从Web存档执行命令

Question

I included a scheduled job in my WAR file through Quartz and Spring. In case that the scheduled job misses, I have to execute a method Class_A.Method_A() explicitly.

In order to execute the method, I plan to create a static method main() under Class_A so that I can execute jar -cp $CLASSPATH Class_A. However, the class is inside the WAR file, how can I do it?

In addition, the WAR file has its data source and log4j configuration and the method Method_A does database access and logging through them, if I call it on command prompt, is there any conflict?

If calling it through a comamnd prompt is not a good practice, what is a better way? Please help.

Answer 1

Why are you trying to execute 'jar -cp'. This will be a separate jvm execution and hence you will not be able to directly access the resources in the jvm running the web application (this means objects spawned in the jvm's memory space by the web application). [This is answer to your question about conflict/

Please mention what application server on which your web application is running.

Seeing your comment about System Administrator (though I would have mentioned this regardless of this as well). Have you ever heard of ServiceMBeans, you can try them.

Your scenario is a very generalized scenario, where people need to access a particular class (better say instance of the class) running inside a JVM. You certainly need something which loads up along with the application.

You can write a Service MBean to run along (inside) your web application. This would mean you are exposing action. Then you can write a java client to interact with the MBean and make call to its exposed methods.

In case your application server provides authentication for accessing MBeans.

Other option is JMS implementation. Setup a JMSQueue, whose listener will execute the action interacting with the classes of web application. Obviously the listener would load along side web application. EJB implementation would allow you to load the listener via simple ejb xml or through annotations.

Then you write up a separate java code which can send message commands to the JMSQueue. All application server provides the option of authentication.