public String getIdentifier() {
        return identifier;
    }
Returns the identifier for the value in patch corresponding to this
outcome, or null if the value in the patch was null.

@return
    The identifier for the value in patch corresponding to this
    outcome, or null if the value was null.
guacamole/src/main/java/org/apache/guacamole/rest/jsonpatch/APIPatchOutcome.java