@Override
    public String toString() {
        return this.getClass().getName() + " - " + runnable.toString();
    }
unwrap to original/unwrapped {@link Runnable}.

@see TtlUnwrap#unwrap(Object)
@since 2.11.4
ttl2-compatible/src/main/java/com/alibaba/ttl/TtlRunnable.java