How to Write a Simple SerDe?

[Rubin, Bradley S.]

My Hadoop MR job emits a value with three primitives via a custom Writable (see 
below).  How do I write a corresponding custom SerDe so that Hive can read the 
output from HDFS?  I can find complex SerDe examples (RegEx, JSON), but I can't 
find something simple to model from.

I think that my create table should look like this, correct?

CREATE EXTERNAL TABLE rats (time INT, frequency SMALLINT, convolution FLOAT)
ROW FORMAT SERDE 'neurohadoop.RatSerde'
STORED AS SEQUENCEFILE LOCATION '/neuro/output/rats';

----------

public class RatWritable implements Writable {
  int timestamp;
  short frequency;
  float convolution;
  
  public void readFields(DataInput in) throws IOException {
          timestamp = in.readInt();
          frequency = in.readShort();
          convolution = in.readFloat();
  }
  
  public void write(DataOutput out) throws IOException {
          out.writeInt(timestamp);
          out.writeShort(frequency);
          out.writeFloat(convolution);
  }
}

-- Brad