org.gpfvic.mahout.cf.taste.hadoop.item.VectorOrPrefWritable.java Source code

Introduction

Here is the source code for org.gpfvic.mahout.cf.taste.hadoop.item.VectorOrPrefWritable.java

Source

/**
 * 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.gpfvic.mahout.cf.taste.hadoop.item;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

import org.apache.hadoop.io.Writable;
import org.apache.mahout.math.Varint;
import org.apache.mahout.math.Vector;
import org.apache.mahout.math.VectorWritable;

public final class VectorOrPrefWritable implements Writable {

    private Vector vector;
    private long userID;
    private float value;

    public VectorOrPrefWritable() {
    }

    public VectorOrPrefWritable(Vector vector) {
        this.vector = vector;
    }

    public VectorOrPrefWritable(long userID, float value) {
        this.userID = userID;
        this.value = value;
    }

    public Vector getVector() {
        return vector;
    }

    public long getUserID() {
        return userID;
    }

    public float getValue() {
        return value;
    }

    void set(Vector vector) {
        this.vector = vector;
        this.userID = Long.MIN_VALUE;
        this.value = Float.NaN;
    }

    public void set(long userID, float value) {
        this.vector = null;
        this.userID = userID;
        this.value = value;
    }

    @Override
    public void write(DataOutput out) throws IOException {
        if (vector == null) {
            out.writeBoolean(false);
            Varint.writeSignedVarLong(userID, out);
            out.writeFloat(value);
        } else {
            out.writeBoolean(true);
            VectorWritable vw = new VectorWritable(vector);
            vw.setWritesLaxPrecision(true);
            vw.write(out);
        }
    }

    @Override
    public void readFields(DataInput in) throws IOException {
        boolean hasVector = in.readBoolean();
        if (hasVector) {
            VectorWritable writable = new VectorWritable();
            writable.readFields(in);
            set(writable.get());
        } else {
            long theUserID = Varint.readSignedVarLong(in);
            float theValue = in.readFloat();
            set(theUserID, theValue);
        }
    }

    @Override
    public String toString() {
        return vector == null ? userID + ":" + value : vector.toString();
    }
}