Executable is a functional interface that can be used to implement any generic block of code that potentially throws a Throwable.

The Executable interface is similar to java.lang.Runnable, except that an Executable can throw any kind of exception.

Rationale for throwing Throwable instead of Exception

Although Java applications typically throw exceptions that are instances of java.lang.Exception, java.lang.RuntimeException, java.lang.Error, or java.lang.AssertionError (in testing scenarios), there may be use cases where an Executable needs to explicitly throw a Throwable. In order to support such specialized use cases, execute() is declared to throw Throwable.