messageLogFactory Vs MessageLogFactory in CPI Groovy scripting

[srini_reddy1]

I am trying to understand what is the difference between

MessageLogFactory and messageLogFactory

I am tried using below class to get the instance of message log but getting an exception as shown in error details.

com.sap.it.api.msglog.MessageLogFactory

Error Details java.lang.NoSuchMethodException: No signature of method: static com.sap.it.api.msglog.MessageLogFactory.getMessageLog() is applicable for argument types: (com.sap.gateway.ip.core.customdev.processor.MessageImpl) values: [com.sap.gateway.ip.core.customdev.processor.MessageImpl@172e1254]
Interface Java doc says this about the input parameter for MessageLogFactory interface.

The context object can be either a Camel Exchange, a CXF exchange, or a com.sap.it.api.msg.ExchangePropertyProvider.

This piece of code works fine

def logVariable(Message message, String name, String value) {
    boolean enableLogging = Boolean.parseBoolean(message.getProperty("enable_logging") as String)
    if (enableLogging) {
        def messageLog = messageLogFactory.getMessageLog(message)
        messageLog.setStringProperty(name, value)
    }
}

This code gives me an error

def logVariable1(Message message){
    def messageLog = MessageLogFactory.getMessageLog(message)
    messageLog.setStringProperty("Test_Log", "Test Log")
}

[MortenWittrock · Accepted solution]

Hi Srini

MessageLogFactory (upper case M) is the name of an interface in the com.sap.it.api.msglog package. messageLogFactory (lower case M), on the other hand, is the name of a variable made available to your scripts by the runtime. The variable references an instance of a class, which implements the MessageLogFactory (upper case M again) interface.

If you are curious about which class, run the following script:

import com.sap.gateway.ip.core.customdev.util.Message

def Message processData(Message message) {
    message.setBody(messageLogFactory.getClass().getName())
    return message
}

Right now it returns com.sap.it.op.agent.mpl.factory.impl.MessageLogFactoryImpl. The class is not important, though. What's important is that it implements the interface, and therefore lets you create MessageLog instances.

Regards,

Morten

[srini_reddy1 · Accepted solution]

Thanks, Morten.

It helps me understand it better now. I never thought of it as the implementation class for the interface. 🙂

Regards,

Srini

[MichaelBuonoGKN · Accepted solution]

Looks like more information about the two is here: https://help.sap.com/docs/cloud-integration/sap-cloud-integration/add-information-to-message-process...