# Interface BuildLauncher

All Superinterfaces:
  `ConfigurableLauncher<BuildLauncher>, LongRunningOperation`

public interface BuildLauncher extends ConfigurableLauncher<BuildLauncher>
A `BuildLauncher` allows you to configure and execute a Gradle build.

Instances of `BuildLauncher` are not thread-safe. You use a `BuildLauncher` as follows:

- Create an instance of `BuildLauncher` by calling `ProjectConnection.newBuild()`.
- Configure the launcher as appropriate.
- Call either `run()` or `run(ResultHandler)` to execute the build.
- Optionally, you can reuse the launcher to launch additional builds.

Example:

    ProjectConnection connection = GradleConnector.newConnector()
       .forProjectDirectory(new File("some-folder"))
       .connect();

    try {
       BuildLauncher build = connection.newBuild();

       //select tasks to run:
       build.forTasks("clean", "test");

       //include some build arguments:
       build.withArguments("-i", "--project-dir", "some-project-dir");

       //configure the standard input:
       build.setStandardInput(new ByteArrayInputStream("consume this!".getBytes()));

       //in case you want the build to use java different than default:
       build.setJavaHome(new File("/path/to/java"));

       //if your build needs crazy amounts of memory:
       build.setJvmArguments("-Xmx2048m", "-XX:MaxPermSize=512m");

       //if you want to listen to the progress events:
       ProgressListener listener = null; // use your implementation
       build.addProgressListener(listener);

       //kick the build off:
       build.run();
    } finally {
       connection.close();
    }

If the target Gradle version is >=6.8 then you can use `BuildLauncher` to execute tasks from included builds. You can target tasks from included builds by specifying the task identity path (i.e. `':included-build-name:subproject-name:taskName'`).

Since:
  1.0-milestone-3

- ## Method Summary

  Modifier and Type
  Method
  Description
  `BuildLauncher`
  `forLaunchables(Iterable<? extends Launchable> launchables)`
  Sets the launchables to execute.
  `BuildLauncher`
  `forLaunchables(Launchable... launchables)`
  Sets the launchables to execute.
  `BuildLauncher`
  `forTasks(Iterable<? extends Task> tasks)`
  Sets the tasks to be executed.
  `BuildLauncher`
  `forTasks(String... tasks)`
  Sets the tasks to be executed.
  `BuildLauncher`
  `forTasks(Task... tasks)`
  Sets the tasks to be executed.
  `void`
  `run()`
  Executes the build, blocking until it is complete.
  `void`
  `run(ResultHandler<? super Void> handler)`
  Launches the build.

  ### Methods inherited from interface ConfigurableLauncher

  `addArguments, addArguments, addJvmArguments, addJvmArguments, addProgressListener, addProgressListener, addProgressListener, addProgressListener, setColorOutput, setEnvironmentVariables, setJavaHome, setJvmArguments, setJvmArguments, setStandardError, setStandardInput, setStandardOutput, withArguments, withArguments, withCancellationToken, withDetailedFailure, withSystemProperties`

- ## Method Details

  - ### forTasks

    BuildLauncher forTasks(String... tasks)
    Sets the tasks to be executed. If no tasks are specified, the project's default tasks are executed.
    Parameters:
      `tasks` - The paths of the tasks to be executed. Relative paths are evaluated relative to the project for which this launcher was created.
    Returns:
      this
    Since:
      1.0-milestone-3

  - ### forTasks

    BuildLauncher forTasks(Task... tasks)
    Sets the tasks to be executed. If no tasks are specified, the project's default tasks are executed.

    Note that the supplied tasks do not necessarily need to belong to the project which this launcher was created for.

    Parameters:
      `tasks` - The tasks to be executed.
    Returns:
      this
    Since:
      1.0-milestone-3

  - ### forTasks

    BuildLauncher forTasks(Iterable<? extends Task> tasks)
    Sets the tasks to be executed. If no tasks are specified, the project's default tasks are executed.

    Note that the supplied tasks do not necessarily need to belong to the project which this launcher was created for.

    Parameters:
      `tasks` - The tasks to be executed.
    Returns:
      this
    Since:
      1.0-milestone-3

  - ### forLaunchables

    BuildLauncher forLaunchables(Launchable... launchables)
    Sets the launchables to execute. If no entries are specified, the project's default tasks are executed.
    Parameters:
      `launchables` - The launchables for this build.
    Returns:
      this
    Since:
      1.12

  - ### forLaunchables

    BuildLauncher forLaunchables(Iterable<? extends Launchable> launchables)
    Sets the launchables to execute. If no entries are specified, the project's default tasks are executed.
    Parameters:
      `launchables` - The launchables for this build.
    Returns:
      this
    Since:
      1.12

  - ### run

    void run() throws GradleConnectionException, IllegalStateException
    Executes the build, blocking until it is complete.
    Throws:
      `UnsupportedVersionException` - When the target Gradle version does not support build execution.
      `UnsupportedOperationConfigurationException` - When the target Gradle version does not support some requested configuration option such as `ConfigurableLauncher.withArguments(String...)`.
      `UnsupportedBuildArgumentException` - When there is a problem with build arguments provided by `ConfigurableLauncher.withArguments(String...)`.
      `BuildException` - On some failure executing the Gradle build.
      `BuildCancelledException` - When the operation was cancelled before it completed successfully.
      `GradleConnectionException` - On some other failure using the connection.
      `IllegalStateException` - When the connection has been closed or is closing.
    Since:
      1.0-milestone-3

  - ### run

    void run(ResultHandler<? super Void> handler) throws IllegalStateException
    Launches the build. This method returns immediately, and the result is later passed to the given handler.

    If the operation fails, the handler's `ResultHandler.onFailure(GradleConnectionException)` method is called with the appropriate exception. See `run()` for a description of the various exceptions that the operation may fail with.

    Parameters:
      `handler` - The handler to supply the result to.
    Throws:
      `IllegalStateException` - When the connection has been closed or is closing.
    Since:
      1.0-milestone-3