cascading.tap.hadoop.DistCacheTap.java Source code

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Here is the source code for cascading.tap.hadoop.DistCacheTap.java

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/*
 * Copyright (c) 2007-2015 Concurrent, Inc. All Rights Reserved.
 *
 * Project and contact information: http://www.cascading.org/
 *
 * This file is part of the Cascading project.
 *
 * 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 cascading.tap.hadoop;

import java.io.IOException;
import java.net.URI;
import java.util.ArrayList;
import java.util.Collection;

import cascading.flow.FlowProcess;
import cascading.tap.Tap;
import cascading.tap.TapException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.RecordReader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 *
 */
public class DistCacheTap extends BaseDistCacheTap {
    private static final Logger LOG = LoggerFactory.getLogger(DistCacheTap.class);

    public static final String CASCADING_LOCAL_RESOURCES = "cascading.resources.local.";
    public static final String CASCADING_REMOTE_RESOURCES = "cascading.resources.remote.";

    public DistCacheTap(Tap<Configuration, RecordReader, OutputCollector> original) {
        super(original);
    }

    @Override
    protected Path[] getLocalCacheFiles(FlowProcess<? extends Configuration> flowProcess) throws IOException {
        String key = CASCADING_REMOTE_RESOURCES + Tap.id(this);
        String property = flowProcess.getStringProperty(key);

        if (property == null)
            throw new TapException("unable to find local resources property for: " + key);

        String[] split = property.split(",");
        Path[] paths = new Path[split.length];

        for (int i = 0; i < split.length; i++)
            paths[i] = new Path(split[i]);

        return paths;
    }

    @Override
    protected void addLocalCacheFiles(Configuration conf, URI uri) {
        String key = CASCADING_LOCAL_RESOURCES + Tap.id(this);
        Collection<String> resources = conf.getStringCollection(key);

        if (resources == null)
            resources = new ArrayList<>();

        resources.add(uri.toString());

        conf.setStrings(key, resources.toArray(new String[resources.size()]));
    }
}