com.pivotal.hawq.mapreduce.parquet.HAWQParquetInputFormat.java Source code

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Here is the source code for com.pivotal.hawq.mapreduce.parquet.HAWQParquetInputFormat.java

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package com.pivotal.hawq.mapreduce.parquet;

/*
 * 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.
 */

import com.google.common.collect.Lists;
import com.pivotal.hawq.mapreduce.HAWQRecord;
import com.pivotal.hawq.mapreduce.file.HAWQFileStatus;
import com.pivotal.hawq.mapreduce.metadata.HAWQParquetTableMetadata;
import com.pivotal.hawq.mapreduce.parquet.support.HAWQReadSupport;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import parquet.hadoop.ParquetInputFormat;

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

/**
 * An InputFormat that reads input data from HAWQ Parquet table.
 */
public class HAWQParquetInputFormat extends ParquetInputFormat<HAWQRecord> {

    private static HAWQFileStatus[] hawqFileStatuses;

    public HAWQParquetInputFormat() {
        super(HAWQReadSupport.class);
    }

    public static void setInput(Configuration conf, HAWQParquetTableMetadata metadata) {
        hawqFileStatuses = metadata.getFileStatuses();
    }

    @Override
    public List<InputSplit> getSplits(JobContext jobContext) throws IOException {
        if (hawqFileStatuses == null) {
            throw new IllegalStateException("Please call HAWQParquetInputFormat.setInput first!");
        }

        if (hawqFileStatuses.length == 0) {
            return Lists.newArrayList(); // handle empty table
        }

        return super.getSplits(jobContext);
    }

    @Override
    protected List<FileStatus> listStatus(JobContext jobContext) throws IOException {
        List<FileStatus> result = Lists.newArrayList();
        for (HAWQFileStatus hawqFileStatus : hawqFileStatuses) {
            if (hawqFileStatus.getFileLength() == 0)
                continue; // skip empty file

            Path path = new Path(hawqFileStatus.getFilePath());
            FileSystem fs = path.getFileSystem(jobContext.getConfiguration());
            FileStatus dfsStat = fs.getFileStatus(path);
            // rewrite file length because HAWQ records the logicalEOF of file, which may
            // be smaller than the file's actual EOF
            FileStatus hawqStat = new FileStatus(hawqFileStatus.getFileLength(), // rewrite to logicalEOF
                    dfsStat.isDirectory(), dfsStat.getReplication(), dfsStat.getBlockSize(),
                    dfsStat.getModificationTime(), dfsStat.getAccessTime(), dfsStat.getPermission(),
                    dfsStat.getOwner(), dfsStat.getGroup(), dfsStat.getPath());
            result.add(hawqStat);
        }

        return result;
    }
}