org.apache.hadoop.tools.rumen.HistoryEventEmitter.java Source code

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Here is the source code for org.apache.hadoop.tools.rumen.HistoryEventEmitter.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.tools.rumen;

import java.text.ParseException;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.mapreduce.Counters;

abstract class HistoryEventEmitter {
    static final private Log LOG = LogFactory.getLog(HistoryEventEmitter.class);

    abstract List<SingleEventEmitter> nonFinalSEEs();

    abstract List<SingleEventEmitter> finalSEEs();

    protected HistoryEventEmitter() {
        // no code
    }

    enum PostEmitAction {
        NONE, REMOVE_HEE
    };

    final Pair<Queue<HistoryEvent>, PostEmitAction> emitterCore(ParsedLine line, String name) {
        Queue<HistoryEvent> results = new LinkedList<HistoryEvent>();
        PostEmitAction removeEmitter = PostEmitAction.NONE;
        for (SingleEventEmitter see : nonFinalSEEs()) {
            HistoryEvent event = see.maybeEmitEvent(line, name, this);
            if (event != null) {
                results.add(event);
            }
        }
        for (SingleEventEmitter see : finalSEEs()) {
            HistoryEvent event = see.maybeEmitEvent(line, name, this);
            if (event != null) {
                results.add(event);
                removeEmitter = PostEmitAction.REMOVE_HEE;
                break;
            }
        }
        return new Pair<Queue<HistoryEvent>, PostEmitAction>(results, removeEmitter);
    }

    protected static Counters maybeParseCounters(String counters) {
        try {
            return parseCounters(counters);
        } catch (ParseException e) {
            LOG.warn("The counter string, \"" + counters + "\" is badly formatted.");
            return null;
        }
    }

    protected static Counters parseCounters(String counters) throws ParseException {
        if (counters == null) {
            LOG.warn("HistoryEventEmitters: null counter detected:");
            return null;
        }

        counters = counters.replace("\\.", "\\\\.");
        counters = counters.replace("\\\\(", "\\(");
        counters = counters.replace("\\\\)", "\\)");
        counters = counters.replace("\\\\[", "\\[");
        counters = counters.replace("\\\\]", "\\]");

        org.apache.hadoop.mapred.Counters depForm = org.apache.hadoop.mapred.Counters
                .fromEscapedCompactString(counters);

        return new Counters(depForm);
    }
}