How to define multiple qualified thread pools with AsyncConfigurer - java

Spring framework has an interface AsyncConfigurer (and AsyncConfigurerSupport) for configuring everything necessary for having a thread pool executor and being able to run methods asynchronously (with #Async).
But usually, it's not a good practice to share the same thread pool among different functionalities, so usually I qualified them with a name, and I specify that name in Async annotation for it to use one specific thread pool.
Thing is, I would like to configure them through this convenient interface AsyncConfigurer and not loosing qualification, but I'm not able to.
Trying this:
#Configuration
#EnableAsync
public class PusherAsyncConfigurerSupport extends AsyncConfigurerSupport {
#Autowired
ExecutorConfig config;
#Override
#Qualifier(value = "executorOne")
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(config.getCorePoolSize());
...
executor.initialize();
return executor;
}
#Override
public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
return new MyAsyncUncaughtExceptionHandler();
}
}
That thread pool is still not recognized when put in an Async annotation.
So, what is it needed for configuring several thread pools this way? Or isn't it the way for that at all?

mark with #Bean annotation
#Bean
#Qualifier(value = "executorOne")
public Executor getAsyncExecutor() {
//..
return executor;
}

Related

Spring Boot: Can we have seperate thread pool for each request?

I've implemented asynchronous execution for a method in my application using Spring Boot #Async. I'm having a custom thread pool with 20 thread. In a for loop calling the async method for 30 times.
Each individual request is executing asynchronously but when i made two different requests at the same time to my API from browser, first request is executing and then second. Not both requests executing the same method parallely.
I thought when first request reach the app, it's started executing the async method and since it's being executing for 30 times and my pool is having 20 threads, all threads are busy in executing first request. So even second request came for execution also since the pool of threads busy, the other request is waiting till a thread becomes free in the pool.
Can we have separate thread pool for each individual request. or any way that we can make execution of each request separate independent of other request processing.
Here is my code sample.
#SpringBootApplication
#EnableAsync
public class AppBootStrap
{
public static void main(String[] args)
{
SpringApplication.run(AppBootStrap.class, args);
}
#Bean
public AsyncTaskService asyncTaskService() {
return new AsyncTaskService();
}
#Bean(name="customExecutor")
public Executor taskExecutor() {
ThreadPoolTaskExecutor poolExecutor = new ThreadPoolTaskExecutor();
poolExecutor.setCorePoolSize(10);
poolExecutor.setMaxPoolSize(20);
poolExecutor.setThreadNamePrefix("customPoolExecutor");
poolExecutor.initialize();
return poolExecutor;
}
}
**Controller Class:**
#RestController
public class TaskController
{
#Autowired
private TaskService taskService;
#RequestMapping("/performAction")
public void performAction() {
taskService.performAction();
}
}
**Service class**
#Service
public class TaskService
{
#Autowired
private AsyncTaskService asyncTaskService;
public void performAction()
{
for(int i = 0; i < 30; i++) {
asyncTaskService.greetings(i);
}
}
}
**Async Method Class**
public class AsyncTaskService
{
#Async
public void greetings(Integer i)
{
try
{
Thread.sleep(500 * (i + 10));
}
catch (InterruptedException e)
{
e.printStackTrace();
}
System.out.println("Welcome to Async Service: " + i);
}
}
#Bean(name = "apiTaskExecutor")
public ThreadPoolTaskExecutor apiTaskExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(20);
executor.setMaxPoolSize(100);
executor.setQueueCapacity(50);
executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
executor.initialize();
return executor;
}
#Bean(name = "lruTaskExecutor")
public ThreadPoolTaskExecutor lruTaskExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(100);
executor.setMaxPoolSize(200);
executor.setQueueCapacity(500);
executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
executor.initialize();
return executor;
}
The Way to do this is to create two Thread different Thread Pools using Different Qualifier names. (As shown above)
#Autowired
#Qualifier("apiTaskExecutor")
private ThreadPoolTaskExecutor apiTaskExecutor;
Then autowire the required pool using the qualifier you have given . You can also use the #Async annotation instead of autowiring . I prefer this way.
If I am not wrong this way of having different thread pools for different Tasks is known as bulkhead pattern.
I think the problem is that the customExecutor bean is a singleton. This means that when the second request tries to use this bean it finds all the threads of the thred pool busy. You can try to make the customExecutor bean non-singleton by using the #Scope("prototype") annotation which will cause a new one to be instantiated whenever a bean of this type is requested.

