Help me!! i don't know how to debug jni program!!

Question

i have finished a jni program. but when i run the java project, some errors appeared.
for i am sure the errors come from the native method ,i set a breakpoint on the native call and debug the project. for the jni program were written with c++, so when i choose "step into" , it dosen't step into and just report some kinds of error.
i use jbuilder4.0 for java program and vc++6.0 for the native method.
i had try two ways. i try to invoke the JVM in native method but i failed to set the classpath. and i debug the native method , the dll, and link to the java.exe. but there is no place to input my classname when load the java.exe. what the result is some information of java.exe.
can anybody help me??!!!!

Answer 1

Make sure your Active Configuration is set to Debug.
Then make sure you are loading the dll from the Debug directory in your Java application. Set all the Breakpoints etc you want in your DLL, build it.
Start your java application from the command line (you do not need it in debug mode at all if you only want to debug the DLL. Make sure you have some way of causing the App to wait for some interaction so you can do the following.
In your open CV++ project select Build->Start Debugging->Attach to Process. Attach to the process that is the java VM running your App.
The cause your Java app to run normally.
Breakpoints etc will cause the VC++ debugger to be invoked and you can merrily debug to your hearts content.