@CanIgnoreReturnValue
    public ChainingPrincipalNameTransformer addTransformers(final List<PrincipalNameTransformer> input) {
        transformers.addAll(input);
        return this;
    }
Add transformers chaining principal name transformer.

@param input the input
@return the chaining principal name transformer
core/cas-server-core-util-api/src/main/java/org/apereo/cas/util/transforms/ChainingPrincipalNameTransformer.java