code: protected Object activateProxy()
      {
          if ( settings == null )
          {
              return null;
          }
          final Proxy proxy = settings.getActiveProxy();
          if ( proxy == null )
          {
              return null;
          }
  
          final List<String> properties = new ArrayList<String>();
          final String protocol = proxy.getProtocol();
          final String prefix = isEmpty( protocol ) ? "" : ( protocol + "." );
  
          final String host = proxy.getHost();
          final String hostProperty = prefix + "proxyHost";
          final String hostValue = isEmpty( host ) ? null : host;
          setProperty( properties, hostProperty, hostValue );
          final int port = proxy.getPort();
          final String portProperty = prefix + "proxyPort";
          final String portValue = ( port == 0 || port == -1 ) ? null : String.valueOf( port );
          setProperty( properties, portProperty, portValue );
          final String username = proxy.getUsername();
          final String userProperty = prefix + "proxyUser";
          final String userValue = isEmpty( username ) ? null : username;
          setProperty( properties, userProperty, userValue );
          final String password = proxy.getPassword();
          final String passwordProperty = prefix + "proxyPassword";
          final String passwordValue = isEmpty( password ) ? null : password;
          setProperty( properties, passwordProperty, passwordValue );
          final String nonProxyHosts = proxy.getNonProxyHosts();
          final String nonProxyHostsProperty = prefix + "nonProxyHosts";
          final String nonProxyHostsValue = isEmpty( nonProxyHosts ) ? null : nonProxyHosts.replace( ',', '|' );
          setProperty( properties, nonProxyHostsProperty, nonProxyHostsValue );
          getLog().debug( "Proxy settings: " + hostProperty + "=" + hostValue + ", " + portProperty + "=" + portValue
              + ", " + userProperty + "=" + userValue + ", " + passwordProperty + "="
              + ( passwordValue == null ? "null" : "<PasswordNotLogged>" ) + ", " + nonProxyHostsProperty + "="
              + nonProxyHostsValue );
          return properties;
      }
docs: Called to install the plugins proxy settings.