Java Camel框架：丢失处理器中的消息体
所有，
这是一条简单的路线：
... JsonValidator是一个简单的Java bean，我扩展了处理器。 在这里，我想确保在使用Jackson将JSON解组到我的POJO之前继续使用unmarshal调用之前传递所有必需字段。
我现在所做的只是一行：
public void process(Exchange exchange) throws Exception { String input = exchange.getIn().getBody(String.class); }
简单地调用exchange.getIn（）。getBody（String.class）会导致我的路径中的下一个（解组）步骤抛出错误，说没有任何解组。 事实上，我通过在JsonValidator之后添加另一个处理器来测试这个 – 在那里，交换体不是null但是它是空的。
这是错误：
com.fasterxml.jackson.databind.JsonMappingException: No content to map due to end-of-input at [Source: org.apache.camel.converter.stream.InputStreamCache@78f0a00a; line: 1, column: 1] at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:164) at com.fasterxml.jackson.databind.ObjectMapper._initForReading(ObjectMapper.java:2931) at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:2873) at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2080) at org.apache.camel.component.jackson.JacksonDataFormat.unmarshal(JacksonDataFormat.java:105) at org.apache.camel.processor.UnmarshalProcessor.process(UnmarshalProcessor.java:65) at org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:72) at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:398) at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191) at org.apache.camel.processor.Pipeline.process(Pipeline.java:118) at org.apache.camel.processor.Pipeline.process(Pipeline.java:80) at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191) at org.apache.camel.component.jetty.CamelContinuationServlet.service(CamelContinuationServlet.java:151) at javax.servlet.http.HttpServlet.service(HttpServlet.java:668) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:684) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1496) at org.eclipse.jetty.servlets.MultiPartFilter.doFilter(MultiPartFilter.java:136) at org.apache.camel.component.jetty.CamelFilterWrapper.doFilter(CamelFilterWrapper.java:44) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1467) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:499) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1086) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:428) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1020) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116) at org.eclipse.jetty.server.Server.handle(Server.java:370) at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:494) at org.eclipse.jetty.server.AbstractHttpConnection.content(AbstractHttpConnection.java:982) at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.content(AbstractHttpConnection.java:1043) at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:865) at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:240) at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82) at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:667) at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:52) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543) at java.lang.Thread.run(Thread.java:744)
我错过了什么？
流（通常）只能读一次。 阅读后，您必须将结果存储在交换中：
public void process(Exchange exchange) throws Exception { String input = exchange.getIn().getBody(String.class); exchange.getIn().setBody(input); }
或者，您可以让Camel按照Camel文档中的描述进行缓存。