org.apache.sqoop.io.SplittableBufferedWriter.java Source code

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Here is the source code for org.apache.sqoop.io.SplittableBufferedWriter.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.sqoop.io;

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * A BufferedWriter implementation that wraps around a SplittingOutputStream
 * and allows splitting of the underlying stream.
 * Splits occur at allowSplit() calls, or newLine() calls.
 */
public class SplittableBufferedWriter extends BufferedWriter {

    public static final Log LOG = LogFactory.getLog(SplittableBufferedWriter.class.getName());

    private SplittingOutputStream splitOutputStream;
    private boolean alwaysFlush;

    public SplittableBufferedWriter(final SplittingOutputStream splitOutputStream) {
        super(new OutputStreamWriter(splitOutputStream));

        this.splitOutputStream = splitOutputStream;
        this.alwaysFlush = false;
    }

    /** For testing. */
    protected SplittableBufferedWriter(final SplittingOutputStream splitOutputStream, final boolean alwaysFlush) {
        super(new OutputStreamWriter(splitOutputStream));

        this.splitOutputStream = splitOutputStream;
        this.alwaysFlush = alwaysFlush;
    }

    public void newLine() throws IOException {
        super.newLine();
        this.allowSplit();
    }

    public void allowSplit() throws IOException {
        if (alwaysFlush) {
            this.flush();
        }
        if (this.splitOutputStream.wouldSplit()) {
            LOG.debug("Starting new split");
            this.flush();
            this.splitOutputStream.allowSplit();
        }
    }
}