/**
   * 生成密钥并存入数据库OR从数据库取出密钥
   * */
  public SecretKey getDeskey() {

    try {

      SecretKey deskey = null;

      String orclURL = null;

      //读XML配置文件，取得ORACLE的URL
      SAXReader reader = new SAXReader();

      try {
        Document doc = reader.read(new File("E:\\SWECTool\\bea\\user_projects\\domains\\default\\config.xml"));
        Element connPoolEle = (Element) doc.selectSingleNode("/Domain/JDBCConnectionPool");
        orclURL = connPoolEle.attributeValue("URL");
        //System.out.println(orclURL);
      } catch (DocumentException e) {

        e.printStackTrace();
      }

      try {

        //Oracle的连接
        Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();

        String user = "smile";
        String password = "smile";

        Connection conn = DriverManager.getConnection(orclURL,user,password);

        if(conn != null){

         System.out.println("Connection Success "+conn);
        }else{

         System.out.println("Connection failed "+conn);
        }

        Statement stmt = conn.createStatement();

        try {

          //SQL文，从表DESKEY中检索出deskey的被拆分的各部分
          StringBuffer statement3 = new StringBuffer();

          statement3.append("SELECT B.*, A.COUNT ");
          statement3.append("FROM (SELECT COUNT AS COUNT FROM USER_TAB_COLUMNS ");
          statement3.append("WHERE TABLE_NAME='DESKEY') A, DESKEY B");

          //执行，从表DESKEY中检索出deskey的被拆分的各部分
          ResultSet resultKey = stmt.executeQuery(statement3.toString());

          if (resultKey.next()) {

            int fieldNumber2 = Integer.parseInt(resultKey.getString("COUNT"));

            String[] strdeskeyArray2 = new String[fieldNumber2];

            for (int i = 1; i <= fieldNumber2; i++) {
              strdeskeyArray2[i-1] = resultKey.getString;
            }

            //还原顺序
            if (fieldNumber2 > 2) {
              String strTemp1 = resultKey.getString(1);
              String strTemp2 = resultKey.getString(fieldNumber2 - 1);
              strdeskeyArray2[0] = strdeskeyArray2[fieldNumber2 - 1];
              strdeskeyArray2[fieldNumber2 - 2] = strTemp1;
              strdeskeyArray2[fieldNumber2 - 1] = strTemp2;
            }

            //测试用
            StringBuffer aa = new StringBuffer();
            for (int i = 0; i < fieldNumber2; i++) {
              if (i < fieldNumber2 - 1) {
                aa.append(strdeskeyArray2[i] + ":");
              } else {
                aa.append(strdeskeyArray2[i]);
              }
            }
            System.out.println("密钥数组顺序被整理成： " +aa.toString());

            StringBuffer str = new StringBuffer();
            for (int i = 1; i <= fieldNumber2; i++) {
              if (i < fieldNumber2) {
                str.append(strdeskeyArray2[i - 1] + ":");
              } else {
                str.append(strdeskeyArray2[i - 1]);
              }
            }

            //The bytes can be converted back to a SecretKey
            SecretKey deskey2 = new SecretKeySpec(hexToByte(str.toString()), "DES");
            //测试用
            System.out.println("这次取得的密钥是从数据库中取出来地！");
            return deskey2;
          }
        } catch (Exception e) {

          //e.printStackTrace();

          //生成密钥
          KeyGenerator keygen = KeyGenerator.getInstance("DES");
          deskey = keygen.generateKey();

          //测试用
          System.out.println("首次获得的密钥是： " + deskey.toString());

          //Get the bytes of the key
          byte[] deskeyBytes = deskey.getEncoded();

          String strdeskey = byte2hex(deskeyBytes);

          //测试用
          System.out.println("密钥被转换成字符串： " + strdeskey);

          String strdeskeyArray[] = strdeskey.split(":");

          int fieldNumber = strdeskeyArray.length;

          //打乱顺序后再存入数据库
          if (fieldNumber > 2) {
            String strTemp1 = strdeskeyArray[0];
            String strTemp2 = strdeskeyArray[fieldNumber - 2];
            strdeskeyArray[fieldNumber - 2] = strdeskeyArray[fieldNumber - 1];
            strdeskeyArray[fieldNumber - 1] = strTemp1;
            strdeskeyArray[0] = strTemp2;
          }

          //测试用
          StringBuffer bb = new StringBuffer();
          for (int i = 0; i < fieldNumber; i++) {
            if (i < fieldNumber - 1) {
              bb.append(strdeskeyArray[i] + ":");
            } else {
              bb.append(strdeskeyArray[i]);
            }
          }
          System.out.println("打乱顺序后的密钥数组为： " +bb.toString());

          //SQL文,建立存放密钥的表
          StringBuffer statement = new StringBuffer();

          statement.append("CREATE TABLE DESKEY ");
          statement.append("( ");
          for (int i = 0; i < fieldNumber; i++) {
            statement.append("KEY_" + i);

            if (i < fieldNumber -1) {
              statement.append(" CHAR(2), ");
            } else {
              statement.append(" CHAR(2) ");
            }

          }
          statement.append(")");

          //SQL文插入语句,把deskey拆开分别插入不同的字段中
          StringBuffer statement2 = new StringBuffer();

          statement2.append("INSERT INTO DESKEY ");

          statement2.append("( ");

          for (int i = 0; i < fieldNumber; i++) {

            if (i < fieldNumber -1) {
              statement2.append("KEY_" + i + ", ");
            } else {
              statement2.append("KEY_" + i);
            }

          }

          statement2.append(" ) ");

          statement2.append(" VALUES( ");

          for (int i = 0; i < fieldNumber; i++) {

            if (i < fieldNumber -1) {
              statement2.append("'" + strdeskeyArray[i] + "', ");
            } else {
              statement2.append("'" + strdeskeyArray[i] + "'");
            }

          }

          statement2.append(" )");

          //DESKEY表的建立
          stmt.executeUpdate(statement.toString());

          //提交
          conn.commit();

          //deskey的插入
          int result = stmt.executeUpdate(statement2.toString());

          //提交
          conn.commit();

          //测试用
          if (result > 0) {
            System.out.println("密钥已被成功插入到数据库，result = " + result);
          }

        }

      } catch (SQLException e) {
        e.printStackTrace();
      } catch (ClassNotFoundException e) {
        e.printStackTrace();
      } catch (InstantiationException e) {
        e.printStackTrace();
      } catch (IllegalAccessException e) {
        e.printStackTrace();
      }
      //测试用
      System.out.println("这次取得的密钥是首次生成的！");
      return deskey;
    } catch (Exception e) {

      e.printStackTrace();
      System.out.println("生成密钥失败");
      return null;
    }

  }