You can set breakpoints in your code in a number of ways. The most straightforward way is to select a line in your Java code and double-click on the gray area to the left of the line. This sets a breakpoint before the execution of that line. The debugger will suspend execution when it reaches that line, allowing you to inspect variable values and results of expressions, either as defined in the code or created by you in real-time. These expressions can also be used in conditions for breakpoints.

You can set breakpoints on particular Java exceptions, on particular line numbers, on particular method calls, on conditions such as after a certain number of hits on a particular statement, and so on.

The Breakpoints view allows you to view and control all your currently defined breakpoints. After execution reaches a breakpoint, you can control process execution by stepping forwards or backwards through your code execution, or by simply resuming execution until the next breakpoint or until your program terminates.

See the Eclipse online help for detailed information on this view.