/**
 * Encapsulates the state for a build session.
 */
public class BuildSessionState implements Closeable {
    private final GradleUserHomeScopeServiceRegistry userHomeScopeServiceRegistry;
    private final ServiceRegistry userHomeServices;
    private final ServiceRegistry sessionScopeServices;
    private final DefaultBuildSessionContext context;

    public BuildSessionState(GradleUserHomeScopeServiceRegistry userHomeScopeServiceRegistry,

                try (BuildSessionState buildSessionState = new BuildSessionState(userHomeServiceRegistry, crossBuildSessionState, startParameter, requestContext, actionParameters.getInjectedPluginClasspath(), requestContext.getCancellationToken(), requestContext.getClient(), requestContext.getEventConsumer())) {
                    return buildSessionState.run(actionWrapper);
                }
            }

        BuildSessionState buildSessionState = new BuildSessionState(userHomeServices, crossBuildSessionState, startParameter, buildRequestMetaData, ClassPath.EMPTY, new DefaultBuildCancellationToken(), buildRequestMetaData.getClient(), new NoOpBuildEventConsumer());

        StartParameterInternal startParameter = buildDefinition.getStartParameter();
        BuildRequestMetaData buildRequestMetaData = new DefaultBuildRequestMetaData(Time.currentTimeMillis());
        BuildSessionState session = new BuildSessionState(userHomeDirServiceRegistry, crossBuildSessionState, startParameter, buildRequestMetaData, ClassPath.EMPTY, buildCancellationToken, buildRequestMetaData.getClient(), new NoOpBuildEventConsumer());
        try {

    def clientMetadata = Mock(BuildClientMetaData)
    def cancellationToken = Mock(BuildCancellationToken)
    def eventConsumer = Mock(BuildEventConsumer)
    def classPath = ClassPath.EMPTY
    BuildSessionState state

    def setup() {
        _ * userHomeServiceRegistry.getServicesFor(_) >> new DefaultServiceRegistry()
        def services = new DefaultServiceRegistry()

For example, when continuous build is enabled, the session may run the build many times, but when it is disabled, the session will run the build once only.

The build session state is managed by the `BuildSessionState` class.
An instance is created at the start of a Gradle invocation and discarded at the end of that invocation.