ExceptionHandlingXtreamHandler

介绍

提示

ExceptionHandlingXtreamHandler 借鉴于 org.springframework.web.server.handler.ExceptionHandlingWebHandler。

从名称可以看出来，ExceptionHandlingXtreamHandler 本质上是一个 XtreamHandler，前缀 ExceptionHandling 表示该组件具有处理异常的功能。

ExceptionHandlingXtreamHandler 内部维护着一堆 XtreamRequestExceptionHandler 和一个 XtreamHandler(实际上是FilteringXtreamHandler)。

实现比较直观，不再做过多的介绍。下面是源码：

public class ExceptionHandlingXtreamHandler implements XtreamHandler {
    private static final Logger log = LoggerFactory.getLogger(ExceptionHandlingXtreamHandler.class);
    private final XtreamHandler delegateHandler;
    private final List<XtreamRequestExceptionHandler> exceptionHandlers;

    public ExceptionHandlingXtreamHandler(XtreamHandler delegateHandler, List<XtreamRequestExceptionHandler> exceptionHandlers) {
        this.delegateHandler = delegateHandler;

        final List<XtreamRequestExceptionHandler> list = new ArrayList<>();
        list.add(new XtreamRequestExceptionHandler.CheckpointInsertingXtreamRequestExceptionHandler());
        list.addAll(exceptionHandlers);
        this.exceptionHandlers = OrderedComponent.sort(list);
    }

    @Override
    public Mono<Void> handle(XtreamExchange exchange) {
        Mono<Void> completion;
        try {
            completion = this.delegateHandler.handle(exchange);
        } catch (Throwable ex) {
            completion = Mono.error(ex);
        }

        for (XtreamRequestExceptionHandler handler : this.exceptionHandlers) {
            completion = completion.onErrorResume(ex -> {
                final Throwable cause = XtreamWrappedRuntimeException.unwrapIfNecessary(ex);
                return handler.handleRequestException(exchange, cause);
            });
        }

        return completion;
    }
}