How to fail Phing without triggering backtrace
问题 Before my main phing task runs, it first checks that all required properties have been set. If a property is missing or invalid, it calls a FailTask to end execution - which works. <if> <equals arg1="${build.db.host}" arg2="" /> <then> <fail msg="build.db.host is empty." /> </then> </if> Alas, the FailTask throws a BuildException (with the msg), which throws an 'error in IfTask' - both of which are displayed twice, with their backtraces, giving me a 60-line screen dump for a one line message!