Springboot integrates ThreadPoolTaskExecutor thread pool
- ThreadPoolExecutor: This is a thread pool execution class implemented by java. Basically, thread pools are created through this class
- ThreadPoolTaskExecutor: This is a thread pool execution class implemented by springboot based on ThreadPoolExecutor
In springboot, according to Official documents According to the official document, if the thread pool is not configured, springboot will automatically configure a ThreadPoolTaskExecutor thread pool into the bean. We just need to call it in its way.
Use the default thread pool of springboot
demo test, no thread pool is configured, and the default thread pool of springboot is adopted
Test method I:
First, add @ EnableAsync in the application startup class
@SpringBootApplication
@EnableAsync
public class ThreadpoolApplication {
public static void main(String[] args) {
SpringApplication.run(ThreadpoolApplication.class, args);
}
}
The second step is to add @ Async annotation to the methods that need to be executed asynchronously
@Service
public class AsyncTest {
protected final Logger logger = LoggerFactory.getLogger(this.getClass());
@Async
public void hello(String name){
//The logger is used here to check the thread of execution
logger.info("Asynchronous thread start started."+name);
}
}
The third step is to test and verify the test class
@Autowired
AsyncTest asyncTest;
@Test
void contextLoads() throws InterruptedException {
asyncTest.hello("afsasfasf");
//Be sure to sleep, otherwise the main thread is closed and the child thread has not been started
Thread.sleep(1000);
}
Log results:
INFO 2276 — [ main] c.h.s.t.t.ThreadpoolApplicationTests : Started ThreadpoolApplicationTests in 3.003 seconds (JVM running for 5.342) INFO 2276 — [ task-1] c.h.s.threadpool.threadpool.AsyncTest: asynchronous thread started afsasfasf
See that a new task-1 thread is opened to execute tasks. Validation succeeded.
Test method 2:
Directly call ThreadPoolTaskExecutor, modify the next test class, and directly inject ThreadPoolTaskExecutor
@Autowired
AsyncTest asyncTest;
@Autowired
ThreadPoolTaskExecutor threadPoolTaskExecutor;
@Test
void contextLoads() throws InterruptedException {
asyncTest.hello("async Annotation creation");
threadPoolTaskExecutor.submit(new Thread(()->{
logger.info("threadPoolTaskExecutor Create thread");
}));
//Be sure to sleep, otherwise the main thread is closed and the child thread has not been started
Thread.sleep(1000);
}
Print log:
INFO 12360 - [TASK-2] c.h.s.t.t.threadpoolapplicationtests: threadpooltaskexecutor creates thread INFO 12360 - [TASK-1] c.h.s.threadpool threadpool. Asynctest: asynchronous thread started Async annotation creation
Note 1: if you only use ThreadPoolTaskExecutor, you don't need to add @ EnableAsync annotation on the Application startup class.
Note 2: several tests found that ThreadPoolTaskExecutor executes faster than @ Async.
Thread pool default configuration information
It can be found in application Make relevant settings in the properties file.
# Number of core threads spring.task.execution.pool.core-size=8 # Maximum number of threads spring.task.execution.pool.max-size=16 # Idle thread lifetime spring.task.execution.pool.keep-alive=60s # Allow core thread timeout spring.task.execution.pool.allow-core-thread-timeout=true # Number of thread queues spring.task.execution.pool.queue-capacity=100 # Thread shutdown wait spring.task.execution.shutdown.await-termination=false spring.task.execution.shutdown.await-termination-period= # Thread name prefix spring.task.execution.thread-name-prefix=task-
Using a custom thread pool
First, create a ThreadPoolConfig, configure a thread pool, and set the rejection policy to CallerRunsPolicy
@Configuration
public class ThreadPoolConfig {
@Bean("taskExecutor")
public Executor taskExecutor() {
ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
//Setting thread pool parameter information
taskExecutor.setCorePoolSize(10);
taskExecutor.setMaxPoolSize(50);
taskExecutor.setQueueCapacity(200);
taskExecutor.setKeepAliveSeconds(60);
taskExecutor.setThreadNamePrefix("myExecutor--");
taskExecutor.setWaitForTasksToCompleteOnShutdown(true);
taskExecutor.setAwaitTerminationSeconds(60);
//Modify the reject policy to execute with the current thread
taskExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
//Initialize thread pool
taskExecutor.initialize();
return taskExecutor;
}
}
Then execute the test code written before and find that the thread pool used has become a custom thread pool
INFO 12740 - [myExecutor – 2] c.h.s.t.t.threadpoolapplicationtests: threadpooltaskexecutor creates thread INFO 12740 - [myExecutor – 1] c.h.s.threadpool threadpool. Asynctest: asynchronous thread started Async annotation creation
If multiple thread pools are configured, how to specify thread pools?
