public final class ExecutionList extends Object
A support class for ListenableFuture
implementations to manage their listeners. An instance contains a list of listeners, each with an associated Executor
, and guarantees that every Runnable
that is added will be executed after execute()
is called. Any Runnable
added after the call to execute
is still guaranteed to execute. There is no guarantee, however, that listeners will be executed in the order that they are added.
Exceptions thrown by a listener will be propagated up to the executor. Any exception thrown during Executor.execute
(e.g., a RejectedExecutionException
or an exception thrown by direct execution) will be caught and logged.
Constructor and Description |
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ExecutionList()
Creates a new, empty
ExecutionList . |
Modifier and Type | Method and Description |
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void |
add(Runnable runnable,
Executor executor)
Adds the
Runnable and accompanying Executor to the list of listeners to execute. |
void |
execute()
Runs this execution list, executing all existing pairs in the order they were added.
|
public ExecutionList()
Creates a new, empty ExecutionList
.
public void add(Runnable runnable, Executor executor)
Adds the Runnable
and accompanying Executor
to the list of listeners to execute. If execution has already begun, the listener is executed immediately.
When selecting an executor, note that directExecutor
is dangerous in some cases. See the discussion in the ListenableFuture.addListener
documentation.
public void execute()
Runs this execution list, executing all existing pairs in the order they were added. However, note that listeners added after this point may be executed before those previously added, and note that the execution order of all listeners is ultimately chosen by the implementations of the supplied executors.
This method is idempotent. Calling it several times in parallel is semantically equivalent to calling it exactly once.
run
)