I have a problem at the moment of executing my program, I get a hammer where the classes are and he does not let me execute it. That hammer appears to me:
The weird thing is that all the classes are there and the frames but he does not let them run, can anyone help me?
You have to right click on the project, and click on Property, sometimes the "hammer" that appears is because you have some problem with a library or file .jar
When you open the Properties window of your project, check the Sources and Libraries options. In one of those two may be the problem. Sometimes it's just adding the library or .jar file correctly or you just have to delete an incorrect path.