@Override
    public Matching clone() {
        try {
            return (Matching)super.clone();
        }
        catch (CloneNotSupportedException e) {
            throw new RuntimeException("Programming error");
        }
    }
Sets the terminator string which terminates an exact matched
sequence in queries (used if type is EXACT).
config-model/src/main/java/com/yahoo/schema/document/Matching.java