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Daffodil has a Java API. Attached to this page is a helloWorld.zip which is the Daffodil/DFDL version of a hello world program. It parses some data "Hello world! " into XML and unparses it back, calling Daffodil from the Java API. It's is self contained so just unzip it. You need sbt 0.13 to build it, and this will pull daffodil's jars and everything else they depend on to your machine automatically. If you have sbt then just typing the command "sbt run" in the root directory where you unzipped this will do all of it. Look in the src/main/java/HelloWorld.java file to see how the Java API works.
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