How to detect when a variable changes value

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How can I easily detect when a variable changes value? I would like the execution of the program to break on the debugger whenever a specified variable changes value. Right now I'm using Eclipse's debugger.

3 Answers

For a class or instance variable

  1. right-click on the variable in the outline view
  2. select "Toggle Watchpoint"
  3. Then, in the breapkoints view, you can right-click on the resulting entry
  4. select "breakpoint properties"
  5. deselect "Field Access".

I'm not sure about Eclipse, but in IntelliJ IDEA, you can right click on a break point and add the conditions, just like you would in an if statement. Then, the debugger only pauses at the break point if its condition is true.

For instance, in this case it only stops if min == 4.

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