com.globalmentor.application

Class AbstractApplication

java.lang.Object

com.globalmentor.application.AbstractApplication

All Implemented Interfaces:

Application, com.globalmentor.model.Named<String>, com.globalmentor.net.Resource

public abstract class AbstractApplication
extends Object
implements Application

An abstract implementation of an application that by default is a console application.

Every application provides a default preference node based upon the implementing application class.

Author:

Garret Wilson

Field Summary

Fields inherited from interface com.globalmentor.application.Application

NO_ARGUMENTS

Fields inherited from interface com.globalmentor.net.Resource

URI_PROPERTY_NAME

Constructor Summary

Constructors

Constructor and Description
AbstractApplication(URI uri, String name) URI constructor.
AbstractApplication(URI uri, String name, String[] args) URI and arguments constructor.

Method Summary

Modifier and Type	Method and Description
protected boolean	canExit() Determines whether the application can exit.
boolean	canStart() Checks requirements, permissions, and expirations before starting.
void	displayError(String message) Displays the given error to the user
void	displayError(Throwable throwable) Displays an error message to the user for an exception.
void	exit() Exits the application with no status.
void	exit(int status) Exits the application with the given status.
String[]	getArgs()
com.globalmentor.net.Authenticable	getAuthenticator()
static String	getDisplayErrorMessage(Throwable throwable) Constructs a user-presentable error message based on an exception.
Date	getExpirationDate()
String	getName()
Preferences	getPreferences()
URI	getURI()
void	initialize() Initializes the application.
protected static void	initialize(Application application, String[] args) Initializes the environment for the application.
protected void	performExit(int status) Exits the application with the given status without checking to see if exit should be performed.
static int	run(Application application, String[] args) Starts an application.
void	setAuthenticator(com.globalmentor.net.Authenticable authenticable) Sets the authenticator object used to retrieve client authentication.
protected void	setExpiration(Date newExpirationDate) Sets the expiration date of the application.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.globalmentor.application.Application

main

Constructor Detail

AbstractApplication

public AbstractApplication(URI uri,
                           String name)

URI constructor.

Parameters:

uri - The URI identifying the application.

name - The name of the application.

AbstractApplication

public AbstractApplication(URI uri,
                           String name,
                           String[] args)

URI and arguments constructor.

Parameters:

uri - The URI identifying the application.

name - The name of the application.

args - The command line arguments.

Method Detail

getURI

public URI getURI()

Specified by:

getURI in interface com.globalmentor.net.Resource

getName

public String getName()

Specified by:

getName in interface com.globalmentor.model.Named<String>

getAuthenticator

public com.globalmentor.net.Authenticable getAuthenticator()

Specified by:

getAuthenticator in interface Application

Returns:

The authenticator object used to retrieve client authentication.

setAuthenticator

public void setAuthenticator(com.globalmentor.net.Authenticable authenticable)

Sets the authenticator object used to retrieve client authentication. This version updates the authenticator of the default HTTP client.

Specified by:

setAuthenticator in interface Application

Parameters:

authenticable - The object to retrieve authentication information regarding a client.

See Also:

HTTPClient

getArgs

public String[] getArgs()

Specified by:

getArgs in interface Application

Returns:

The command-line arguments of the application.

getPreferences

public Preferences getPreferences()
                           throws SecurityException

Specified by:

getPreferences in interface Application

Returns:

The default user preferences for this application.

Throws:

SecurityException - Thrown if a security manager is present and it denies RuntimePermission("preferences").

getExpirationDate

public Date getExpirationDate()

Specified by:

getExpirationDate in interface Application

Returns:

The expiration date of the application, or null if there is no expiration.

setExpiration

protected void setExpiration(Date newExpirationDate)

Sets the expiration date of the application.

Parameters:

newExpirationDate - The new expiration date, or null if there is no expiration.

initialize

public void initialize()
                throws Exception

Initializes the application. This method is called after construction but before application execution. This version does nothing.

Specified by:

initialize in interface Application

Throws:

Exception - Thrown if anything goes wrong.

canStart

public boolean canStart()

Checks requirements, permissions, and expirations before starting.

Specified by:

canStart in interface Application

Returns:

true if the checks succeeded.

displayError

public void displayError(Throwable throwable)

Displays an error message to the user for an exception.

Specified by:

displayError in interface Application

Parameters:

throwable - The condition that caused the error.

displayError

public void displayError(String message)

Displays the given error to the user

Specified by:

displayError in interface Application

Parameters:

message - The error to display.

getDisplayErrorMessage

public static String getDisplayErrorMessage(Throwable throwable)

Constructs a user-presentable error message based on an exception. In most cases this is Throwable.getMessage().

Parameters:

throwable - The condition that caused the error.

See Also:

Throwable.getMessage()

run

public static int run(Application application,
                      String[] args)

Starts an application.

Parameters:

application - The application to start.

args - The command line arguments.

Returns:

The application status.

initialize

protected static void initialize(Application application,
                                 String[] args)
                          throws Exception

Initializes the environment for the application.

Parameters:

application - The application to start.

args - The command line arguments.

Throws:

Exception - Thrown if anything goes wrong.

canExit

protected boolean canExit()

Determines whether the application can exit. This method may query the user. If the application has been modified, the configuration is saved if possible. If there is no configuration I/O kit, no action is taken. If an error occurs, the user is notified.

Returns:

true if the application can exit, else false.

exit

public final void exit()

Exits the application with no status. Convenience method which calls exit(int).

Specified by:

exit in interface Application

See Also:

exit(int)

exit

public final void exit(int status)

Exits the application with the given status. This method first checks to see if exit can occur. To add to exit functionality, performExit(int) should be overridden rather than this method.

Specified by:

exit in interface Application

Parameters:

status - The exit status.

See Also:

canExit(), performExit(int)

performExit

protected void performExit(int status)
                    throws Exception

Exits the application with the given status without checking to see if exit should be performed.

Parameters:

status - The exit status.

Throws:

Exception - Thrown if anything goes wrong.