Autowiring multiple SimpleJobLaunchers

I have a class which I want to run jobs from asynchronously. To do this I have the following code:
#Resource
private SimpleJobLauncher jobLauncher;
#PostConstruct
public void initLauncher(){
jobLauncher.setTaskExecutor(taskExecutor());
}
However, there is a situation where I need to do this synchronously. So, what I have done is added the following variable:
#Resource
private SimpleJobLauncher synchronousJobLauncher;
Which I hoped wouldn't have the taskExecutor on it making it synchronous. I then pass the synchronousJobLauncher to the places where I want to do things synchronously. However, using the synchronousJobLauncher gives me the same error as when I use the asynchronous one which leads me to believe that you cannot autowire the same variable twice like I am trying to do. If I do not do the #PostConstruct part of the code, the synchronous part works like I expect but not the asynchronous part, even though they use, what I think are, different job launchers.
Any ideas? I have tried using the #Resource annotation instead of #Autowired.
I haven't used SimpleJobLaunchers, but normally, in Spring I always used the #Async annotation, which make asynchronous execution quite simple. All you have to do is add this annotation, #EnableAsync in any configuration file, just like the one below.
#Configuration
#EnableAsync
public class MvcConfig extends WebMvcConfigurerAdapter { ... }
Now, is all about adding the #Async to any method that will run asynchronously.
#Component
class AsyncTask {
#Async
public Future<String> run() throws InterruptedException {
return new AsyncResult<String>("return value");
}
}
And if you want to wait for the result, you can do the following.
public void callAsyncTask() {
try {
Future<String> future = asyncTask.run();
// Do some other things while the async task is running.
// future.get() will block the function and wait for the result.
String asyncResult = future.get();
} catch(InterruptedException e) {
e.printStackTrace();
// Do something else.
}
}
Hope this helps. I know is not directly what you were asking for, but maybe this solution can facilitate your problem.
You can create two job launchers (one synchronous and one asynchronous) then inject the one you want using a qualifier. By default, the SimpleJobLauncher uses a synchronous task executor, so you need to configure a task executor only for the asynchronous one. Here is an example:
#Bean
public SimpleJobLauncher synchronousJobLauncher() {
return new SimpleJobLauncher();
}
#Bean
public ThreadPoolTaskExecutor threadPoolTaskExecutor() {
return new ThreadPoolTaskExecutor();
}
#Bean
public SimpleJobLauncher asynchronousJobLauncher() {
SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
jobLauncher.setTaskExecutor(threadPoolTaskExecutor());
return jobLauncher;
}
Then, inject the job launcher you want with a #Qualifier("synchronousJobLauncher") or #Qualifier("asynchronousJobLauncher") according to your needs.
Hope this helps.

