xml - 使用编码(marshal)将对象带到 Camel 中的 xml

Question

我目前有工作代码，但我认为它没有以有效的方式使用 Camel。我想知道是否有人可以帮助我使用 Camel 中的 Marshaling 功能。现在我基本上是调用自定义 Java 代码来完成它。过去两天我一直在尝试在没有这种自定义 Java 代码的情况下获得它，但我一直遇到老实说我并不真正理解的问题。我认为，如果有人看到一些有用的东西并告诉我如何通过用几条路线替换它来摆脱大部分代码，那会更容易。

这是我的路线

<bean id="mockSql" class="tutorial.simple.route.MockSql"/>
<bean id="sqlToXml" class="tutorial.simple.route.sqlToXml"/>
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
<route>
    <from uri="timer://foo?repeatCount=1"/>
    <to uri="bean:mockSql?method=populate"/>
    <to uri="bean:sqlToXml?method=process"/>
</route>

这是我的第一个 java 类/bean

 package tutorial.simple.route;
 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;

 import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;

 import org.apache.camel.CamelContext;
 import org.apache.camel.Exchange;
 import org.apache.camel.Handler;
 import org.apache.camel.Message;
 import org.apache.camel.impl.DefaultCamelContext;
 import org.apache.log4j.Level;
 import org.apache.log4j.Logger;

 @XmlRootElement
 public class MockSql implements Serializable {

    private String name="name";
    private String job="job";

 private static final Logger log = Logger.getLogger("mockSql");
 ArrayList <HashMap> ary = new ArrayList<HashMap>();
    public MockSql() throws Exception{
        // CamelContext context = new DefaultCamelContext();


        log.setLevel(Level.DEBUG);
        log.debug("constructed mock sql \n \n");

    }
    @Handler
     public void populate(Exchange ex) throws Exception{    


         MockSql m = new MockSql();
         m.name="my name";
         m.job="my job";
         ex.getIn().setBody(m);
         log.debug("populated mock sql");
     }
     @XmlElement 
     public String getName(){
        return name;
    }

    @XmlElement
    public String getJob(){
        return job;
    }
 }

我的第二个 bean

package tutorial.simple.route;


import java.io.File;

import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;


public class sqlToXml implements Processor { 
private static final Logger log = Logger.getLogger("mockSql");
@Override
public void process(Exchange arg0) throws Exception {

    System.out.println("MyProcessor started");

    /*String myString = arg0.getIn().getBody(String.class);
    log.setLevel(Level.DEBUG);
    log.debug(myString);*/

    MockSql m = arg0.getIn().getBody(MockSql.class);

    log.setLevel(Level.DEBUG);
    log.debug(m.getName());
    try {

           // create JAXB context and initializing Marshaller
           JAXBContext jaxbContext = JAXBContext.newInstance(MockSql.class);
           Marshaller jaxbMarshaller = jaxbContext.createMarshaller();

           // for getting nice formatted output
           jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);

           //specify the location and name of xml file to be created
           File XMLfile = new File("C:\\Users\\myname\\Desktop\\myxml.xml");

           String x;

           // Writing to XML file
           jaxbMarshaller.marshal(m, XMLfile); 
           // Writing to console
           jaxbMarshaller.marshal(m, System.out); 

          } catch (JAXBException e) {
           // some exception occured
           e.printStackTrace();
          }

         }

}

所以，我试图让这个更像“ Camel ”的尝试如下:

<bean id="mockSql" class="tutorial.simple.route.MockSql"/>
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
    <dataFormats>
        <jaxb prettyPrint="true" contextPath="org.apache.camel.example" id="myJaxb"/>
    </dataFormats>
    <route>
        <from uri="timer://foo?repeatCount=1"/>
        <to uri="bean:mockSql?method=populate"/>
        <marshal ref="myJaxb"/>
        <to uri="file:/src/data/myxml.xml"/>
    </route>
</camelContext>

</beans>

我收到以下错误:

[ERROR] 无法执行目标 org.apache.camel:camel-maven-plugin:2.12.0.redhat-610379:run (default-cli) on project simple-route: null: MojoExecutionException: InvocationTargetException : org.apache.camel.util.ObjectHelper.notNull(Ljava/lang/Object;Ljava/lang/String;)V -> [帮助 1

堆栈跟踪:

