Java EE应用程序中的Applet访问蓝牙外围设备客户端

Question

I currently have a Java EE application on a server. It is using struts2 and Hibernate. I need to acces to the client computer and search for all the MAC address of the bluetooth peripheral detected by the client computer.

So the problem is : how to access to the client computer ? Do I have to use a Java Applet ? My teacher say that the applet are really sensitive to the version of Java installed on the client computer! That would be a problem if an applet designed for Java 5 would not run with Java 6 !

Is it true? Is there any other solution than the applet ?

Answer 1

how to access to the client computer ? Do I have to use a Java Applet ?

I don't know if it is the only way, but a trusted applet could have a shot at getting the information. I say 'have a shot' in the sense that it is unlikely core Java SE provides the functionality for this task, so you will probably need to look into using natives for each system.

My teacher say that the applet are really sensitive to the version of Java installed on the client computer! That would be a problem if an applet designed for Java 5 would not run with Java 6 !

No, it is the other way around. If an applet is compiled for Java 6, it will not run on Java 5. But an applet designed to run in Java 5 should have no problems running in a version 6 JVM.

As to the problems that arise from that, they are easily solvable:

1. Use deployJava.js for ensuring a particular minimum Java version, and it should handle the 'heavy lifting' of one of:
   1. Checking the user has a suitable minimum JRE and writing an applet element for it.
   2. Helping the user through an upgrade (then going onto 1)
   3. Informing the user why the applet won't work.
2. The same situation applies to any code run on the desktop, whether it is an applet, an app. that runs in the command line, or a desktop app.