As we started using Protobuf, it is important to know how you make changes to .proto files and how to compile them. Easiest way:

1. Download protobuf compiler from:

2. Install protobuf-dt eclipse plugin as detailed here:

3. Configure the destination directory to generate the java files as detailed in step 2 here:

Set the "Java Output Directory" to: src/main/java

4. VERY IMPORTANT FOR JBPM: jBPM Flow project has a .proto file that extends the data types defined in the .proto file in Drools Core, so you need to configure the protobuf import path as detailed here:

Add the following import paths to the jbpm-flow project:

${your drools-core project in eclipse}/src/main/resources

   After doing that, when you edit and save the .proto files, eclipse will automatically compile and regenerate the java source code for them.


  Edson Tirelli
  JBoss Drools Core Development
  JBoss by Red Hat @