Spring - Task Execution Introduction

Spring Core framework provides abstraction of task execution. Task execution is referred as creating a new thread and perform some task in it. Spring's task execution abstraction hides implementation differences between Java SE 1.4, Java SE 5 and Java EE environments. Spring underlying implementation can be based on Java Executor framework or a simple Java thread or even it can be based on a third party library like Quartz.

The interfaces

Definition of TaskExecutor

 package org.springframework.core.task;
 @FunctionalInterface
 public interface TaskExecutor extends Executor {
     void execute(Runnable task); 
 }

Definition of AsyncTaskExecutor

 package org.springframework.core.task;
 public interface AsyncTaskExecutor extends TaskExecutor {
     default void execute(Runnable task, 1
                          long startTimeout);
     default Future<?> submit(Runnable task); 2
     default <T> Future<T> submit(Callable<T> task); 3
     default CompletableFuture<Void> submitCompletable(Runnable task); 4
     default <T> CompletableFuture<T> submitCompletable(Callable<T> task);
         5
 }

Definition of AsyncListenableTaskExecutor

 package org.springframework.core.task;
 @Deprecated(since = "6.0", forRemoval = true)
 @SuppressWarnings("removal")
 public interface AsyncListenableTaskExecutor extends AsyncTaskExecutor {
     org.springframework.util.concurrent.ListenableFuture<?>
         submitListenable(Runnable task); 1
     <T> org.springframework.util.concurrent.ListenableFuture<T>
         submitListenable(Callable<T> task); 2
 }

AsyncListenableTaskExecutor has been deprecated in 6.0, in favor of AsyncTaskExecutor.submitCompletable(Runnable) and AsyncTaskExecutor.submitCompletable(Callable)

AsyncListenableTaskExecutor has been removed in Spring 7.0.

Definition of ListenableFuture

 package org.springframework.util.concurrent;
 @Deprecated(since = "6.0", forRemoval = true)
 public interface ListenableFuture<T> extends Future<T> {
     void addCallback(ListenableFutureCallback<? super T> callback); 1
     void addCallback(SuccessCallback<? super T> successCallback, 2
                      FailureCallback failureCallback);
     default CompletableFuture<T> completable(); 3
 }

This class has been removed in Spring 7.0.

Definition of SuccessCallback

 package org.springframework.util.concurrent;
 @Deprecated(since = "6.0", forRemoval = true)
 @FunctionalInterface
 public interface SuccessCallback<T> {
     void onSuccess(@Nullable T result); 1
 }

SuccessCallback has been removed in Sping 7.0.

Definition of FailureCallback

 package org.springframework.util.concurrent;
 @Deprecated(since = "6.0", forRemoval = true)
 @FunctionalInterface
 public interface FailureCallback {
     void onFailure(Throwable ex); 1
 }

FailureCallback has been removed in Spring 7.0.

In this tutorial we have introduced commonly used task executors. There are more. Please checkout reference document TaskExecutor types list. In the next tutorial we will give examples for Spring TaskExecutor implementation.