org.jasig.portal.lang
Class ThrowableHelper

java.lang.Object
  org.jasig.portal.lang.ThrowableHelper

public final class ThrowableHelper
extends Object

The ThrowableHelper class defines a set of utility methods for handling common error management operations in a fashion which takes advantage of the J2SDK 1.4 constructs while maintaining J2SDK 1.3 compatibility.

Version:

"$Revision: 19776 $"

Author:

Jan Nielsen

Method Summary

static Throwable	create(Class throwableClass, Class client, String propertyName, String[] args, Throwable cause) Creates the specified Throwable object with the internationalized error code and arguments.
static ThrowableHandler	getDefaultHandler(String className) Returns a constructed instance of the default handler.
static String	getInternationalizedMessage(Class client, String error) Returns an internationalized error message which can be reconstructed into a localized error message with the getLocalizedMessage method call.
static String	getInternationalizedMessage(Class client, String error, String[] objects) Returns an internationalized error message which can be reconstructed into a localized error message with the getLocalizedMessage method call.
static String	getLocalizedMessage(String i18nMessage) Returns the localized error message associated with the specified internationalized error message constructed with the getInternationalizedMessage method.
static String	getLocalizedMessage(String i18nMessage, Locale locale) Returns the localized error message associated with the specified internationalized error message constructed with the getInternationalizedMessage method.
static String	getLocalizedMessage(Throwable throwable) Returns the localized string associated with the argument.
static String	getLocalizedMessage(Throwable throwable, Locale locale) Returns the localized string associated with the argument in the specified locale, if possible.
static void	handle(Class client, String message, String[] objects, Throwable cause) Handles the throwable condition specified in the parameters.
static void	handle(Class client, String message, String[] objects, Throwable cause, ThrowableHandler handler) Handles the throwable condition specified in the parameters.
static void	handle(Throwable cause) Handles the throwable condition specified in the parameter.
static void	initCause(Throwable throwable, Throwable cause) Initizlizes the chained cause of the throwable if possible using the J2SDK 1.4 constructs.

Methods inherited from class java.lang.Object

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

Method Detail

getDefaultHandler

public static final ThrowableHandler getDefaultHandler(String className)

Returns a constructed instance of the default handler. The class name passed to the method must be an implementation of the ThrowableHandler interface and have an accessible default constructor.

Parameters:

className - name of the throwable handler class

Returns:

instance of the specified handler class, or the default error handler

getInternationalizedMessage

public static final String getInternationalizedMessage(Class client,
                                                       String error)

Returns an internationalized error message which can be reconstructed into a localized error message with the getLocalizedMessage method call.

Parameters:

client - class of the client making this call

error - error property name of the error condition

Returns:

internationalized error message

getInternationalizedMessage

public static final String getInternationalizedMessage(Class client,
                                                       String error,
                                                       String[] objects)

Returns an internationalized error message which can be reconstructed into a localized error message with the getLocalizedMessage method call.

Parameters:

client - class of the client making this call

error - error property name of the error condition

objects - string objects which should be stored for the message

Returns:

internationalized error message

Throws:

NullPointerException - if client, or error parameters are null

getLocalizedMessage

public static final String getLocalizedMessage(String i18nMessage)

Returns the localized error message associated with the specified internationalized error message constructed with the getInternationalizedMessage method. The default locale is used.

Parameters:

i18nMessage - internationalized error message

Returns:

localized error message, or null

getLocalizedMessage

public static final String getLocalizedMessage(Throwable throwable)

Returns the localized string associated with the argument.

Parameters:

throwable - object whose message is to be localized

Returns:

localized message associated with Throwable

getLocalizedMessage

public static final String getLocalizedMessage(Throwable throwable,
                                               Locale locale)

Returns the localized string associated with the argument in the specified locale, if possible. If the locale is not supported the default locale message will be returned.

Parameters:

throwable - object whose message is to be localized

locale - locale to localized the message

Returns:

localized message associated with Throwable

getLocalizedMessage

public static final String getLocalizedMessage(String i18nMessage,
                                               Locale locale)

Returns the localized error message associated with the specified internationalized error message constructed with the getInternationalizedMessage method. The locale of for the translation is picked up from the current session.

Parameters:

i18nMessage - internationalized error message

locale - locale to translate the message

Returns:

localized error message, or null

initCause

public static final void initCause(Throwable throwable,
                                   Throwable cause)

Initizlizes the chained cause of the throwable if possible using the J2SDK 1.4 constructs. In a J2SDK pre-1.4 environment, this method does nothing.

Parameters:

throwable - throwable whose cause should be set

cause - throwable which caused the throwable condition

create

public static final Throwable create(Class throwableClass,
                                     Class client,
                                     String propertyName,
                                     String[] args,
                                     Throwable cause)

Creates the specified Throwable object with the internationalized error code and arguments. If the cause object is not null, the specified object's initCause method will be invoked reflectively to enable the standard chaining constructs. The specified error code is an internationalized error property value which must be defined in a resource bundle associated with the client, specificifically the code will perform a ResourceBundle.getBundle( ) to resolve the resource. Invoking this method is equivalent to creating the Throwable with an internationalized message and then invoking ThrowableHelper.initCause, e.g.,:

 Throwable someCause = ...
 
 String i18nMessage = ThrowableHelper.getInternationalizedMessage(
     MyApplication.class,
     "myapplication.some_error_code",
     new String[]{ "32", "1024" }
     );

 IllegalArgumentException iae = new IllegalArgumentException(
     i18nMessage
     );

 ThrowableHelper.initCause(
     iae,
     someCause
     );
 

Parameters:

throwableClass - throwable object to be constructed

client - class file of the client

propertyName - internationalized error code property name defined in the client's resouce bundle

args - arguments for the localized message

cause - cause of the created exception, or null

Returns:

throwable object of the specified type

handle

public static final void handle(Throwable cause)

Handles the throwable condition specified in the parameter. The default handler is used to process this handler.

Parameters:

cause - throwable condition which should be handled

handle

public static final void handle(Class client,
                                String message,
                                String[] objects,
                                Throwable cause)

Handles the throwable condition specified in the parameters. The default handler is used to process this handler.

Parameters:

client - client performing the handling

cause - throwable condition which should be handled

message - associated with handling the error

objects - associated with the error message

handle

public static final void handle(Class client,
                                String message,
                                String[] objects,
                                Throwable cause,
                                ThrowableHandler handler)

Handles the throwable condition specified in the parameters. If the specified handler is null the default handler is used; otherwise, the specified handler is used to process this request.

Parameters:

client - client performing the handling

cause - throwable condition which should be handled

message - associated with handling the error

objects - associated with the error message

handler - which should be executed instead of the default handler