com.datatorrent.demos.ads.HdfsHashMapOutputOperator.java Source code

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Here is the source code for com.datatorrent.demos.ads.HdfsHashMapOutputOperator.java

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/*
 * Copyright (c) 2014 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.demos.ads;

import java.util.HashMap;
import java.util.Map;

import org.apache.commons.lang.text.StrSubstitutor;
import org.apache.hadoop.fs.Path;

import com.datatorrent.api.Context.OperatorContext;
import com.datatorrent.lib.io.fs.AbstractHdfsOutputOperator;

/**
 * Adapter for writing HashMap to HDFS
 * <p>
 * Serializes tuples into a HDFS file.<br/>
 * </p>
 *
 * @since 0.9.4
 */
public class HdfsHashMapOutputOperator extends AbstractHdfsOutputOperator<HashMap<Object, Object>> {

    /**
     * File name substitution parameter: The logical id assigned to the operator when assembling the DAG.
     */
    public static final String FNAME_SUB_OPERATOR_ID = "operatorId";
    /**
     * File name substitution parameter: Index of part file when a file size limit is specified.
     */
    public static final String FNAME_SUB_PART_INDEX = "partIndex";

    private int operatorId;
    private int index = 0;

    @Override
    public Path nextFilePath() {
        Map<String, String> params = new HashMap<String, String>();
        params.put(FNAME_SUB_PART_INDEX, String.valueOf(index));
        params.put(FNAME_SUB_OPERATOR_ID, Integer.toString(operatorId));
        StrSubstitutor sub = new StrSubstitutor(params, "%(", ")");
        index++;
        return new Path(sub.replace(getFilePathPattern().toString()));
    }

    @Override
    public void setup(OperatorContext context) {
        operatorId = context.getId();
        super.setup(context);
    }

    @Override
    public byte[] getBytesForTuple(HashMap<Object, Object> t) {
        return t.toString().getBytes();
    }

}