code: private boolean setupEphemeralECDHKeys() {
          int index = -1;
          if (supportedCurves != null) {
              // if the client sent the supported curves extension, pick the
              // first one that we support;
              for (int curveId : supportedCurves.curveIds()) {
                  if (SupportedEllipticCurvesExtension.isSupported(curveId)) {
                      index = curveId;
                      break;
                  }
              }
              if (index < 0) {
                  // no match found, cannot use this ciphersuite
                  return false;
              }
          } else {
              // pick our preference
              index = SupportedEllipticCurvesExtension.DEFAULT.curveIds()[0];
          }
          String oid = SupportedEllipticCurvesExtension.getCurveOid(index);
          ecdh = new ECDHCrypt(oid, sslContext.getSecureRandom());
          return true;
      }
docs: the client requested, return false. Otherwise (all is well), return true.