将 2 个 JSON 数据合并为一个生成异常答案

【问题标题】：Merging 2 JSON data into one generating exception将 2 个 JSON 数据合并为一个生成异常
【发布时间】：2015-08-07 21:12:44
【问题描述】：

我遇到了一个小问题..我有以下 Mule 流程：-

<flow name="PostgresSQLFlow1" doc:name="PostgresSQLFlow1">
        <http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8082" doc:name="HTTP" path="db"/>
        <scatter-gather doc:name="Scatter-Gather">
            <processor-chain>
                <flow-ref name="PostgresSQLSub-Flow" doc:name="Flow Reference"/>
                <logger message="PostgresSql Done !!!" level="INFO" doc:name="Logger"/>
            </processor-chain>
            <processor-chain>
                <flow-ref name="MSSQLSub-Flow" doc:name="Flow Reference"/>
                <logger message="MSSQL Done !!!" level="INFO" doc:name="Logger"/>
            </processor-chain>
        </scatter-gather>

        <set-payload value="....... Process Complete !!!! #[message.payload]" doc:name="Set Payload"/>
    </flow>

    <sub-flow name="PostgresSQLSub-Flow" doc:name="PostgresSQLSub-Flow">
        <jdbc-ee:outbound-endpoint exchange-pattern="request-response" connector-ref="Database_Global2" queryKey="RetriveQuery" queryTimeout="-1" doc:name="Database (JDBC)"/>
        <json:object-to-json-transformer doc:name="Object to JSON"/>
        <logger message="Postgres Data :- #[message.payload]" level="INFO" doc:name="Logger"/>
    </sub-flow>
    <sub-flow name="MSSQLSub-Flow" doc:name="MSSQLSub-Flow">
     <jdbc-ee:outbound-endpoint exchange-pattern="request-response" connector-ref="Database_Global" queryKey="RetriveQuery" queryTimeout="-1" doc:name="Database (JDBC)"/>
        <json:object-to-json-transformer doc:name="Object to JSON"/>
        <logger message="MSSQL Data :- #[message.payload]" level="INFO" doc:name="Logger"/>
   </sub-flow>

现在我从两个子流中获取 JSON 数据，如下所示：-

MSSQL Data :- [{"AGE":5,"DESIGNATION":"Software Engineer","NAME":"Sidray","ID":288},{"AGE":55,"DESIGNATION":"Software Engineer"}]
Postgres Data :- [{"AGE":33,"DESIGNATION":"Software Engineer","NAME":"Anil","ID":2}]

现在我想将它合并到一个 JSON 消息中...... 我尝试了以下方法：- 在每个子流中我使用<json:json-to-object-transformer returnClass="java.util.HashMap" /> 然后I used <set-payload value="#[groovy:payload.inject([:]) {result, part -> result.putAll(part); result}]" /> 我已将以下内容作为参考：- I merge two different payloads into one payload 但没用..我得到以下异常：-

org.mule.routing.CompositeRoutingException: Exception was found for route(s): 0, 1. Message payload is of type: String
 at org.mule.routing.CollectAllAggregationStrategy.aggregateWithFailedRoutes(CollectAllAggregationStrategy.java:51)
 at org.mule.routing.CollectAllAggregationStrategy.aggregate(CollectAllAggregationStrategy.java:38)
 at org.mule.routing.ScatterGatherRouter.processResponses(ScatterGatherRouter.java:197)
  + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)

请帮助我如何将这 2 个 json 数据合并到一个 json 中？？

更新流程：-

<flow name="PostgresSQLFlow1" doc:name="PostgresSQLFlow1">
<http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8082" doc:name="HTTP" path="db"/>
     <scatter-gather doc:name="Scatter-Gather">
         <processor-chain>
            <flow-ref name="PostgresSQLSub-Flow" doc:name="Flow Reference"/>
            <logger message="PostgresSql Done !!!" level="INFO" doc:name="Logger"/>
            </processor-chain>
         <processor-chain>
          <flow-ref name="MSSQLSub-Flow" doc:name="Flow Reference"/>
            <logger message="MSSQL Done !!!" level="INFO" doc:name="Logger"/>
        </processor-chain>
     </scatter-gather>
  <set-payload value="#[groovy:payload.inject([:]) {result, part -> result.putAll(part); result}]" />

   </flow>

<sub-flow name="PostgresSQLSub-Flow" doc:name="PostgresSQLSub-Flow">
 <jdbc-ee:outbound-endpoint exchange-pattern="request-response" connector-ref="Database_Global2" queryKey="RetriveQuery" queryTimeout="-1" doc:name="Database (JDBC)"/>
 <json:json-to-object-transformer returnClass="java.util.HashMap" />
   <logger message="Postgres Data :- #[message.payload]" level="INFO" doc:name="Logger"/>
 </sub-flow>

 <sub-flow name="MSSQLSub-Flow" doc:name="MSSQLSub-Flow">
 <jdbc-ee:outbound-endpoint exchange-pattern="request-response" connector-ref="Database_Global" queryKey="RetriveQuery" queryTimeout="-1" doc:name="Database (JDBC)"/>
 <json:json-to-object-transformer returnClass="java.util.HashMap" />
 <logger message="MSSQL Data :- #[message.payload]" level="INFO" doc:name="Logger"/>

