me.alidg.errors

Class WebErrorHandlers

java.lang.Object

me.alidg.errors.WebErrorHandlers

public class WebErrorHandlers
extends Object

A factory over WebErrorHandler implementations. The factory would query all the implementations to find an appropriate exception handler to handle a particular exception.

Code to Message Translation

The WebErrorHandlers is also responsible for Error Code to Error Message translation and i18n (RIP SRP!). In order to fulfill this requirement, we need an instance of MessageSource to translate error codes to error messages.

Default Exception Handler

By default, when we couldn't find any WebErrorHandler implementation to handle the exception, we would use the LastResortWebErrorHandler as the default exception handler. If you don't like its exception handling approach, consider passing a valid non-null defaultWebErrorHandler to the constructor.

Author:

Ali Dehghani

See Also:

WebErrorHandler, HandledException, LastResortWebErrorHandler

Constructor Summary

Constructors

Constructor and Description
WebErrorHandlers(org.springframework.context.MessageSource messageSource, List<WebErrorHandler> implementations, WebErrorHandler defaultWebErrorHandler, ExceptionRefiner exceptionRefiner) To initialize the WebErrorHandlers instance with a code-to-message translator, a non-empty collection of WebErrorHandler implementations and an optional fallback error handler.

Method Summary

Modifier and Type	Method and Description
HttpError	handle(Throwable exception, Locale locale) Given any exception, first it would select an appropriate exception handler or falls back to a default handler and then tries to handle the exception using the chosen handler.

Methods inherited from class java.lang.Object

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

Constructor Detail

WebErrorHandlers

public WebErrorHandlers(@NonNull
                        org.springframework.context.MessageSource messageSource,
                        @NonNull
                        List<WebErrorHandler> implementations,
                        @Nullable
                        WebErrorHandler defaultWebErrorHandler,
                        @Nullable
                        ExceptionRefiner exceptionRefiner)

To initialize the WebErrorHandlers instance with a code-to-message translator, a non-empty collection of WebErrorHandler implementations and an optional fallback error handler.

Parameters:

messageSource - The code to message translator.

implementations - Collection of WebErrorHandler implementations.

defaultWebErrorHandler - Fallback web error handler.

exceptionRefiner - Possibly can refine exceptions before handling them.

Throws:

NullPointerException - When one of the required parameters is null.

IllegalArgumentException - When the collection of implementations is empty.

Method Detail

handle

@NonNull
public HttpError handle(@Nullable
                                 Throwable exception,
                                 @Nullable
                                 Locale locale)

Given any exception, first it would select an appropriate exception handler or falls back to a default handler and then tries to handle the exception using the chosen handler. Then would convert the HandledException to its corresponding HttpError.

Parameters:

exception - The exception to handle.

locale - Will be used to target a specific locale while translating the codes to error messages.

Returns:

An HttpError instance containing both error and message combinations and also, the intended HTTP Status Code.