content: /*
   * 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.apache.hadoop.chukwa;
  
  import java.io.IOException;
  import org.apache.hadoop.mapreduce.Job;
  import org.apache.hadoop.mapreduce.InputFormat;
  import org.apache.hadoop.mapreduce.RecordReader;
  import org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat;
  import org.apache.hadoop.mapreduce.lib.input.SequenceFileRecordReader;
  import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
  import org.apache.pig.LoadFunc;
  import org.apache.pig.LoadMetadata;
  import org.apache.pig.ResourceSchema;
  import org.apache.pig.ResourceStatistics;
  import org.apache.pig.Expression;
  import org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit;
  import org.apache.pig.data.DataType;
  import org.apache.pig.data.DefaultTupleFactory;
  import org.apache.pig.data.Tuple;
  import org.apache.pig.data.DataByteArray;
  import org.apache.pig.data.TupleFactory;
  import org.apache.pig.impl.logicalLayer.schema.Schema;
  import static org.apache.pig.impl.logicalLayer.schema.Schema.FieldSchema;
  
  public class ChukwaArchive extends LoadFunc implements LoadMetadata {
  
    SequenceFileRecordReader<ChukwaArchiveKey, ChunkImpl> reader;
  
    private TupleFactory tf = DefaultTupleFactory.getInstance();
    
    static Schema chukwaArchiveSchema;
    static ResourceSchema chukwaArchiveResourceSchema;
    static int schemaFieldCount;
    static {
      chukwaArchiveSchema = new Schema();
      chukwaArchiveSchema.add(new FieldSchema("seqNo", DataType.LONG));
      chukwaArchiveSchema.add(new FieldSchema("type", DataType.CHARARRAY));
      chukwaArchiveSchema.add(new FieldSchema("name", DataType.CHARARRAY));
      chukwaArchiveSchema.add(new FieldSchema("source", DataType.CHARARRAY));
      chukwaArchiveSchema.add(new FieldSchema("tags", DataType.CHARARRAY));
      chukwaArchiveSchema.add(new FieldSchema("data", DataType.BYTEARRAY));
      schemaFieldCount = chukwaArchiveSchema.size();
      chukwaArchiveResourceSchema = new ResourceSchema(chukwaArchiveSchema);
      //do we want to expose the record offsets?
    }
  
    @Override
    public Tuple getNext() throws IOException {
      
      try {
        if (!reader.nextKeyValue()) {
          return null;
        }
      } catch (InterruptedException e) {
          throw new IOException(e);
      }
  
      ChunkImpl val = ChunkImpl.getBlankChunk();
      Tuple t = tf.newTuple(schemaFieldCount);
      t.set(0, new Long(val.seqID));
      t.set(1, val.getDataType());
      t.set(2, val.getStreamName());
      t.set(3, val.getSource());
      t.set(4, val.getTags());
      byte[] data = val.getData();
    
      t.set(5, (data == null) ? new DataByteArray() : new DataByteArray(data));
      
  //    System.out.println("returning " + t);
      return t;
    }
  
    @Override
    public ResourceSchema getSchema(String s, Job job) throws IOException {
      return chukwaArchiveResourceSchema;
    }
  
    @Override
    public ResourceStatistics getStatistics(String s, Job job) throws IOException {
      return null;
    }
  
    @Override
    public String[] getPartitionKeys(String s, Job job) throws IOException {
      return null;
    }
  
    @Override
    public void setPartitionFilter(Expression expression) throws IOException {
    }
  
    @SuppressWarnings("unchecked")
    @Override
    public InputFormat getInputFormat() throws IOException {
      return new SequenceFileInputFormat<ChukwaArchiveKey, ChunkImpl>();
    }
  
    @SuppressWarnings("unchecked")
    @Override
    public void prepareToRead(RecordReader reader, PigSplit split) throws IOException {
      this.reader = (SequenceFileRecordReader)reader;
    }
  
    @Override
    public void setLocation(String location, Job job) throws IOException {
      FileInputFormat.setInputPaths(job, location);
    }
  }
  