3.用户注册-业务层开发

• 业务层要抛出可能存在的异常,而用户注册过程中可能出现的异常有用户名已被其他用户使用,服务器宕机,数据库宕机等问题,都是运行时异常,所以创建一个业务层异常基类,继承运行时异常,重写它的方法

  package com.cy.store.service.ex;
  
  
  public class ServiceException extends RuntimeException {
  
  
      public ServiceException() {
          super();
      }
  
      public ServiceException(String message) {
          super(message);
      }
  
      public ServiceException(String message, Throwable cause) {
          super(message, cause);
      }
  
      public ServiceException(Throwable cause) {
          super(cause);
      }
  
      protected ServiceException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
          super(message, cause, enableSuppression, writableStackTrace);
      }
  }
  

• 用户名已经存在的异常,继承业务层异常,并重写父类的方法

  package com.cy.store.service.ex;
  
  
  public class UsernameDuplicatedException extends ServiceException {
  
      public UsernameDuplicatedException() {
          super();
      }
  
      public UsernameDuplicatedException(String message) {
          super(message);
      }
  
      public UsernameDuplicatedException(String message, Throwable cause) {
          super(message, cause);
      }
  
      public UsernameDuplicatedException(Throwable cause) {
          super(cause);
      }
  
      protected UsernameDuplicatedException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
          super(message, cause, enableSuppression, writableStackTrace);
      }
  }
  

• 在插入过程中可能存在的其他异常,同样也继承业务层的异常基类,重写父类的方法

  package com.cy.store.service.ex;
  
  
  public class InsertException extends ServiceException{
  
      public InsertException() {
          super();
      }
  
      public InsertException(String message) {
          super(message);
      }
  
      public InsertException(String message, Throwable cause) {
          super(message, cause);
      }
  
      public InsertException(Throwable cause) {
          super(cause);
      }
  
      protected InsertException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
          super(message, cause, enableSuppression, writableStackTrace);
      }
  }
  

• 判断用户的用户名是否已被使用,如果是,抛出UsernameDuplicatedException异常
• 如果在注册过程中出现异常,抛出InsertException异常
• 用户注册前,对密码进行md5加密
  

package com.cy.store.service;

import com.cy.store.entity.User;


public interface IUserService {

    void registerUser(User user);

}

package com.cy.store.service.impl;

import com.cy.store.dao.UserDao;
import com.cy.store.entity.User;
import com.cy.store.service.IUserService;
import com.cy.store.service.ex.InsertException;
import com.cy.store.service.ex.UsernameDuplicatedException;
import com.cy.store.util.Encryption;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.Date;
import java.util.UUID;


@Service
public class UserServiceImpl implements IUserService{

    @Autowired
    private UserDao userDao;

    @Override
    public void registerUser(User user) {

        // 首先判断用户名是否已被占用,占用的话抛出异常
        User resuUser = userDao.selectUserByUsername(user.getUsername());
        if (resuUser != null) {
            throw new UsernameDuplicatedException("用户名已经被占用");
        }

        // 用户注册之前,补全除了用户输入的其他信息
        user.setIsDelete(0);
        user.setCreatedUser(user.getUsername());
        user.setModifiedUser(user.getUsername());
        Date date = new Date();
        user.setCreatedTime(date);
        user.setModifiedTime(date);

        // 用户密码加密(md5算法)
        String prePassword = user.getPassword();
        // 获取盐值(随机生成)
        String salt = UUID.randomUUID().toString().toUpperCase();
        // 密码加密处理
        String encryptedPassword = Encryption.getEncryptedPassword(prePassword, salt);
        user.setPassword(encryptedPassword);

        // 补全盐值,作用: 用户在登录的时候,通过前端输入的密码和后台取出来的盐值进行md5加密后,比对后台存储的加密过的密码,进行密码验证
        user.setSalt(salt);

        // 用户注册,注册失败,抛出注册过程中未知异常
        Integer row = userDao.insertUser(user);
        if (row != 1) {
            throw new InsertException("在插入数据的过程中发生了未知异常");
        }

    }
}

package com.cy.store.util;

import org.springframework.util.DigestUtils;


public class Encryption {

    public static String getEncryptedPassword(String password, String salt) {

        // md5三次加密
        for (int i = 0; i < 3; i++) {
            password = DigestUtils.md5DigestAsHex( (salt+password+salt).getBytes() ).toUpperCase();
        }

        return password;
    }
}