Balking pattern

The Balking pattern is a software design pattern that only executes an action on an object when the object is in a particular state. For example, if an object reads ZIP files and a calling method invokes a get method on the object when the ZIP file is not open, the object would "balk" at the request. In Java, an "IllegalStateException" could be thrown.

See also: Read and write lock pattern, Guarded suspension pattern