Object interaction - Objects First with Java: A Practical Introduction Using BlueJ - page 86

Figure 3.5
A breakpoint
in the BlueJ editor
Once you have set the breakpoint, invoke the printNextMailItem method on Juan's mail client.
The editor window for the MailClient class and a debugger window will pop up (Figure 3.6).
Along the bottom of the debugger window are some control buttons. They can be used to con-
tinue or interrupt the execution of the program. (For a more detailed explanation of the debug-
ger controls, see Appendix F.)
On the right-hand side of the debugger window are three areas for variable display, titled static
variables , instance variables , and local variables. We will ignore the static-variable area for
now. We will discuss static variables later, and this class does not have any.
Figure 3.6
The debugger window,
execution stopped
at a breakpoint