ExecutionException

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Overview

ExecutionException is a checked exception that extends the Exception class. This exception is thrown by an instance of FutureTask that encounters an Exception or Error (both derivates of Throwable) that remain unhandled by user code and, subsequently an attempt is made to retrieve the result of such a task.

Example

Consider the program below that has a task submitted to the ExecutorService. The task simply throws a runtime exception to simulate failure. When we attempt to retrieve the result of the task, the snippet futureTask.get() throws ExecutionException.