@Configuration
public class ThreadPoolConfig {
@Bean("taskExecutor")
public Executor taskExecutor() {
ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
//Setting thread pool parameter information
taskExecutor.setCorePoolSize(10);
taskExecutor.setMaxPoolSize(50);
taskExecutor.setQueueCapacity(200);
taskExecutor.setKeepAliveSeconds(60);
taskExecutor.setThreadNamePrefix("myExecutor--");
taskExecutor.setWaitForTasksToCompleteOnShutdown(true);
taskExecutor.setAwaitTerminationSeconds(60);
//Modify the reject policy to execute with the current thread
taskExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
//Initialize thread pool
taskExecutor.initialize();
return taskExecutor;
}
@Bean("poolExecutor")
public Executor poolExecutor() {
ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
//Setting thread pool parameter information
taskExecutor.setCorePoolSize(10);
taskExecutor.setMaxPoolSize(50);
taskExecutor.setQueueCapacity(200);
taskExecutor.setKeepAliveSeconds(60);
taskExecutor.setThreadNamePrefix("myExecutor2--");
taskExecutor.setWaitForTasksToCompleteOnShutdown(true);
taskExecutor.setAwaitTerminationSeconds(60);
//Modify the reject policy to execute with the current thread
taskExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
//Initialize thread pool
taskExecutor.initialize();
return taskExecutor;
}
}
Execution result:
No qualifying bean of type 'org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor' available: expected single matching bean but found 2: taskExecutor,taskPoolExecutor
Execute the test class, directly report an error, say that multiple classes are found, and do not know which class to load
Since the test class is automatically injected in this way:
@Autowired ThreadPoolTaskExecutor threadPoolTaskExecutor;
Considering the problem of how to match multiple classes when @ Autowired and @ Resources are injected, as long as the bean to be injected is specified during use, the corresponding thread pool will be called.
@Autowired
AsyncTest asyncTest;
@Autowired
ThreadPoolTaskExecutor poolExecutor; //Will match the thread pool @ Bean("poolExecutor")
@Test
void contextLoads() throws InterruptedException {
asyncTest.hello("async Annotation creation");
//Be sure to sleep, otherwise the main thread is closed and the child thread has not been started
poolExecutor.submit(new Thread(()->{
logger.info("threadPoolTaskExecutor Create thread");
}));
Thread.sleep(1000);
}
Print log:
INFO 13636 - [myExecutor2 – 1] c.h.s.t.t.threadpoolapplicationtests: threadpooltaskexecutor creates thread INFO 13636 - [myExecutor – 1] c.h.s.threadpool threadpool. Asynctest: asynchronous thread started Async annotation creation
Note 1: if @ Async annotation is used, you only need to specify the bean name in the annotation to switch the corresponding thread pool, as shown below:
@Async("taskPoolExecutor")
public void hello(String name){
logger.info("Asynchronous thread start started."+name);
}
Note 2: if there are multiple thread pools, but they are not specified in the @ Async annotation, the first configured thread pool will be loaded by default.