Java AWT Reference

13

AWT Exceptions and Errors

In this chapter:

• AWTException
• IllegalComponentStateException
• AWTError

This chapter describes AWTException, IllegalComponentStateException, and AWTError. AWTException is a subclass of Exception. It is not used by any of the public classes in java.awt; you may, however, find it convenient to throw AWTException within your own code. IllegalComponentStateException is another Exception subclass, which is new to Java 1.1. This exception is used when you try to do something with a Component that is not yet appropriate. AWTError is a subclass of Error that is thrown when a serious problem occurs in AWT—for example, the environment is unable to get the platform's Toolkit.

13.1 AWTException

AWTException is a generic exception that can be thrown when an exceptional condition has occurred within AWT. None of the AWT classes throw this. If you subclass any of the AWT classes, you can throw an AWTException to indicate a problem. Using AWTException is slightly preferable to creating your own Exception subclass because you do not have to generate another class file. Since it is a part of Java, AWTException is guaranteed to exist on the run-time platform.

If you throw an instance of AWTException, like any other Exception, it must be caught in a catch clause or declared in the throws clause of the method.

13.1.1 AWTException Method

Constructor

public AWTException (String message)

The sole constructor creates an AWTException with a detailed message of message. This ...