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FlexDoc/Javadoc 2.0 Demo Java Doc |
Executor executor = anExecutor();
executor.execute(new RunnableTask1());
executor.execute(new RunnableTask2());
...
However, the Executor interface does not strictly require
that execution be asynchronous. In the simplest case, an executor
can run the submitted task immediately in the caller's thread:
class DirectExecutor implements Executor {
public void execute(Runnable r) {
r.run();
}
}
More typically, tasks are executed in some thread other than the
caller's thread. The executor below spawns a new thread for each
task.
class ThreadPerTaskExecutor implements Executor {
public void execute(Runnable r) {
new Thread(r).start();
}
}
Many Executor implementations impose some sort of
limitation on how and when tasks are scheduled. The executor below
serializes the submission of tasks to a second executor,
illustrating a composite executor.
class SerialExecutor implements Executor {
final Queue<Runnable> tasks = new ArrayDeque<>();
final Executor executor;
Runnable active;
SerialExecutor(Executor executor) {
this.executor = executor;
}
public synchronized void execute(Runnable r) {
tasks.add(() -> {
try {
r.run();
} finally {
scheduleNext();
}
});
if (active == null) {
scheduleNext();
}
}
protected synchronized void scheduleNext() {
if ((active = tasks.poll()) != null) {
executor.execute(active);
}
}
}
The Executor implementations provided in this package
implement ExecutorService, which is a more extensive
interface. The ThreadPoolExecutor class provides an
extensible thread pool implementation. The Executors class
provides convenient factory methods for these Executors.
Memory consistency effects: Actions in a thread prior to submitting a Runnable object to an Executor happen-before its execution begins, perhaps in another thread.
Method Summary |
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void |
Executes the given command at some time in the future.
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void execute |
(Runnable command) |
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FlexDoc/Javadoc 2.0 Demo Java Doc |