消息路由器

Spring 集成原生提供了专门的路由器类型，包括：spring-doc.cadn.net.cn

与许多其他 DSL 一样IntegrationFlowBuilderEIP 方法、route()method 可以应用任何AbstractMessageRouterimplementation 或者为方便起见，使用String作为 SPEL 表达式或ref-method双。 此外，您还可以配置route()替换为 lambda，并将 lambda 用于Consumer<RouterSpec<MethodInvokingRouter>>. Fluent API 还提供AbstractMappingMessageRouter选项，例如channelMapping(String key, String channelName)对，如下例所示：spring-doc.cadn.net.cn

@Bean
public IntegrationFlow routeFlowByLambda() {
    return IntegrationFlow.from("routerInput")
            .<Integer, Boolean>route(p -> p % 2 == 0,
                    m -> m.suffix("Channel")
                            .channelMapping(true, "even")
                            .channelMapping(false, "odd")
            )
            .get();
}

以下示例显示了一个简单的基于表达式的路由器：spring-doc.cadn.net.cn

@Bean
public IntegrationFlow routeFlowByExpression() {
    return IntegrationFlow.from("routerInput")
            .route("headers['destChannel']")
            .get();
}

这routeToRecipients()method 采用Consumer<RecipientListRouterSpec>，如下例所示：spring-doc.cadn.net.cn

@Bean
public IntegrationFlow recipientListFlow() {
    return IntegrationFlow.from("recipientListInput")
            .<String, String>transform(p -> p.replaceFirst("Payload", ""))
            .routeToRecipients(r -> r
                    .recipient("thing1-channel", "'thing1' == payload")
                    .recipientMessageSelector("thing2-channel", m ->
                            m.getHeaders().containsKey("recipient")
                                    && (boolean) m.getHeaders().get("recipient"))
                    .recipientFlow("'thing1' == payload or 'thing2' == payload or 'thing3' == payload",
                            f -> f.<String, String>transform(String::toUpperCase)
                                    .channel(c -> c.queue("recipientListSubFlow1Result")))
                    .recipientFlow((String p) -> p.startsWith("thing3"),
                            f -> f.transform("Hello "::concat)
                                    .channel(c -> c.queue("recipientListSubFlow2Result")))
                    .recipientFlow(new FunctionExpression<Message<?>>(m ->
                                    "thing3".equals(m.getPayload())),
                            f -> f.channel(c -> c.queue("recipientListSubFlow3Result")))
                    .defaultOutputToParentFlow())
            .get();
}

这.defaultOutputToParentFlow()的.routeToRecipients()definition 允许您设置路由器的defaultOutput作为网关，以继续处理 MAIN FLOW 中不匹配的消息。spring-doc.cadn.net.cn

另请参阅lambda 和Message<?>参数.spring-doc.cadn.net.cn