Didn't get it? Both Netbeans and JCreator are tools/editor for java. Code written in one should be directly usable in the other.
Only thing I see is if you have used the netbeans provided classes. In that case, you have to put the jars in the system classpath and/or reference them in the jcreator project.
Shouldn't be tough. All the best.
Netbeans uses some specific libs that do not exist in JCreator, then you must add these libs manually to JCreator, it is not enough to copy them to the class path dir.
form JCreator window open Configure menu and choose Options. then select JDK Profiles from the left pane tree. on the right pane select JDK version 1.x.x and push the Edit... button. from the Classes tab press Add button and select Add Archive... then browse your lib(s).
good luck.
Ahmad Elsafty