How to enter a value in a JTextField in a third-party application?

Question

Java

Good afternoon.
There is a Java application that was not assembled by me and not even launched by me (but I can slip environment variables or configure Java system parameters).
In one of windows it is necessary to enter some value in JTextField.
Tell me how can this be done?
Tell me, is it possible to do this through the debugger, and if so, how?
Finding the right field for me is not a problem through Frame.getFrames()..., the problem is to be able to do this.

Answer 1

While solved the task so:
1. I find ProcessID, I launch a remote flow (CreateRemoteThread).
2. As the thread code, I specified LoadLibraryA with the path to my DLL.
3. Inside the DLL in DllMain, using JNI, I do defineClass, and then loadClass.
4. Inside my class, I create a URLClassLoader, where I already specify my JAR file, the class from which I then launch.
And it's like being at home there.
I got the method here: xantorohara.blogspot.ru/2007/09/java-code-injectio...