I'm using Netbeans 8.02 with JDK 8 update 31 on Mac OSx Yosemite 10.10.2.  I'm getting the following error when trying to build an application image:
 
Creating app bundle: /Users/scottselvia/Documents/JavaFXApplication4/dist/bundles/JavaFXApplication4.app
java.io.IOException: Exec failed with code 1 command [[codesign, -f, -s, Developer ID Application: , -vvvv, /Users/scottselvia/Documents/JavaFXApplication4/dist/bundles/JavaFXApplication4.app/Contents/Java/JavaFXApplication4.jar] in unspecified directory
/Users/scottselvia/Documents/JavaFXApplication4/nbproject/jfx-impl.xml:3415: The following error occurred while executing this line:
/Users/scottselvia/Documents/JavaFXApplication4/nbproject/jfx-impl.xml:3438: The following error occurred while executing this line:
/Users/scottselvia/Documents/JavaFXApplication4/nbproject/jfx-impl.xml:1465: The following error occurred while executing this line:
/Users/scottselvia/Documents/JavaFXApplication4/nbproject/jfx-impl.xml:3093: The following error occurred while executing this line:
/Users/scottselvia/Documents/JavaFXApplication4/nbproject/jfx-impl.xml:2055: Error: Bundler "Mac Application Image" (mac.app) failed to produce a bundle.
BUILD FAILED (total time: 4 seconds)