how to programmatically dump data(bulk write) to elastic search

I am trying to learn the ropes of elastic search. As part of QA testing, I want to write massive number of records to ES(say 10K records). Each record is a geo location (x,y) coordinate. Each write will arbitrarily increase the value of (x,y). I can have a counter that I can update in every loop operation in Java and write to ES. But I am guessing there may be a better way (because in ES documentation, I come across _bulk keyword). Is there any ES way of doing massive programmatic writes to ES