com.facebook.hiveio.input.HiveInputDescription.java Source code

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Here is the source code for com.facebook.hiveio.input.HiveInputDescription.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 com.facebook.hiveio.input;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hive.metastore.api.ThriftHiveMetastore;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableUtils;
import org.apache.thrift.TException;

import com.facebook.hiveio.common.HiveTableDesc;
import com.facebook.hiveio.common.MetastoreDesc;
import com.facebook.hiveio.common.Writables;
import com.google.common.base.Objects;
import com.google.common.collect.Lists;

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

/**
 * Description of hive table to read from.
 */
public class HiveInputDescription implements Writable {
    /** Metastore to use. Optional. */
    private MetastoreDesc metastoreDesc = new MetastoreDesc();
    /** Hive table */
    private HiveTableDesc tableDesc = new HiveTableDesc();
    /** Columns to read in table */
    private List<String> columns = Lists.newArrayList();
    /** Filter for which partitions to read from  */
    private String partitionFilter = "";
    /** Number of splits per matched partition desired */
    private int numSplits;

    /**
     * Get columns to read
     *
     * @return list of columns to read
     */
    public List<String> getColumns() {
        return columns;
    }

    /**
     * Add a column to read
     *
     * @param column String name of column
     * @return this
     */
    public HiveInputDescription addColumn(String column) {
        columns.add(column);
        return this;
    }

    /**
     * Set columns to read
     *
     * @param columns list of columns to read
     * @return this
     */
    public HiveInputDescription setColumns(List<String> columns) {
        this.columns = columns;
        return this;
    }

    /**
     * Check if we have columns specified
     *
     * @return true if we have columns
     */
    public boolean hasColumns() {
        return columns != null && !columns.isEmpty();
    }

    public HiveTableDesc getTableDesc() {
        return tableDesc;
    }

    public void setTableDesc(HiveTableDesc hiveTableDesc) {
        this.tableDesc = hiveTableDesc;
    }

    /**
     * Get partition filter string
     *
     * @return partition filter
     */
    public String getPartitionFilter() {
        return partitionFilter;
    }

    /**
     * Set partition filter
     *
     * @param partitionFilter HQL partition filter
     * @return this
     */
    public HiveInputDescription setPartitionFilter(String partitionFilter) {
        this.partitionFilter = partitionFilter;
        return this;
    }

    /**
     * Do we have a partition filter
     *
     * @return true if we have a partition filter
     */
    public boolean hasPartitionFilter() {
        return partitionFilter != null && !partitionFilter.isEmpty();
    }

    /**
     * Get desired number of splits
     *
     * @return number of splits
     */
    public int getNumSplits() {
        return numSplits;
    }

    /**
     * Set number of splits
     *
     * @param numSplits number of splits
     * @return this
     */
    public HiveInputDescription setNumSplits(int numSplits) {
        this.numSplits = numSplits;
        return this;
    }

    public MetastoreDesc getMetastoreDesc() {
        return metastoreDesc;
    }

    /**
     * Make metastore client
     *
     * @param conf Configuration
     * @return Thrift Metastore client
     * @throws TException
     */
    public ThriftHiveMetastore.Iface metastoreClient(Configuration conf) throws TException {
        return metastoreDesc.makeClient(conf);
    }

    @Override
    public void write(DataOutput out) throws IOException {
        metastoreDesc.write(out);
        tableDesc.write(out);
        Writables.writeStringList(out, columns);
        WritableUtils.writeString(out, partitionFilter);
        out.writeInt(numSplits);
    }

    @Override
    public void readFields(DataInput in) throws IOException {
        metastoreDesc.readFields(in);
        tableDesc.readFields(in);
        Writables.readStringList(in, columns);
        partitionFilter = WritableUtils.readString(in);
        numSplits = in.readInt();
    }

    @Override
    public String toString() {
        return Objects.toStringHelper(this).add("metastoreDesc", metastoreDesc).add("tableDesc", tableDesc)
                .add("columns", columns).add("partitionFilter", partitionFilter)
                .add("numSplits", String.valueOf(numSplits)).toString();
    }
}