The Apache Pig project's User Defined Functions gives a pretty good overview of how to create a UDF. In fact, I stole my simple UDF from there. For Pig UDF's the "Hello World" program is actually a "Convert to Upper Case" function. For this effort, I'm using the Hortonworks Sandbox (version 2.0). Once you have that setup operational, follow along and we'll get your first UDF created and placed on HDFS where others can easily share it.
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