Debugging

• Debugging
  • Overview
  • General debugging steps
• Breakpoints
• Using Breakpoints
• Configuring Debugger Options
• Starting the Debugger Session
• Pausing and Resuming the Debugger Session
• Reloading Classes
• Examining Suspended Program
• Exploring Frames
• Customizing Views
• Finding the Current Execution Point
• Stepping Through the Program
• Monitoring the Debug Information
• Inline Debugging
• Attaching to Local Process
• Tutorial. Debugging with Chronon

Overview

This section describes the procedures that are common for various types of applications.

For details on debugging applications in the supported frameworks, refer to Language and Framework - Specific Guidelines.

IntelliJ IDEA provides a full range of facilities for debugging your source code:

• Breakpoints in Java.
• Breakpoints in JavaScript.
• Customizable breakpoint properties: conditions, pass count, etc.
• Frames, variables, and watches views in the debugger UI.
• Runtime evaluation of expressions.

General debugging steps

1. Configure the dependencies and libraries to be passed to the compiler and generate the debugging information.
2. Configure common debugger behavior, including stepping speed, class reloading policy, or scrolling of the editor canvas.
3. Configure the debugger options.
4. To debug CoffeeScript, TypeScript, and Dart code, you need source maps generated in addition to the JavaScript code.

   Source maps set the correspondence between lines in your original code and in the generated JavaScript code, otherwise your breakpoints will not be recognised and processed correctly.

   JavaScript and source maps are generated by transpiling the original code manually using the File Watcher of the corresponding type (CoffeeScript, TypeScript, or Dart). After that, you can debug the output JavaScript code.

   For details, see Using File Watchers, Transpiling CoffeeScript to JavaScript, and Transpiling TypeScript to JavaScript.

5. Define a run/debug configuration for the application to be debugged.
6. Create breakpoints in the source code.
7. Launch a debugging session.
8. Pause or resume the debugging session as required.
9. During the debugger session, step through the breakpoints, evaluate expressions, change values on-the-fly , examine suspended program, explore frames, set watches , reload classes, and customize views .

After you've started a debug session, the icon that marks the Debug tool window toggles to to indicate that the debug process is active.

If you want to see a list of all currently running applications, select Run | Show Running List from the main menu. A popup listing all active applications will be displayed in the top-right corner of the editor.

Note that IntelliJ IDEA lets you debug decompiled code in the same way as your normal source files, provided that it contains line number attributes.