Make String.format(“%s”, arg) display null-valued arguments differently from “null”

Question

Consider the custom toString() implementation of a bean:

@Override
public String toString() {
    String.format(\"this is %s\", this.someField);
}
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Answer 1

The nicest solution, in my opinion, is using Guava's Objects method, firstNonNull. The following method will ensure you will print an empty string if someField is ever null.

String.format("this is %s", MoreObjects.firstNonNull(this.someField, ""));

Guava docs.