Run/debug configurations

IntelliJ IDEA uses run/debug configurations to run, debug, and test applications. A run/debug configuration represents a set of startup properties, such as VM options or JRE, that are used to run the program.

There are two types of run/debug configurations:

Temporary – created for you when you are running a class that does not have a permanent configuration. It provides the bare minimum that allows a class with the main() method to run. Temporary configurations are deleted when their number exceeds the maximum.
Permanent – created explicitly from a template or by saving a temporary configuration. Permanent configurations remain as part of your project until you remove them.

Permanent configurations have opaque icons while the icons of temporary configurations are semi-transparent.

Whenever you perform run, debug, or test operations, IntelliJ IDEA either uses an existing run/debug configuration or creates a new temporary one.

Change the maximum number of temporary run/debug configurations

By default, only 5 temporary run/debug configurations are allowed per project. When the limit is exceeded, the oldest temporary run/debug configuration is replaced by the new one. To change the limit:

From the main menu, select Run | Edit Configurations. Alternatively, press Alt+Shift+F10, then 0.
From the list, select Templates, then in the right-hand pane, configure the Temporary configurations limit parameter.

Create permanent run/debug configurations

IntelliJ IDEA provides the following ways to create a permanent run/debug configuration:

When there is an executable class or method, you can create a permanent run/debug configuration right from the editor.
Save a temporary run/debug configuration.
Create from a template or copy an existing configuration.

Create a permanent run/debug configuration from an executable method or class

Place the caret at the declaration of an executable method or class (for example a class with the main() method or a test suite) and press Alt+Enter. IntelliJ IDEA creates a permanent run/debug configuration of the corresponding type.
Set up the run/debug configuration parameters. For the detailed description of the template, see List of run/debug configurations.

Save a temporary configuration as permanent

Select the temporary configuration in the run/debug configuration switcher and then click Save Configuration.

Create a run/debug configuration from a template

IntelliJ IDEA provides run/debug configuration templates for different languages, tools, and frameworks. The list of available templates varies depending on the installed/bundled plugins.

From the main menu, select Run | Edit Configurations. Alternatively, press Alt+Shift+F10, then 0.
In the Run/Debug Configuration dialog, click on the toolbar or press Alt+Insert. The list shows the run/debug configuration templates. Select Application.
Specify the run/debug configuration name in the Name field. This name will be shown in the list of the available run/debug configurations.
In the Build and run section, specify the following parameters:
- SDK – SDK that will be used for compiling and running your program.
- Main class – the main class defines the entry point of your application. For a class to be used as main, it should contain the public static void main(String[] args) method.
- Program arguments – the command-line arguments to be passed to your application. At runtime, they will be available as strings in the args array. If an argument has spaces inside, enclose it in double quotes, for example: arg1 arg2 "long argument".
Most of the fields have the Expand and Macros options. Expand facilitates editing when the field gets too long. Macros spare you the tedious work of inserting and maintaining parameters that may change over time.
If you want to fine-tune the way your application should be launched, click Modify options to access more advanced run/debug configuration features. When you select an item, it is added to the dialog. Similarly, you can remove unused options.
The following options are available:
- Allow multiple instances – select if you want to allow multiple instances of this program to run at the same time. If this option is disabled, attempting to re-run the application will terminate the active session.
- Environment variables – specify the environment variables for the process as key-value pairs and separate them with semicolons, for example, HOME=/home/me.user;MY_APP_DATA=/home/me.user/appdata. You can override system variables as well as define your custom ones.
  If the line gets too long, click Edit environment variables . A separate dialog opens where you can manage variables in a table-like view, copy/paste them, and so on.
- Redirect input – allows you to take program input from a file instead of the console.
- Do not build before run – select to run the program straight away without launching the build process.
- Add VM options – specify the VM options for running the application. Options are separated using spaces. If an option has spaces inside, enclose it in double quotes. If double quotes is a part of an option, escape them using backslash, for example, -Dsome_option=\"value\". Also, you can pass environment variables to an option, for example, -Dsome_option=${ENVIRONMENT_VARIABLE}.
- Use classpath of module – the module whose classpath will be used. The classpath specified in VM options takes precedence over this one.
- Shorten command line – specifies the command line shortener. Use this option when the program wouldn't launch because the classpath exceeds the limit imposed by the OS. You can pass the classpath to a temporary JAR, a text file, or use the default from idea/workspace.xml (for legacy projects).
- Logs – for information on setting up logging, refer to View logs.
- Code coverage options – for information on setting up coverage, refer to Configure coverage.
- Before launch – define whether you want to perform any specific actions before launching the application, for example, compile the modified sources or run an Ant or Maven script.
Apply the changes and close the dialog.

If you are working in a team, you might want to share your run/debug configurations so that your teammates could run the application using the same configuration or enable them to remotely attach to the process you are running.

For these purposes, IntelliJ IDEA provides a mechanism to store your run/debug configurations as project files and share them through VCS. The same mechanism can also be used when you want to send your configuration as a file to someone else. This saves a lot of time as run/debug configurations sometimes get sophisticated, and keeping them in sync manually would be tedious and error-prone.

Go to the properties of the run/debug configuration you want to share (Run | Edit Configurations ), enable the Store as project file option, and specify the location where the file will be stored.
If compatibility with IntelliJ IDEA 2019.3 and earlier is required, store the file in the default location.

To learn how to use version control systems in IntelliJ IDEA, refer to the Version control topic.

Run/debug configuration templates

For a run/debug configuration of a particular type, you can set up the default values for one or more parameters and save them as a template. In this case, the next time when you create a new configuration of that type, the corresponding fields of the dialog will already contain the specified values.

Configure the default values for a template

From the main menu, select Run | Edit Configurations. Alternatively, press Alt+Shift+F10, then 0.
In the left-hand pane of the run/debug configuration dialog, expand the Templates node and select the desired configuration type. The corresponding configuration template appears in the right-hand pane.
Specify the desired parameters and click Apply to save the template.

Compound run/debug configurations

Suppose you would like to launch multiple run/debug configurations simultaneously. For example, you may want to run a sequence of test configurations, or run configurations for JavaScript and HTML files in one go. You can configure this behavior with a compound run/debug configuration.

When you run or debug your code using a compound configuration, you actually launch a sequence of configurations in the order they are listed.

Create a compound run/debug configuration

From the main menu, select Run | Edit Configurations. Alternatively, press Alt+Shift+F10, then 0.
In the Run/Debug Configurations dialog, click or press Alt+Insert, then select Compound.
Specify the run/debug configuration name in the Name field. This name will be shown in the list of the available run/debug configurations.
To include a new run/debug configuration into the compound configuration, click Add and select the desired one from the list.
Apply the changes.

Run/debug configuration folders

When there are many run/debug configurations of the same type, you can group them in folders so they become easier to distinguish visually.

Once grouped, the run/debug configurations appear in the list under the corresponding folders.

Create a folder for run/debug configurations

From the main menu, select Run | Edit Configurations. Alternatively, press Alt+Shift+F10, then 0.
In the Run/Debug Configurations, select a configuration type and click on the toolbar. A new empty folder for the selected type is created.
Specify the folder name in the text field to the right or accept the default name.
Select the desired run/debug configurations and move them under the target folder.
Apply the changes. If a folder is empty, it will not be saved.

When you no longer need a folder, you can delete it Delete. The run/debug configurations grouped under this folder will be moved under the root of the corresponding run/debug configuration type.

Last modified: 23 April 2021