The debugger has the these windows:
Breakpoints window – Displays the list of current breakpoints.
Calls window – Displays the current call stack.
Classes window – Displays a list of classes currently loaded in the Java VM. In addition, this window displays a list of methods for the currently selected class and a list of static variables for the currently selected class. In this window you can set breakpoints on entry to a method or when a static variable is written.
Connection window – The Connection window is shown when the debugger is started. You can display it again if you wish to disconnect from the database.
Exceptions window – You can set a particular exception on which to break, or choose to break on all exceptions.
Inspection window – Displays current static variables, and allows you to modify them. You can also inspect the value of a Java expression, such as the following:
Expressions using the dot operator
Expressions using subscripts 
Expressions using parentheses, arithmetic, or logical operators.
For example, the following expressions could be used:
x[i].field q + 1 i == 7 (i + 1)*3
Locals window – Displays current local variables, and allows you to modify them.
Status window – Displays messages describing the execution state of the Java VM.