DeferredResultProcessingInterceptor is used to intercept into DeferredResult processing life-cycle:
package com.logicbig.example;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.async.DeferredResult;
import org.springframework.web.context.request.async.DeferredResultProcessingInterceptor;
public class MyDeferredResultProcessingInterceptor implements
DeferredResultProcessingInterceptor {
@Override
public <T> void beforeConcurrentHandling (NativeWebRequest request,
DeferredResult<T> deferredResult)
throws Exception {
System.out.println("deferredInterceptor#beforeConcurrentHandler called." +
"Thread: " + Thread.currentThread().getName());
}
@Override
public <T> void preProcess (NativeWebRequest request,
DeferredResult<T> deferredResult) throws Exception {
System.out.println("deferredInterceptor#preProcess called." +
"Thread: " + Thread.currentThread().getName());
}
@Override
public <T> void postProcess (NativeWebRequest request,
DeferredResult<T> deferredResult,
Object concurrentResult) throws Exception {
System.out.println("deferredInterceptor#postProcess called." +
"Thread: " + Thread.currentThread().getName());
}
@Override
public <T> boolean handleTimeout (NativeWebRequest request,
DeferredResult<T> deferredResult) throws Exception {
System.out.println("deferredInterceptor#handleTimeout called." +
"Thread: " + Thread.currentThread().getName());
return false;
}
@Override
public <T> void afterCompletion (NativeWebRequest request,
DeferredResult<T> deferredResult) throws Exception {
System.out.println("deferredInterceptor#afterCompletion called." +
"Thread: " + Thread.currentThread().getName());
}
}
package com.logicbig.example;
import org.springframework.web.context.request.async.WebAsyncManager;
import org.springframework.web.context.request.async.WebAsyncUtils;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class MyAsyncHandlerInterceptor extends HandlerInterceptorAdapter {
private static final Object DEFERRED_INTERCEPTOR_KEY = new Object();
@Override
public boolean preHandle (HttpServletRequest request,
HttpServletResponse response,
Object handler) throws Exception {
System.out.println("interceptor#preHandle called." +
" Thread: " + Thread.currentThread()
.getName());
WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(request);
asyncManager.registerDeferredResultInterceptor(DEFERRED_INTERCEPTOR_KEY,
new MyDeferredResultProcessingInterceptor());
return true;
}
@Override
public void postHandle (HttpServletRequest request,
HttpServletResponse response,
Object handler,
ModelAndView modelAndView) throws Exception {
System.out.println("interceptor#postHandle called." +
"Thread: " + Thread.currentThread()
.getName());
}
@Override
public void afterCompletion (HttpServletRequest request,
HttpServletResponse response,
Object handler, Exception ex) throws Exception {
System.out.println("interceptor#afterCompletion called Thread.: " +
Thread.currentThread()
.getName());
}
@Override
public void afterConcurrentHandlingStarted (HttpServletRequest request,
HttpServletResponse response,
Object handler) throws Exception {
System.out.println("interceptor#afterConcurrentHandlingStarted called. " +
"Thread: " + Thread.currentThread()
.getName());
}
}
package com.logicbig.example;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.context.request.async.DeferredResult;
@Controller
public class MyWebController {
@RequestMapping("/")
@ResponseBody
public DeferredResult<String> handleTestRequest () {
System.out.println("controller#handler called. Thread: " +
Thread.currentThread()
.getName());
final DeferredResult<String> deferredResult = new DeferredResult<>();
new Thread(() -> {
System.out.println("controller-deferred#async task started. Thread: " +
Thread.currentThread()
.getName());
try {
Thread.sleep(300);
} catch (InterruptedException e) {
e.printStackTrace();
}
deferredResult.setResult("test async result");
System.out.println("controller-deferred#async task finished");
}).start();
System.out.println("controller#handler finished");
return deferredResult;
}
}
package com.logicbig.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
public class Main {
public static void main (String[] args) {
SpringApplication.run(BootApplication.class, args);
}
@SpringBootApplication
public static class BootApplication extends WebMvcConfigurerAdapter {
@Override
public void addInterceptors (InterceptorRegistry registry) {
registry.addInterceptor(new MyAsyncHandlerInterceptor());
}
}
}
pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.logicbig.example</groupId>
<artifactId>async-deferred-process-interceptor</artifactId>
<version>1.0-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.2.RELEASE</version>
</parent>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
</project>
