spring-boot-asynchron-rest-service

JDK VERSION : JDK 11 - AMAZON CORRETTO

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Maven build plugins for JDK 11

  <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.0</version>
                <configuration>
                    <release>11</release>
                    <source>11</source>
                    <target>11</target>
                </configuration>
            </plugin>
   </plugins>

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Configuration

• @EnableAsync and i want to use AsyncConfigurer implementation

    
    @Configuration
    @EnableAsync
    @ComponentScan(basePackages = "tr.salkan.code.java.web.async")
    @ConfigurationProperties("task.profile")
    public class ServiceAsyncConfig implements AsyncConfigurer {
    

• Define ThreadPoolTaskExecutor with corePoolSize,maxPoolSize and queueCapacity

    
        @Bean(name="serviceAsyncExecutor")
        public TaskExecutor smsWorkExecutor() {
        ThreadPoolTaskExecutor threadPoolTaskExecutor = new ThreadPoolTaskExecutor();
        threadPoolTaskExecutor.setThreadNamePrefix("Async-");
        threadPoolTaskExecutor.setCorePoolSize(srvCorePoolSize);
        threadPoolTaskExecutor.setMaxPoolSize(srvMaxPoolSize);
        threadPoolTaskExecutor.setKeepAliveSeconds(srvKeepAliveSecond);
        threadPoolTaskExecutor.setWaitForTasksToCompleteOnShutdown(true);
        threadPoolTaskExecutor.setQueueCapacity(srvQueueCapacity);
        threadPoolTaskExecutor.setRejectedExecutionHandler(new ServiceExecutionHandlerImpl());
        threadPoolTaskExecutor.initialize();
        return threadPoolTaskExecutor;
    }
    

• if task is fill up -> using RejectedExecutionHandler

    
    public class ServiceExecutionHandlerImpl implements RejectedExecutionHandler {

        @Override
        public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {

            try {
                executor.getQueue().put(r);
            }
            catch (InterruptedException e) {

                System.out.println("Service Thread RejectedExecutionHandler"  + e.getMessage());

                throw new RejectedExecutionException("Service Thread RejectedExecutionHandler", e);
            }

        }
    }
    

• catch UncaughtException -> using AsyncUncaughtExceptionHandler

      @Override
      public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
          return new ServiceUncaughtExceptionHandler();
      }
      
      public class ServiceUncaughtExceptionHandler implements AsyncUncaughtExceptionHandler {
      
      
          ...
      
      }
      

• Define CompleTableFuture and exceptionally feature (if you want handle() function)

              CompletableFuture<ResponseObject> p1 = processModul1Component.makeProcess1(requestObject)
                      .exceptionally(e -> {
  
                              System.out.println("p1 except : " + e.getMessage());
                              ResponseObject responseObject = new ResponseObject();
                              responseObject.setModul(ProcessModulEnum.MODUL1);
                              responseObject.setPersonList(new ArrayList<>());
  
                              return responseObject;
                      });
                      

  • Defined asynchron running function (Return CompleTableFuture )

        @Async("serviceAsyncExecutor")
        public CompletableFuture<ResponseObject> makeProcess1(RequestObject requestObject) {
        
            ...
    
            return CompletableFuture.completedFuture(responseObject);
        
        }

    • Blocking thread until all CompletableFutures is done ( .join() )

        // blocking code until p1,p2,p3 completablefuture is done
        CompletableFuture.allOf(p1, p2, p3).join();
        
        //if done, running below code
        other codes

    • Get Object from Completablefuture ( .get() )

            
             try {
      
                  ResponseObject r1 = p1.get();
                  ResponseObject r2 = p2.get();
                  ResponseObject r3 = p3.get();
                   
              } catch (InterruptedException e) {
                  e.printStackTrace();
              } catch (ExecutionException e) {
                  e.printStackTrace();
              }
      

      ---

      Other Configuration

      • Define LocaleResolver and ReloadableResourceBundleMessageSource configuration to read messages_tr_TR

      • Define ExceptionHandlerExceptionResolver class extending with @ControllerAdvice

      • Define custom @JsonSerializer and @JsonDeserializer

          @JsonDeserialize(using = LocalDateTimeDeserializer.class)
          @JsonSerialize(using = LocalDateTimeSerializer.class)
          private LocalDateTime processStartTime;
      
          @JsonSerialize(using = CustomGenericSerializer.class)
          @JsonDeserialize(using = CustomGenericDeSerializer.class)
          private EntityExampleObject entityExampleObject;