com.datatorrent.lib.io.fs.AbstractHDFSInputOperator.java Source code

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Here is the source code for com.datatorrent.lib.io.fs.AbstractHDFSInputOperator.java

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/*
 * Copyright (c) 2013 DataTorrent, Inc. ALL Rights Reserved.
 *
 * Licensed 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 com.datatorrent.lib.io.fs;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import com.datatorrent.api.Context.OperatorContext;

/**
 * Input Adapter for reading from HDFS File
 *
 * @since 0.3.2
 */
public abstract class AbstractHDFSInputOperator extends AbstractFileInputOperator<FSDataInputStream> {
    @Override
    public FSDataInputStream openFile(String filePath) {
        try {
            return fs.open(new Path(filePath));
        } catch (IOException ex) {
            throw new RuntimeException(ex);
        }
    }

    @Override
    public void beginWindow(long windowId) {
    }

    @Override
    public void setup(OperatorContext context) {
        try {
            fs = FileSystem.newInstance(new Configuration());
        } catch (IOException ex) {
            throw new RuntimeException(ex);
        }
    }

    @Override
    public void teardown() {
        if (fs != null) {
            try {
                fs.close();
                fs = null;
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }

    @Override
    public long getFilePointer(FSDataInputStream stream) {
        try {
            return stream.getPos();
        } catch (IOException ex) {
            throw new RuntimeException(ex.getCause());
        }
    }

    @Override
    public void seek(FSDataInputStream stream, long pos) {
        try {
            stream.seek(pos);
        } catch (IOException ex) {
            throw new RuntimeException(ex.getCause());
        }
    }

    private transient FileSystem fs;
}