dk.netarkivet.common.utils
Class ApplicationUtils

java.lang.Object
  dk.netarkivet.common.utils.ApplicationUtils

public abstract class ApplicationUtils
extends java.lang.Object

This class provides functionality for starting applications.

Field Summary

static int	EXCEPTION_WHEN_ADDING_MANAGEMENT System.exit() value for the case where the management registration for the application could not be started.
static int	EXCEPTION_WHEN_ADDING_SHUTDOWN_HOOK System.exit() value for the case where the Shutdown Hook for the application could not be added.
static int	EXCEPTION_WHILE_INSTANTIATING System.exit() value for the case where the application class could not be instantiated.
static int	NO_FACTORY_METHOD System.exit() value for the case where the application does not have a factory method.
static int	WRONG_ARGUMENTS System.exit() value for the case where wrong arguments are given.

Constructor Summary

ApplicationUtils()

Method Summary

static void	dirMustExist(java.io.File dir) Ensure that a directory is available and writable.
static void	startApp(java.lang.Class c, java.lang.String[] args) Starts up an application.
static void	startApp(LifeCycleComponent component) Starts up an LifeCycleComponent.

Methods inherited from class java.lang.Object

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

Field Detail

WRONG_ARGUMENTS

public static final int WRONG_ARGUMENTS

System.exit() value for the case where wrong arguments are given.

See Also:

Constant Field Values

NO_FACTORY_METHOD

public static final int NO_FACTORY_METHOD

System.exit() value for the case where the application does not have a factory method.

See Also:

Constant Field Values

EXCEPTION_WHILE_INSTANTIATING

public static final int EXCEPTION_WHILE_INSTANTIATING

System.exit() value for the case where the application class could not be instantiated.

See Also:

Constant Field Values

EXCEPTION_WHEN_ADDING_SHUTDOWN_HOOK

public static final int EXCEPTION_WHEN_ADDING_SHUTDOWN_HOOK

System.exit() value for the case where the Shutdown Hook for the application could not be added.

See Also:

Constant Field Values

EXCEPTION_WHEN_ADDING_MANAGEMENT

public static final int EXCEPTION_WHEN_ADDING_MANAGEMENT

System.exit() value for the case where the management registration for the application could not be started.

See Also:

Constant Field Values

Constructor Detail

ApplicationUtils

public ApplicationUtils()

Method Detail

startApp

public static void startApp(java.lang.Class c,
                            java.lang.String[] args)

Starts up an application. The applications class must: (i) Have a static getInstance() method which returns a an instance of itself. (ii) Implement CleanupIF. If the class cannot be started and a shutdown hook added, the JVM exits with a return code depending on the problem: 1 means wrong arguments 2 means no factory method exists for class 3 means couldn't instantiate class 4 means couldn't add shutdown hook 5 means couldn't add liveness logger 6 means couldn't add remote management

Parameters:

c - The class to be started.

args - The arguments to the application (should be empty).

startApp

public static void startApp(LifeCycleComponent component)

Starts up an LifeCycleComponent.

Parameters:

component - The component to start.

dirMustExist

public static void dirMustExist(java.io.File dir)

Ensure that a directory is available and writable. Will warn if the directory doesn't already exist (it ought to be created by the install script) and throws a PermissionDenied exception if the directory cannot be created.

Parameters:

dir - A File object denoting a directory.

Throws:

PermissionDenied - if the directory doesn't exist and cannot be created/written to, or if the File object indicates an existing non-directory.