public void shouldConcat2Fields() throws Exception {
List<String> fields = new ArrayList<String>();
fields.add("field1");
fields.add("field2");
ConcatAction action = new ConcatAction();
action.setFields(fields);
action.setDestField("field3");
action.setSeparator(",");
Message message = new Message();
message.setProperty("field1", "value1");
message.setProperty("field2", "value2");
action.execute(message);
Assert.assertEquals(message.getProperty("field3", String.class), "value1,value2");
}