The standard execution of a run action goes through the following steps:

• The user selects a run configuration (for example, by choosing one from the run configurations combobox) and an executor (for example, by pressing a toolbar button created by the executor).
• The program runner that will actually execute the process is selected, by polling all registered program runners and asking whether they can run the specified run profile with the specified executor ID.
• The ExecutionEnvironment object is created. This object aggregates all the settings required to execute the process, as well as the selected ProgramRunner.
• ProgramRunner.execute() is called, receiving the executor and the execution environment.

Implementations of ProgramRunner.execute() go through the following steps to execute the process:

• RunProfile.getState() method is called to create a RunProfileState object, describing a process about to be started. At this stage, the command line parameters, environment variables and other information required to start the process is initialized.
• RunProfileState.execute() is called. It starts the process, attaches a ProcessHandler to its input and output streams, creates a console to display the process output, and returns an ExecutionResult object aggregating the console and the process handler.
• The RunContentBuilder object is created and invoked to display the execution console in a tab of the Run or Debug toolwindow.

Executor

The Executor interface describes a specific way of executing any possible run configuration.

The three default executors provided by the IntelliJ Platform by default are Run, Debug and Run with Coverage. Each executor gets its own toolbar button, which starts the selected run configuration using this executor, and its own context menu item for starting a configuration using this executor.

As a plugin developer, you normally don't need to implement the Executor interface. However, it can be useful, for example, if you're implementing a profiler integration and want to provide the possibility to execute any configuration with profiling.

Running a process

The RunProfileState interface comes up in every run configuration implementation as the return value RunProfile.getState(). It describes a process which is ready to be started and holds the information like the command line, current working directory, and environment variables for the process to be started. (The existence of RunProfileState as a separate step in the execution flow allows run configuration extensions and other components to patch the configuration and to modify the parameters before it gets executed.)

The standard base class used as implementation of RunProfileState is CommandLineState. It contains the logic for putting together a running process and a console into an ExecutionResult, but doesn't know anything how the process is actually started. For starting the process, it's best to use the GeneralCommandLine class, which takes care of setting up the command line parameters and executing the process.

Alternatively, if the process you need to run is a JVM-based one, you can use the JavaCommandLineState base class. It knows about the command line parameters of the JVM and can take care of details like calculating the classpath for the JVM.

To monitor the execution of a process and capture its output, the OSProcessHandler class is normally used. Once you've created an instance of OSProcessHandler from either a command line or a Process object, you need to call the startNotify() method to start capturing its output. You may also want to attach a ProcessTerminatedListener to the OSProcessHandler, so that the exit status of the process will be displayed in the console.

Displaying the process output

If you're using CommandLineState, a console view will be automatically created and attached to the output of the process. Alternatively, you can arrange this yourself:

• TextConsoleBuilderFactory.createBuilder(project).getConsole() creates a ConsoleView instance
• ConsoleView.attachToProcess() attaches it to the output of a process.

If the process you're running uses ANSI escape codes to color its output, the ColoredProcessHandler class will parse it and display the colors in the IntelliJ console.

Console filters allow you to convert certain strings found in the process output to clickable hyperlinks. To attach a filter to the console, use CommandLineState.addConsoleFilters() or, if you're creating a console manually, TextConsoleBuilder.addFilter().

Two common filter implementations you may want to reuse are RegexpFilter and UrlFilter.

Starting a run configuration from code

If you have an existing run configuration that you need to execute, the easiest way to do so is to use ProgramRunnerUtil.executeConfiguration(). The method takes a Project, a RunnerAndConfigurationSettings, as well as an Executor. To get the RunnerAndConfigurationSettings for an existing configuration, you can use, for example, RunManager.getConfigurationSettings(ConfigurationType). As the last parameter, you normally pass either DefaultRunExecutor.getRunExecutorInstance() or DefaultDebugExecutor.getDebugExecutorInstance().