/**
   * Looks up providers, and returns the property (and its associated provider) mapping the key, if
   * any. The order in which the providers are looked up is the provider-preference order, as
   * specificed in the security properties file.
   */
  private static ProviderProperty getProviderProperty(String key) {
    ProviderProperty entry = null;

    List providers = Providers.getProviderList().providers();
    for (int i = 0; i < providers.size(); i++) {

      String matchKey = null;
      Provider prov = (Provider) providers.get(i);
      String prop = prov.getProperty(key);

      if (prop == null) {
        // Is there a match if we do a case-insensitive property name
        // comparison? Let's try ...
        for (Enumeration e = prov.keys(); e.hasMoreElements() && prop == null; ) {
          matchKey = (String) e.nextElement();
          if (key.equalsIgnoreCase(matchKey)) {
            prop = prov.getProperty(matchKey);
            break;
          }
        }
      }

      if (prop != null) {
        ProviderProperty newEntry = new ProviderProperty();
        newEntry.className = prop;
        newEntry.provider = prov;
        return newEntry;
      }
    }

    return entry;
  }
 /**
  * Returns the provider installed with the specified name, if any. Returns null if no provider
  * with the specified name is installed or if name is null.
  *
  * @param name the name of the provider to get.
  * @return the provider of the specified name.
  * @see #removeProvider
  * @see #addProvider
  */
 public static Provider getProvider(String name) {
   return Providers.getProviderList().getProvider(name);
 }