code: public void enable() {
          if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
              Tr.debug(this, tc, "enable chain " + this);
          }
          enabled = true;
      }
docs: Enable this chain: this happens automatically for the http chain,
  but is delayed on the ssl chain until ssl support becomes available.
  This does not change the chain's state. The caller should
  make subsequent calls to perform actions on the chain.