Java Debugging in Eclipse by Dr. Bun Yue Professor of Computer Science CSCI 3333 Data Structures

General Resources  Like other IDE, Eclipse includes a good debugger for Java.  Allows developers to control program execution for investigation.  p: check the section on debugging. p

Java Editor  The editor already provides assistance in program development and debugging.

Example

Perspective

Debugging  Likes solving mystery and puzzles, CSI, etc.  You need to have: 1. Domain knowledge 2. Reasoning 3. Investigating and looking for clues 4. Making and testing hypothesis  A debugger can help in (3) and (4).

Java Debugging  To debug a Java program, use one of the following: the debug button Run > Debug As > Java Application After confirmation, a debug perspective (view) is open. You can check variable values during program suspension by breakpoints.

Breakpoints  Can be used to suspend program execution.  Developers can then check variable values.  Can be disabled.

Example

Variable view

Actions after halted  Examples: Step into, Skip all breakpoints, Step Return, drop to frame, etc.

Method breakpoint

Watchpoint  A watchpoint is used to watch a variable.  The debugger halts when the variable is accessed.  You can toggle a watchpoint on a variable by right-clicking the declaration line of the variable.

Hit Count

More tips  More features and tips from java/top-10-java-debugging-tips- with-eclipse/. E.g. java/top-10-java-debugging-tips- with-eclipse/ Watch points Conditional breakpoints …  Video tutorial: t/debugger.html t/debugger.html

More tutorial  ipseDebugging/article.html ipseDebugging/article.html

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