C# search child java-window elements

I want to search window's controls by handle in C# code, whenever the other window is a java window.

The following link works on windows application: C# get child handles using FindWindowEx by name and ordinal number

When the searched window is java application window, I don't know how to search it, because "TextBox" in java is not "TextBox" in C#.

How can I search the controls of the other window, whenever the other window is java application window? (By some reflection or any other attitude).