Where should I put #EnableAsync annotation

I need to send a email in async way while saving the data into DB.
My approach was like this.
//I have tried with service layer annotating.But not worked.
#EnableAsync
class MyService{
public String saveMethod(List listOfData){
mail.sendEmailQuote(listOfData);
mail.sendEmailWorkflowTaskAssignment(listOfData);
myDao.saveData(listOfData);
}
}
I need to perform following methods in #Async way. Where should I put #EnableAsync annotation. This is not a Schedule related thing. This is happen when user click save button. Application is used flex spring blazeDS. There is no controller written by my self.
I have used #Async annotation in my code for following 2 methods. Those are in class call Mail.
#Async
sendEmailQuote(listOfData){}
#Async
sendEmailWorkflowTaskAssignment(listOfData){}
Could you help me to find where should I put #EnableAsync ?
I refer this sample
EnableAsync is used for configuration and enable Spring's asynchronous method execution capability, it should not be put on your Service or Component class, it should be put on your Configuration class like:
#Configuration
#EnableAsync
public class AppConfig {
}
Or with more configuration of your AsyncExecutor like:
#Configuration
#EnableAsync
public class AppConfig implements AsyncConfigurer {
#Override
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(7);
executor.setMaxPoolSize(42);
executor.setQueueCapacity(11);
executor.setThreadNamePrefix("MyExecutor-");
executor.initialize();
return executor;
}
}
Please refer to it's java doc for more details.
And for the tutorial you followed, EnableAsync is put above Application class, which extends AsyncConfigurerSupport with AsyncExecutor configuration:
#SpringBootApplication
#EnableAsync
public class Application extends AsyncConfigurerSupport {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Override
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(2);
executor.setMaxPoolSize(2);
executor.setQueueCapacity(500);
executor.setThreadNamePrefix("GithubLookup-");
executor.initialize();
return executor;
}
}
Just make sure that #Async methods aren't called by the same class. Self invocation for proxy won't work.

Run multiple instances of the SAME cron job in Spring

I want to be able to run the SAME scheduled job in Spring.
After searching on the Internet, I figured out how to run multiple different jobs at the same time.
I have a #Service annotated class which has only one method, annotated with #Scheduled. I want to have multiple instances of this job running at the same time.
I am not using Quartz or Spring Batch( I have seen a lot of examples with Spring Batch).
The documentation doesn't clearly say if this can be achieved.
Yes, it can be easily achieved, but not with #Scheduled annotation.
How? Let me first explain how Spring works.
Spring from every method annotated with #Scheduled creates a new Runnable object and then schedules it for execution to the TaskScheduler (ThreadPoolTaskScheduler to be precise).
To see the exact code look at ScheduledAnnotationBeanPostProcessor.processScheduled().
So to fulfill your requirement: have multiple instances of the same job, but without using Quartz or Spring Batch we need to abandon #Scheduled annotation and do something a bit different than what the ScheduledAnnotationBeanPostProcessor does by default.
#Configuration
public class SpringConfig {
#Autowired
private TaskScheduler scheduler;
#Autowired
private YourServiceAnnotatedClass service;
#PostConstruct
public void startJobs() {
int numOfJobInstances = 3;
List<ImportantJob> jobs = IntStream.range(0, numOfJobInstances)
.mapToObj(i -> new ImportantJob("job" + i, service))
.collect(Collectors.toList());
jobs.forEach(this::schedule);
}
private void schedule(ImportantJob job) {
scheduler.schedule(job, new CronTrigger("*/5 * * * * *"));
// Above CronTrigger with 5 seconds was used, but feel free to use other variants, e.g.
// scheduler.scheduleAtFixedRate()
// scheduler.scheduleWithFixedDelay()
}
#Bean(destroyMethod = "shutdown")
public TaskScheduler taskScheduler() {
ThreadPoolTaskScheduler taskScheduler = new ThreadPoolTaskScheduler();
taskScheduler.setPoolSize(3); // Adjust it to your needs
return taskScheduler;
}
}
class ImportantJob implements Runnable {
private final String name;
private final YourServiceAnnotatedClass service;
public ImportantJob(String name, YourServiceAnnotatedClass service) {
this.name = name;
this.service = service;
}
#Override
public void run() {
service.doSth();
}
}
As you can see, although #Scheduled is useful and simple, it is not very flexible. But with some effort you can gain much more control over scheduled tasks.

How to go from XML Spring scheduling configuration to annotation/code configuration?

