Crashes on null pointer exception at the end of the build process.

ERROR: Build step failed with exception
17:02:47 java.lang.NullPointerException
17:02:47 at au.com.rayh.XCodeBuilder.perform(XCodeBuilder.java:738)
17:02:47 at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
17:02:47 at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:782)
17:02:47 at hudson.model.Build$BuildExecution.build(Build.java:205)
17:02:47 at hudson.model.Build$BuildExecution.doRun(Build.java:162)
17:02:47 at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:534)
17:02:47 at hudson.model.Run.execute(Run.java:1738)
17:02:47 at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
17:02:47 at hudson.model.ResourceController.execute(ResourceController.java:98)
17:02:47 at hudson.model.Executor.run(Executor.java:410)
17:02:47 Build step 'Xcode' marked build as failure