if an attribute is not present in map, How to replace the values in template string using strsubsitutor as null or empty string

Question

I have a string

String templateString = "The ${animal} jumps over the ${target}.";
valuesMap.put("animal", "quick brown fox");
StrSubstitutor sub = new StrSubstitutor(valuesMap);
String resolvedString = sub.replace(templateString);

But there is no entry for attr target in valuesMap. Final resolvedString would be The quick brown fox jumps over the ${target}.

Instead of ${target}, it need to be empty. Values in templatestring which doesn't have key in map should be empty or null.

required The quick brown fox jumps over the.

How to handle this

Answer 1

Your Map<String,String> valuesMap contains just the couple key, value "animal", "quick brown fox", you have to add the couple "target", "" to your map like below:

String templateString = "The ${animal} jumps over the ${target}.";
valuesMap.put("animal", "quick brown fox");
valuesMap.put("target", ""); //<-- adding the new couple to the map
StrSubstitutor sub = new StrSubstitutor(valuesMap);
String resolvedString = sub.replace(templateString);