I am trying to convert the following Spring task xml configuration to a purely code/annotation based version:
<task:executor id="xyz.executor"
pool-size="${xyz.job.executor.pool.size:1-40}"
queue-capacity="${xyz.job.executor.queue.capacity:0}"
rejection-policy="CALLER_RUNS"/>
<task:scheduler id="xyz.scheduler" pool size="${xyz.job.scheduler.pool.size:4}" />
<task:annotation-driven executor="xyz.executor" scheduler="xyz.scheduler" />
<bean id='xyzProcessor' class="xyz.queueing.QueueProcessor" />
<task:scheduled-tasks scheduler="xyz.scheduler" >
<task:scheduled ref="partitioner" method="createPartitions" cron="${xyz.job.partitioner.interval:0 0 3 * * *}" />
</task:scheduled-tasks>
Per the Spring spec, 28.4.1 (http://docs.spring.io/spring/docs/current/spring-framework-reference/html/scheduling.html), they say that to go from XML like this:
<task:annotation-driven executor="myExecutor" scheduler="myScheduler"/>
<task:executor id="myExecutor" pool-size="5"/>
<task:scheduler id="myScheduler" pool-size="10"/>
to code configuration is as simply as enabling either #EnableScheduling and/or #EnableAsync.
However, I don't see anywhere I can actually instantiate the scheduler. The javadoc for #EnableScheduling (http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/scheduling/annotation/EnableScheduling.html) shows how I can get plug in my own created Executor, though I'm not exactly sure what class it should be (I still want to be able to control the pool size, queue capacity, and rejection policy). It also shows how I can schedule my createPartitions method using the configureTasks override. However, I would like to be able to name my scheduler (so I can identify its threads) and control its pool size.
So, I wish to know these things:
1) What class can I use to set the executor fields that the XML has?
2) Is there a way to create a scheduler instance that I can control the name and pool size of?
Check out the types AsyncConfigurer, AsyncConfigurerSupport, and SchedulingConfigurer. They are helper types you can use to enhance your #Configuration class with async/scheduling configurations.
Across all of them, and the javadoc of #EnabledAsync, you'll find all the setup methods you need to setup your async/scheduling #Configuration class.
The example given equates
#Configuration
#EnableAsync
public class AppConfig implements AsyncConfigurer {
#Bean
public MyAsyncBean asyncBean() {
return new MyAsyncBean();
}
#Override
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(7);
executor.setMaxPoolSize(42);
executor.setQueueCapacity(11);
executor.setThreadNamePrefix("MyExecutor-");
executor.initialize();
return executor;
}
#Override
public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
return new MyAsyncUncaughtExceptionHandler();
}
}
with
<beans>
<task:annotation-driven executor="myExecutor" exception-handler="exceptionHandler"/>
<task:executor id="myExecutor" pool-size="7-42" queue-capacity="11"/>
<bean id="asyncBean" class="com.foo.MyAsyncBean"/>
<bean id="exceptionHandler" class="com.foo.MyAsyncUncaughtExceptionHandler"/>
</beans>
SchedulingConfigurer has a similar setup for task:scheduler.
If you want more fine-grained control you can additionally implement the SchedulingConfigurer and/or AsyncConfigurer interfaces.
As belows,
Please notice the pools also,
#Configuration
#EnableScheduling
public class CronConfig implements SchedulingConfigurer{
#Override
public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
taskRegistrar.setScheduler(taskExecutor());
}
#Bean(destroyMethod="shutdown")
public Executor taskExecutor() {
return Executors.newScheduledThreadPool(10);
}
}
And for the Asyncs,
#Configuration
#EnableAsync
public class AsyncConfig implements AsyncConfigurer {
#Override
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(5);
executor.setMaxPoolSize(10);
executor.setQueueCapacity(100);
executor.initialize();
return executor;
}
#Override
public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
return new SimpleAsyncUncaughtExceptionHandler();
}
}
Note that #EnableAsync and #EnableScheduling has to be there for this to work.

Categories