Apache camel 如何使用Apache Camel创建自己的RouteBuilder？

我正在尝试创建自己的RouteBuilder，但出现以下错误：

java.lang.IllegalArgumentException: onException must be defined before any routes in the RouteBuilder
    at org.apache.camel.builder.RouteBuilder.onException(RouteBuilder.java:214)
    at com.mdw360.ttt.mongo.fab.route.ExceptionBuilder.configure(ExceptionBuilder.java:18)
    at org.apache.camel.builder.RouteBuilder.checkInitialized(RouteBuilder.java:322)
    at org.apache.camel.builder.RouteBuilder.configureRoutes(RouteBuilder.java:276)
    at org.apache.camel.builder.RouteBuilder.addRoutesToCamelContext(RouteBuilder.java:262)
    at org.apache.camel.impl.DefaultCamelContext.addRoutes(DefaultCamelContext.java:679)
    at org.apache.camel.test.junit4.CamelTestSupport.doSetUp(CamelTestSupport.java:302)
    at org.apache.camel.test.junit4.CamelTestSupport.setUp(CamelTestSupport.java:217)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.rules.TestWatcher$1.evaluate(TestWatcher.java:55)
    at org.junit.rules.RunRules.evaluate(RunRules.java:20)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:160)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:78)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)

在我的ExceptionBuilder上，我有以下代码：

public class ExceptionBuilder extends RouteBuilder{
    @Override
    public void configure() throws Exception {
        ExceptionProcessor exceptionProcessor = new ExceptionProcessor();
        onException(Exception.class).process(exceptionProcessor);
    }
}

在我的测试中，我发现：

 @Test
    public void testExceptionWhileRouting() throws Exception {
        getMockEndpoint("mock:http").expectedBodiesReceived("Camel rocks");

        getMockEndpoint("mock:http").whenAnyExchangeReceived(new Processor() {
            public void process(Exchange exchange) throws Exception {
                System.out.println("ERROR");
                exchange.setException(new ConnectException("Simulated connection error"));
            }
        });

        template.sendBody("direct:file", "Camel rocks");

        assertMockEndpointsSatisfied();
    }

    @Override
    protected RouteBuilder createRouteBuilder() {
        ExceptionBuilder routeBuilder = new ExceptionBuilder();
        routeBuilder.from("direct:file").to("mock:http");
        return routeBuilder;
    }

当我将OneException添加到配置中时，为什么它说我必须在任何路由之前定义它

您需要移动此：

from("direct:file").to("mock:http");

调用

onException（）

后，转到

configure（）

方法。看起来是这样的：

public class ExceptionBuilder extends RouteBuilder{
   @Override
   public void configure() throws Exception {
       onException(Exception.class).process(new ExceptionProcessor());
       from("direct:file").to("mock:http");
   }
}

@Override
protected RouteBuilder createRouteBuilder() {
    return new ExceptionBuilder();
}

那么您的createRouteBuilder（）方法应该如下所示：

public class ExceptionBuilder extends RouteBuilder{
   @Override
   public void configure() throws Exception {
       onException(Exception.class).process(new ExceptionProcessor());
       from("direct:file").to("mock:http");
   }
}

@Override
protected RouteBuilder createRouteBuilder() {
    return new ExceptionBuilder();
}

我认为它给您一个错误的原因是因为路由应该包含

from（）

方法调用

---

如果您试图创建一个公共异常处理路由，则可以执行以下操作：

public class ExceptionBuilder extends RouteBuilder{
   @Override
   public void configure() throws Exception {
       from("direct:onException").process(new ExceptionProcessor());
   }
}

public class TestRouteBuilder extends RouteBuilder{
   @Override
   public void configure() throws Exception {
       onException(Exception.class).to("direct:onException");
       from("direct:start").to("mock:end");
   }
}

---

但是创建该类的想法是保持路由动态，而我的所有路由都需要有相同的OneException。。。它对我不起作用……我不确定你是否可以这样使用它，因为我认为Camel要求你在路由中使用

from（）

。我在文章末尾更新了一个选项，您可以使用它。使用OO继承并调用super.configure通常更容易。并将基类抽象化