com.cloudera.crunch.type.writable.WritableType.java Source code

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Here is the source code for com.cloudera.crunch.type.writable.WritableType.java

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/**
 * Copyright (c) 2011, Cloudera, Inc. All Rights Reserved.
 *
 * Cloudera, Inc. 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
 *
 * This software 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.cloudera.crunch.type.writable;

import java.util.List;

import org.apache.commons.lang.builder.HashCodeBuilder;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;

import com.cloudera.crunch.MapFn;
import com.cloudera.crunch.SourceTarget;
import com.cloudera.crunch.io.seq.SeqFileSourceTarget;
import com.cloudera.crunch.type.Converter;
import com.cloudera.crunch.type.DataBridge;
import com.cloudera.crunch.type.PType;
import com.cloudera.crunch.type.PTypeFamily;
import com.google.common.collect.ImmutableList;

public class WritableType<T, W> implements PType<T> {

    private final Class<T> typeClass;
    private final Class<W> writableClass;
    private final Converter converter;
    private final MapFn<W, T> inputFn;
    private final MapFn<T, W> outputFn;
    private final List<PType> subTypes;

    WritableType(Class<T> typeClass, Class<W> writableClass, MapFn<W, T> inputDoFn, MapFn<T, W> outputDoFn,
            PType... subTypes) {
        this.typeClass = typeClass;
        this.writableClass = writableClass;
        this.inputFn = inputDoFn;
        this.outputFn = outputDoFn;
        this.converter = new WritableValueConverter(writableClass);
        this.subTypes = ImmutableList.<PType>builder().add(subTypes).build();
    }

    @Override
    public PTypeFamily getFamily() {
        return WritableTypeFamily.getInstance();
    }

    @Override
    public Class<T> getTypeClass() {
        return typeClass;
    }

    @Override
    public Converter getConverter() {
        return converter;
    }

    @Override
    public MapFn getInputMapFn() {
        return inputFn;
    }

    @Override
    public MapFn getOutputMapFn() {
        return outputFn;
    }

    @Override
    public List<PType> getSubTypes() {
        return subTypes;
    }

    public Class<W> getSerializationClass() {
        return writableClass;
    }

    @Override
    public SourceTarget<T> getDefaultFileSource(Path path) {
        return new SeqFileSourceTarget<T>(path, this);
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null || !(obj instanceof WritableType)) {
            return false;
        }
        WritableType wt = (WritableType) obj;
        return (typeClass.equals(wt.typeClass) && writableClass.equals(wt.writableClass)
                && subTypes.equals(wt.subTypes));
    }

    @Override
    public int hashCode() {
        HashCodeBuilder hcb = new HashCodeBuilder();
        hcb.append(typeClass).append(writableClass).append(subTypes);
        return hcb.toHashCode();
    }
}