code: public void destroy(GSSCredential credential,
                          DestroyParams params)
          throws MyProxyException {
  
          if (credential == null) {
              throw new IllegalArgumentException("credential == null");
          }
  
          if (params == null) {
              throw new IllegalArgumentException("params == null");
          }
  
          String msg = params.makeRequest();
  
          Socket gsiSocket = null;
          OutputStream out = null;
          InputStream  in  = null;
  
          try {
              gsiSocket = getSocket(credential);
  
              out = gsiSocket.getOutputStream();
              in  = gsiSocket.getInputStream();
  
              if (!((GssSocket)gsiSocket).getContext().getConfState())
                  throw new Exception("Confidentiality requested but not available");
  
              // send message
              out.write(msg.getBytes());
              out.flush();
  
              if (logger.isDebugEnabled()) {
                  logger.debug("Req sent:" + params);
              }
  
              handleReply(in);
  
          } catch(Exception e) {
              throw new MyProxyException("MyProxy destroy failed.", e);
          } finally {
              // close socket
              close(out, in, gsiSocket);
          }
      }
docs: Removes delegated credentials from the MyProxy server.
  
  @param  credential
  The local GSI credentials to use for authentication.
  @param  params
  The parameters for the destroy operation.
  @exception MyProxyException
  If an error occurred during the operation.