {
        if (closed) {
            return;
        }

        flush();
        if (filePos == 0 || bytesWrittenToBlock != 0) {
            endBlock();
        }

        backupStream.close();
        boolean b = backupFile.delete();
        if (!b) {
            LOG.warn("Ignoring failed delete");
        }

        super.close();

        closed = true;
    }

}