Dynamic Placeholder substitution in properties in java

Question

I wanted to substitute the placeholder dynamically in properties in a java application. Like

 WelcomeMessage=Welcome Mr. {firstName} {lastName} !!!
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Answer 1

You can use the MessageFormat class of Java SE. It allows you to do exactly what you ask for.

In your case the below code snippet must do the trick, assuming props contains all the properties loaded from your file.

MessageFormat.format((String) props.get("WelcomeMessage"), "First", "Last");

Note that your properties files should have index of parameters instead of named parameters as below.

WelcomeMessage=Welcome Mr. {0} {1} !!!