Debugging Techniques

Debugging is the art of finding and resolving defects or problems within a computer program.

Common Debugging Strategies

1. Print Debugging: Using System.out.println to trace the flow and variable values. Simple but can clutter code.
2. Using a Debugger: Modern IDEs like IntelliJ IDEA and Eclipse have powerful built-in debuggers.
   • Breakpoints: Pause execution at a specific line.
   • Step Over: Execute the current line and move to the next.
   • Step Into: Go inside the method call at the current line.
   • Watch Variables: Monitor the values of specific variables in real-time.

Advanced Debugging

Conditional Breakpoints

You can set a breakpoint to trigger ONLY when a specific condition is met (e.g., i == 500). This is huge for debugging loops!

Remote Debugging

Allows you to debug a Java application running on a different server. You connect your IDE to the remote process using a specific port.

Reading Stack Traces

A stack trace shows the call stack at the moment an exception occurred. It is your best friend when debugging crashes.

Exception in thread "main" java.lang.NullPointerException
    at com.example.MyApp.processData(MyApp.java:15)
    at com.example.MyApp.main(MyApp.java:5)