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Look at the Timer class in the swing package.

Do one step at a time. First:
1) create a GUI that displays a value
See the tutorial: Trail: Creating a GUI With JFC/Swing (The Java™ Tutorials)

Break the problem down into two steps:
1) display the values that are to be changed over time
Code that and get it working
When that works, move to:
2) change the display over time

What have you tried?
What problems are you having?
Do you have any specific java programming questions?

Are you asking about how to build a GUI that changes what it displays over time?