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.pig.EvalFunc;
  import org.apache.pig.data.DataType;
  import org.apache.pig.data.Tuple;
  import org.apache.pig.impl.logicalLayer.FrontendException;
  import org.apache.pig.impl.logicalLayer.schema.Schema;
  
  public class TimePartition extends EvalFunc<Long>{
  
    protected long period = 0;
    
    public TimePartition(String strPeriod) {
      period = Long.parseLong(strPeriod);
    }
   
    @Override
    public Long exec(Tuple input) throws IOException {
      if (input == null || input.size() < 1)
        return null;
      try {
        long timestamp = Long.parseLong(input.get(0).toString());
        timestamp =  timestamp - (timestamp % (period));
        
        return timestamp;
      } catch (Exception e) {
        e.printStackTrace();
        return null;
      }
    }
  
    @Override
    public Schema outputSchema(Schema input) {
      Schema schema = null;
      try {
        schema = new Schema(new Schema.FieldSchema(input.getField(0).alias, DataType.LONG));
      } catch (FrontendException e) {
        schema = new Schema(new Schema.FieldSchema(getSchemaName("timePartition", input),
            DataType.LONG));
      }
      return schema;
    }
  
  }
  