How to get rosjava generate classes instead of interfaces ?

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Hi,

I followed the rosjava tutorials for 'unofficial messages' for Hydro. It all works, but I get an interface .java file instead of a class. For example:

scip_api/msgs/Alarm.msg:

string alarm_name
string data_name

scip_api/build/generated-src/scip_api/Alarm.java:

package scip_api;

public interface Alarm extends org.ros.internal.message.Message {
  static final java.lang.String _TYPE = "scip_api/Alarm";
  static final java.lang.String _DEFINITION = "string alarm_name\nstring data_name";
  java.lang.String getAlarmName();
  void setAlarmName(java.lang.String value);
  java.lang.String getDataName();
  void setDataName(java.lang.String value);
}

While for the std_msgs types, the generated .java file is a class (at least for String.msg it is)

What did I do wrong ? I used the released ros-hydro-rosjava packages for Ubuntu 12.04