properties - How can I specify a default value for a system property in a Java web app? -


It seems that it should be so easy, but I'm beating my head for the day.

I have a simple Java web app that embeds the JT into an executable jar, and I am using system properties to define the configuration information that is different from the app Keeping me I like that I can set the system properties on the command line with -D for example 

  java -Dbackend = backend_url -jar ...   
 Is there a way to set the  default  value to the property of such a system?   
 
 
 If you are reading those properties  
 you read about it Can:

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