[INFO] <<< camel-maven-plugin:2.12.0.redhat-610379:run (default-cli) @ simple-route <<<
[INFO] 
[INFO] --- camel-maven-plugin:2.12.0.redhat-610379:run (default-cli) @ simple-route ---
[INFO] Using org.apache.camel.spring.Main to initiate a CamelContext
[INFO] Starting Camel ...
[pache.camel.spring.Main.main()] MainSupport                    INFO  Apache Camel 2.12.0.redhat-610379 starting
[pache.camel.spring.Main.main()] SpringCamelContext             INFO  Apache Camel 2.12.0.redhat-610379 (CamelContext: camel) is starting
[pache.camel.spring.Main.main()] ManagedManagementStrategy      INFO  JMX is enabled
[pache.camel.spring.Main.main()] DefaultTypeConverter           INFO  Loaded 176 type converters
[pache.camel.spring.Main.main()] SpringCamelContext             INFO  AllowUseOriginalMessage is enabled. If access to the original message is not needed, then its recommended to turn this option off as it may improve performance.
[pache.camel.spring.Main.main()] SpringCamelContext             INFO  StreamCaching is not in use. If using streams then its recommended to enable stream caching. See more details at http://camel.apache.org/stream-caching.html
[ERROR] *************************************
[ERROR] Error occurred while running main from: org.apache.camel.spring.Main
[ERROR] 
java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.camel.maven.RunMojo$1.run(RunMojo.java:487)
    at java.lang.Thread.run(Thread.java:744)
Caused by: java.lang.NoSuchMethodError: org.apache.camel.util.ObjectHelper.notNull(Ljava/lang/Object;Ljava/lang/String;)V
    at org.apache.camel.converter.jaxb.JaxbDataFormat.doStart(JaxbDataFormat.java:247)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:59)
    at org.apache.camel.processor.MarshalProcessor.doStart(MarshalProcessor.java:118)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:59)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:103)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:89)
    at org.apache.camel.processor.DelegateAsyncProcessor.doStart(DelegateAsyncProcessor.java:79)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:59)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:103)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:89)
    at org.apache.camel.processor.RedeliveryErrorHandler.doStart(RedeliveryErrorHandler.java:1154)
    at org.apache.camel.support.ChildServiceSupport.start(ChildServiceSupport.java:41)
    at org.apache.camel.support.ChildServiceSupport.start(ChildServiceSupport.java:28)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:59)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:103)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:89)
    at org.apache.camel.processor.interceptor.DefaultChannel.doStart(DefaultChannel.java:153)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:59)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:103)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:61)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:103)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:89)
    at org.apache.camel.processor.MulticastProcessor.doStart(MulticastProcessor.java:994)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:59)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:103)
    at org.apache.camel.util.ServiceHelper.startServices(ServiceHelper.java:89)
    at org.apache.camel.processor.DelegateAsyncProcessor.doStart(DelegateAsyncProcessor.java:79)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.util.ServiceHelper.startService(ServiceHelper.java:74)
    at org.apache.camel.impl.RouteService.startChildService(RouteService.java:329)
    at org.apache.camel.impl.RouteService.warmUp(RouteService.java:158)
    at org.apache.camel.impl.DefaultCamelContext.doWarmUpRoutes(DefaultCamelContext.java:2150)
    at org.apache.camel.impl.DefaultCamelContext.safelyStartRouteServices(DefaultCamelContext.java:2080)
    at org.apache.camel.impl.DefaultCamelContext.doStartOrResumeRoutes(DefaultCamelContext.java:1868)
    at org.apache.camel.impl.DefaultCamelContext.doStartCamel(DefaultCamelContext.java:1740)
    at org.apache.camel.impl.DefaultCamelContext.doStart(DefaultCamelContext.java:1579)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.impl.DefaultCamelContext.start(DefaultCamelContext.java:1547)
    at org.apache.camel.spring.SpringCamelContext.maybeStart(SpringCamelContext.java:221)
    at org.apache.camel.spring.SpringCamelContext.onApplicationEvent(SpringCamelContext.java:118)
    at org.apache.camel.spring.CamelContextFactoryBean.onApplicationEvent(CamelContextFactoryBean.java:303)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:96)
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:334)
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:948)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.context.support.FileSystemXmlApplicationContext.<init>(FileSystemXmlApplicationContext.java:140)
    at org.springframework.context.support.FileSystemXmlApplicationContext.<init>(FileSystemXmlApplicationContext.java:94)
    at org.apache.camel.spring.Main.createDefaultApplicationContext(Main.java:176)
    at org.apache.camel.spring.Main.doStart(Main.java:140)
    at org.apache.camel.support.ServiceSupport.start(ServiceSupport.java:61)
    at org.apache.camel.main.MainSupport.run(MainSupport.java:148)
    at org.apache.camel.main.MainSupport.run(MainSupport.java:352)
    at org.apache.camel.spring.Main.main(Main.java:73)
    ... 6 more

Answer 1

java.lang.NoSuchMethodError 表示库不匹配。如果所有 Camel 库都使用相同的版本，请检查您的 Maven/Gradle/Ivy 依赖项。