读取mule 3中的json有效负载数据

<set-payload value="#[payloadAs(String)]" doc:name="Set Payload"/>

<dw:transform-message doc:name="Transform Message">
    <dw:set-payload><![CDATA[%dw 1.0
        %output application/java
        ---
        read(payload, "application/json")
    ]]></dw:set-payload>
</dw:transform-message>

<dw:transform-message doc:name="Transform Message">
    <dw:set-payload><![CDATA[%dw 1.0
        %output application/json
        ---
        {
            "field1": payload.field1,
            "field2": payload.field2
        }
    ]]></dw:set-payload>
</dw:transform-message>