 </sub-flow>

我得到的异常：-

INFO  2014-09-17 22:00:08,380 [[MultipleDBWithMSSQLAndPostgresSQL].ScatterGatherWorkManager.01] org.mule.lifecycle.AbstractLifecycleManager: Initialising: 'Database_Global2.dispatcher.1519448919'. Object is: EEJdbcMessageDispatcher
INFO  2014-09-17 22:00:08,380 [[MultipleDBWithMSSQLAndPostgresSQL].ScatterGatherWorkManager.02] org.mule.lifecycle.AbstractLifecycleManager: Initialising: 'Database_Global.dispatcher.1649935156'. Object is: EEJdbcMessageDispatcher
INFO  2014-09-17 22:00:08,381 [[MultipleDBWithMSSQLAndPostgresSQL].ScatterGatherWorkManager.02] org.mule.lifecycle.AbstractLifecycleManager: Starting: 'Database_Global.dispatcher.1649935156'. Object is: EEJdbcMessageDispatcher
INFO  2014-09-17 22:00:08,381 [[MultipleDBWithMSSQLAndPostgresSQL].ScatterGatherWorkManager.01] org.mule.lifecycle.AbstractLifecycleManager: Starting: 'Database_Global2.dispatcher.1519448919'. Object is: EEJdbcMessageDispatcher
ERROR 2014-09-17 22:00:08,586 [[MultipleDBWithMSSQLAndPostgresSQL].connector.http.mule.default.receiver.02] org.mule.exception.DefaultMessagingExceptionStrategy: 
********************************************************************************
Message               : Exception was found for route(s): 0, 1. Message payload is of type: String
Code                  : MULE_ERROR--2
--------------------------------------------------------------------------------
Exception stack is:
1. Exception was found for route(s): 0, 1. Message payload is of type: String (org.mule.routing.CompositeRoutingException)
  org.mule.routing.CollectAllAggregationStrategy:51 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/routing/CompositeRoutingException.html)
--------------------------------------------------------------------------------
Root Exception stack trace:
org.mule.routing.CompositeRoutingException: Exception was found for route(s): 0, 1. Message payload is of type: String
    at org.mule.routing.CollectAllAggregationStrategy.aggregateWithFailedRoutes(CollectAllAggregationStrategy.java:51)
    at org.mule.routing.CollectAllAggregationStrategy.aggregate(CollectAllAggregationStrategy.java:38)
    at org.mule.routing.ScatterGatherRouter.processResponses(ScatterGatherRouter.java:197)
    + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)
********************************************************************************

【问题讨论】：

你把合并逻辑放在哪里了？它似乎破坏了scatter-gather。
我在每个子流程中在 object-to-json-transformer 之后使用了 json-to-object-transformer，然后我使用了 set-payload value="#[groovy:payload.inject([:] ) {result, part -> result.putAll(part); result}]" 在 PostgresSQLFlow1 中分散和聚集后
实际上，为什么要从对象到 JSON 再返回到对象？为什么不直接使用 JDBC 端点返回的映射列表？
请检查我更新的流程
JDBC 端点生成地图列表，而不是 JSON 字符串，因此 json-to-object-transformer 不可能工作。只需删除它们，让scatter-gather 为您提供来自 JDBC 端点的数据。

标签： java json mule

【解决方案1】：

JDBC 端点生成映射列表，而不是 JSON 字符串，因此 json-to-object-transformer 可能无法工作。只需删除它们，然后让 scatter-gather 为您提供来自 JDBC 端点的数据。

【讨论】：

【解决方案2】：

所以，按照大卫的建议，最终的工作代码是：-

 <flow name="PostgresSQLFlow1" doc:name="PostgresSQLFlow1">
            <http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8082" doc:name="HTTP" path="db"/>
            <scatter-gather doc:name="Scatter-Gather">
             <processor-chain>
               <flow-ref name="PostgresSQLSub-Flow" doc:name="Flow Reference"/>
                <logger message="PostgresSql Done !!!" level="INFO" doc:name="Logger"/>
               </processor-chain>
               <processor-chain>
                 <flow-ref name="MSSQLSub-Flow" doc:name="Flow Reference"/>
                 <logger message="MSSQL Done !!!" level="INFO" doc:name="Logger"/>
               </processor-chain>
            </scatter-gather>
           <set-payload value="....... Process Complete !!!! #[message.payload]" doc:name="Set Payload"/>
        </flow>

        <sub-flow name="PostgresSQLSub-Flow" doc:name="PostgresSQLSub-Flow">
            <jdbc-ee:outbound-endpoint exchange-pattern="request-response" connector-ref="Database_Global2" queryKey="RetriveQuery" queryTimeout="-1" doc:name="Database (JDBC)"/>
            <logger message="Postgres Data :- #[message.payload]" level="INFO" doc:name="Logger"/>
        </sub-flow>
        <sub-flow name="MSSQLSub-Flow" doc:name="MSSQLSub-Flow">
         <jdbc-ee:outbound-endpoint exchange-pattern="request-response" connector-ref="Database_Global" queryKey="RetriveQuery" queryTimeout="-1" doc:name="Database (JDBC)"/>
          <logger message="MSSQL Data :- #[message.payload]" level="INFO" doc:name="Logger"/>
       </sub-flow>

【讨论】：