com.palantir.giraffe.command

Class ExecutionSystems

java.lang.Object

com.palantir.giraffe.command.ExecutionSystems

public final class ExecutionSystems
extends Object

Factory methods for execution systems.

The first invocation of any method in this class triggers loading of the default execution system provider, identified by the URI exec:///. If loading this provider fails for any reason, an unspecified error is thrown.

The first invocation of ExecutionSystemProvider.installedProviders() from either newExecutionSystem or getExecutionSystem triggers loading of all installed providers. This loading process is described by ExecutionSystemProvider.

This class also defines a factory method that accepts a ClassLoader, enabling loading of providers from non-standard locations. The class loader is only used if no suitable provider is found using the default methods.

Method Summary

Modifier and Type	Method and Description
static void	closeAfterCompletion(ExecutionSystem es, CommandExitLatch listener) Blocks the registration of any new futures on the ExecutionSystemShutdownListener.
static void	closeAfterCompletion(ExecutionSystem es, CommandFuture commandFuture) Closes any connections the ExecutionSystem uses to execute commands after the CommandFuture finishes, even if other commands are still executing over the connections.
static ExecutionSystem	getDefault() Returns the default execution system for the local machine.
static ExecutionSystem	getExecutionSystem(URI uri) Gets an existing execution system with the specified URI.
static ExecutionSystem	newExecutionSystem(URI uri, Map<String,?> env) Creates a new execution system for the specified URI.
static ExecutionSystem	newExecutionSystem(URI uri, Map<String,?> env, ClassLoader loader) Creates a new execution system for the specified URI.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getDefault

public static ExecutionSystem getDefault()

Returns the default execution system for the local machine.

getExecutionSystem

public static ExecutionSystem getExecutionSystem(URI uri)

Gets an existing execution system with the specified URI.

Parameters:

uri - the URI of the desired system

Throws:

ExecutionSystemNotFoundException - if there is no execution system with the given URI

newExecutionSystem

public static ExecutionSystem newExecutionSystem(URI uri,
                                                 Map<String,?> env)
                                          throws IOException

Creates a new execution system for the specified URI. The number of execution systems with a given URI that may open at the same time is implementation dependent.

Parameters:

uri - the URI of the desired system

env - a map of implementation-specific parameters required to create the system

Returns:

a new ExecutionSystem

Throws:

ExecutionSystemAlreadyExistsException - if an execution system with the specified URI already exists and the implementation forbids duplicate systems

IOException - is an I/O error occurs while creating and opening the execution system

newExecutionSystem

public static ExecutionSystem newExecutionSystem(URI uri,
                                                 Map<String,?> env,
                                                 ClassLoader loader)
                                          throws IOException

Creates a new execution system for the specified URI. The number of execution systems with a given URI that may open at the same time is implementation dependent.

Parameters:

uri - the URI of the desired system

env - a map of implementation-specific parameters required to create the system

loader - the ClassLoader to search for providers if no matching one is found in the default class loader

Returns:

a new ExecutionSystem

Throws:

ExecutionSystemAlreadyExistsException - if an execution system with the specified URI already exists and the implementation forbids duplicate systems

IOException - is an I/O error occurs while creating and opening the execution system

closeAfterCompletion

public static void closeAfterCompletion(ExecutionSystem es,
                                        CommandFuture commandFuture)

Closes any connections the ExecutionSystem uses to execute commands after the CommandFuture finishes, even if other commands are still executing over the connections. This does nothing when called on local command futures.

Parameters:

commandFuture - the command future corresponding to an asynchronous command

closeAfterCompletion

public static void closeAfterCompletion(ExecutionSystem es,
                                        CommandExitLatch listener)

Blocks the registration of any new futures on the ExecutionSystemShutdownListener. Queues a shutdown of the ExecutionSystem, closing any connections used to execute commands. Any non-registered commands still executing will be terminated.