如何获得可增量索引 - 即在RouteBuilder的循环（）中使用？

Question

问：如何能够获得递增的指数 - 即，在RouteBuilder循环（）过程中使用 - 这样反复呼吁“直接：thingC”，将“过程”后续元素（在ArrayList中） ？

这里是配置（）方法...

private final org.apache.camel.Processor proc1 = new Processor1(); 
    private static final List<String> searchList = Arrays.asList("AA", "BB"); 
    private static final int z = searchList.size(); 
    private static int x = 0;  

    //***idea is to both elements using an index during the "loop".... Not working.... 

    @Override 
    public void configure() throws Exception { 

    from("timer://foo?fixedRate=true&period=" + 5000) //5 seconds...    
     .to("direct:thingB"); 

    from("direct:thingB") 
     .log("---------------------- (from(\"direct:thingB\"))... ----------x=" + x) 
     .loop(searchList.size()).to("direct:thingC"); 

    from("direct:thingC") 
     .log("---------------------- (from(\"direct:thingC\"))... ----------searchList.get(" + x++ + ")=" + searchList.get(x)); 
    } 

日志输出如下所示（指数不递增：总是选择相同的元件）... :-(

2017-09-01 16:13:19,142 | INFO | 43 - timer://foo | route15       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingB"))... ----------x=0 
2017-09-01 16:13:19,142 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(0)=BB 
2017-09-01 16:13:19,143 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(0)=BB 
2017-09-01 16:13:24,141 | INFO | 43 - timer://foo | route15       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingB"))... ----------x=0 
2017-09-01 16:13:24,141 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(0)=BB 
2017-09-01 16:13:24,142 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(0)=BB 

我们的目标是 - 有 - 这样的输出......

2017-09-01 16:13:19,142 | INFO | 43 - timer://foo | route15       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingB"))... ----------x=0 
2017-09-01 16:13:19,142 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(0)=AA 
2017-09-01 16:13:19,143 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(1)=BB 
2017-09-01 16:13:24,141 | INFO | 43 - timer://foo | route15       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingB"))... ----------x=0 
2017-09-01 16:13:24,141 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(0)=AA 
2017-09-01 16:13:24,142 | INFO | 43 - timer://foo | route16       | 232 - org.apache.camel.camel-core - 2.17.0.redhat-630187 | ---------------------- (from("direct:thingC"))... ----------searchList.get(1)=BB 

---

解决方案：按亚历山德罗的建议，下面

---

private final String s = "AA,BB"; 

@Override 
public void configure() throws Exception { 

    from("timer://foo?fixedRate=true&period=" + 5000) //5 seconds... 
      .setBody(constant(s))    
      .to("direct:thingB") 

    from("direct:thingB") 
      .split().tokenize(",") 
      .to("direct:thingC");  

    from("direct:thingC") 
      .log("body=" + body()); //note: this value looks like simple{AA} 
} 

Answer 1

不要使用loop。从文档：

该循环允许多次处理消息，可能以不同的方式进行每次迭代。主要在测试过程中有用
默认模式
通知默认情况下，循环使用整个循环中的相同交换。所以，既然你要处理的东西单一的元素，你可以“循环”上，将其设置为体，并使用split而不是从上一次迭代的结果将用于下一

。

from("timer://foo?fixedRate=true&period=" + 5000) //5 seconds...    
    setBody(searchList) 
    .to("direct:thingB"); 

from("direct:thingB") 
    .split() 
     .simple("${body}") 
     .log("This is element: ${body} [Element number ${exchangeProperties.CamelSplitIndex} of ${exchangeProperties.CamelSplitSize} total elements]") 
    .end() 

分配器将“破发”的List成单件和过程都在一个循环。

通常，如果输入或输出数据，请避免使用static字段。在这种情况下，最好将它们设置为主体，例如使用设置所需数据的Processor bean。