How can I run a method Asynchronously with spring?

Question

The following code is suppose to work Asynchronously but instead it waits for the Async part to finish and then goes. How can I make the blah() method run Asynchronously?

spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans 
    xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:task="http://www.springframework.org/schema/task"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans 
        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/task
        http://www.springframework.org/schema/task/spring-task-3.0.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context-3.0.xsd
    ">

    <!-- Activates @Scheduled and @Async annotations for scheduling -->  
    <task:annotation-driven />

    <bean id="test"
        class="com.spring.test.Test">
</beans>

Test.java

@Path("/test")
public class Test
{
  @GET
  @Path("/test")
  @Produces("text/plain")
  public String tester()
  {
    return "Running...";
  }

  @GET
  @Path("/triggerNew")
  @Produces("text/plain")
  public String triggerNew()
  {
    System.out.println("BEFORE " + new Date() + " BEFORE");

    new Process().blah();

    System.out.println("AFTER " + new Date() + " AFTER");
    return "TRIGGERED";
  }
}

Process.java

  @Component
    public class Process
    {
      @Async
      public void blah()
      {
        try
        {
          Thread.currentThread().sleep(5000);
        }
        catch (InterruptedException e)
        {
          e.printStackTrace(); 
        }
        System.out.println("NEW THREAD " + new Date() + " NEW THREAD");
      }
    }

Solution 1

@Async only works when you annotate Spring-managed beans, not arbitrary classes. You need to define Process as a Spring bean, and then inject it into your controller class, e.g.

<bean id="test" class="com.spring.test.Test">
   <property name="process">
      <bean class="com.spring.test.Process"/>
   </property>
</bean>

---

public class Test {
   private Process process;

   public void setProcess(Process process) {
      this.process = process;
   }

   ...

   public String triggerNew() {  
      process.blah();
   }
}

Solution 2

Alternatively you can execute your task manually with TaskExecutor. Just define executor in the context:

<bean id="taskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor"/>

Than you can execute yor task:

taskExecutor.execute(new Process ());

But in this case your Process class must implement Runnable interface

Comments

[Grammin]

I've updated the code to include @Component, but I don't exactly know how to inject Process.java into my controller?

[Grammin]

I'm getting a Cannot proxy target class because CGLIB2 is not available. Add CGLIB to the class path or specify proxy interfaces. in my spring.xml, any ideas?

[skaffman]

@Grammin: Either add CGLIB to the classpath, or create an interface with the triggerNew method in it, and make Process implement that interface.