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Before debugging

The debug session starts with the selected run/debug configuration. Note that several debug processes can be launched simultaneously.

When debugging an application in IntelliJ IDEA, keep in mind that

  • If the Make module before running/debugging/reloading option has been selected, IntelliJ IDEA first compiles all modified sources in your project.
  • IntelliJ IDEA proceeds with debugging, if compilation reports no errors.
  • If the code has not been compiled before debugging, the source and class files might be out of sync.
  • If you specify the -classpath option in the VM Options field, the selected module classpath will be overridden.
  • If you debug a JavaScript source, IntelliJ IDEA opens a browser for the HTML file with your script in a separate frame.

Debugging an application

To start debugging an application, do one of the following
  • Select the run/debug configuration to execute, and then do one of the following:
    • Click ../../Shared/run.png icon in the left gutter, and then choose ../../Shared/debug.png.
    • Click ../../Shared/debug.png on the toolbar.
    • Choose Run | Debug on the main menu.
    • Press ⌃D⇧F9⌘F11⌥ F5⇧ F9.
  • Press ⌃⌥D⌥⇧F9⌃⌥D⇧ ⌥ F9⇧ ⌥ F9, select the configuration from the pop-up menu, and press ⏎⏎⏎EnterEnter.

Note that after you've launched a debug session, the ../../Shared/debug.png icon that marks the Debug Tool Window toggles to ../../Shared/active_debug_icon.png to indicate that the debugging process is active.