### Question:
DependencyGraphServiceImpl extends ServiceSupport implements DependencyGraphService { public void triggerDependents(final AbstractBuild<?, ?> build, final TaskListener listener) { checkNotNull(build, "build"); checkNotNull(listener, "listener"); if (log.isDebugEnabled()) { log.debug("Maybe triggering dependents of build: {}", build.getFullDisplayName()); } BuildTrigger.execute(build, (BuildListener) listener); }  DependencyGraph getGraph(); void rebuild(); void triggerDependents(final AbstractBuild<?, ?> build, final TaskListener listener);  }### Answer:
@Test(expected=NullPointerException.class) public void triggerDependentsNullArg1() { getInst().triggerDependents(null, listener); }
@Test(expected=NullPointerException.class) public void triggerDependentsNullArg2() { getInst().triggerDependents(build, null); }