To get a list of class names, a list of variable methods, etc. From source file using eclipse plugin

Hello everyone. I am new to developing eclipse plugins. Actually never wrote. I want to develop a plugin for a plugin before I just want to make sure that it can be implemented below the specified functions. I must have ui buton / interface on click to get a list of class variables present in the active source file (.java) . And I have to be able to compare this class variable or the name methods again refer to some other lines, etc. Also I need to print somethimg based on these comparisons in the console. Is it possible to do this? Is it possible to get a list of classes of methods and varibales from the source file? Is the same possible for C CPP source files?

Thanks in advance

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