com.ikanow.aleph2.analytics.r.assets.Aleph2MultiInputSplit.java Source code

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Here is the source code for com.ikanow.aleph2.analytics.r.assets.Aleph2MultiInputSplit.java

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/*******************************************************************************
 * Copyright 2015, The IKANOW Open Source 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 com.ikanow.aleph2.analytics.r.assets;

import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.Optional;

import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.serializer.Deserializer;
import org.apache.hadoop.io.serializer.SerializationFactory;
import org.apache.hadoop.io.serializer.Serializer;
import org.apache.hadoop.mapreduce.InputFormat;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.util.ReflectionUtils;

/** Encapsulates another input format class
 * @author Alex
 */
@SuppressWarnings("rawtypes")
public class Aleph2MultiInputSplit extends InputSplit implements Configurable, Writable {

    protected String _name;
    protected InputSplit _delegate;
    protected Class<? extends InputSplit> _input_split;
    protected Class<? extends InputFormat> _input_format;
    protected Class<? extends Mapper> _mapper;

    protected Configuration _conf;

    public InputSplit getInputSplit() {
        return _delegate;
    }

    public Class<? extends InputFormat> getInputFormatClass() {
        return _input_format;
    }

    public Class<? extends Mapper> getMapperClass() {
        return _mapper;
    }

    public String getName() {
        return _name;
    }

    public Aleph2MultiInputSplit() {
    }

    public Aleph2MultiInputSplit(String name, InputSplit delegate, Configuration config,
            Class<? extends InputFormat> input_format, Class<? extends Mapper> mapper_delegate) {
        _name = name;
        _delegate = delegate;
        _conf = config;
        _input_split = delegate.getClass();
        _input_format = input_format;
        _mapper = mapper_delegate;
    }

    @SuppressWarnings("unchecked")
    @Override
    public void readFields(DataInput in) throws IOException {
        _name = Text.readString(in);
        _input_split = (Class<? extends InputSplit>) readClass(in);
        _input_format = (Class<? extends InputFormat<?, ?>>) readClass(in);
        _mapper = (Class<? extends Mapper<?, ?, ?, ?>>) readClass(in);
        _delegate = (InputSplit) ReflectionUtils.newInstance(_input_split, _conf);
        final SerializationFactory factory = new SerializationFactory(_conf);
        final Deserializer deserializer = factory.getDeserializer(_input_split);
        deserializer.open((DataInputStream) in);
        _delegate = (InputSplit) deserializer.deserialize(_delegate);
    }

    private Class<?> readClass(DataInput in) throws IOException {
        String className = Text.readString(in);
        try {
            return _conf.getClassByName(className);
        } catch (ClassNotFoundException e) {
            throw new RuntimeException("readObject can't find class", e);
        }
    }

    @SuppressWarnings("unchecked")
    @Override
    public void write(DataOutput out) throws IOException {
        Text.writeString(out, _name);
        Text.writeString(out, _input_split.getName());
        Text.writeString(out, _input_format.getName());
        Text.writeString(out, _mapper.getName());
        final SerializationFactory factory = new SerializationFactory(_conf);
        final Serializer serializer = factory.getSerializer(_input_split);
        serializer.open((DataOutputStream) out);
        serializer.serialize(_delegate);
    }

    @Override
    public Configuration getConf() {
        return _conf;
    }

    @Override
    public void setConf(Configuration conf) {
        _conf = conf;
    }

    @Override
    public long getLength() throws IOException, InterruptedException {
        return _delegate.getLength();
    }

    @Override
    public String[] getLocations() throws IOException, InterruptedException {
        return _delegate.getLocations();
    }

    @Override
    public String toString() {
        return Aleph2MultiInputSplit.class.getSimpleName() + ":" + Optional.ofNullable(_name).orElse("(no name)")
                + ":" + Optional.ofNullable(_delegate).map(d -> d.toString()).orElse("none");
    }
}