SpringBoot用户CRUD

1.准备

http://start.spring.io/ 这里地址去直接生成你需要的项目信息，如何你本身ide以及集成了springboot 那么可以直接生成项目信息

　需要的知识：java，spring，springmvc，thymelafe

2开始

根据图片项目结构信息可以推断，我们需要写下面几个类：

 package com.dgw.boot.dgw.domain;

 /**
  * @author DGW-PC
  * @data   2018年7月17日
  */
 public class User{

     private Long id;
     private String name;
     private String email;

     public User() {

     }

     public User(Long id, String name, String email) {
         this.id = id;
         this.name = name;
         this.email = email;
     }

     @Override
     public String toString() {
         return "User [id=" + id + ", name=" + name + ", email=" + email + "]";
     }

     public Long getId() {
         return id;
     }

     public void setId(Long id) {
         this.id = id;
     }

     public String getName() {
         return name;
     }

     public void setName(String name) {
         this.name = name;
     }

     public String getEmail() {
         return email;
     }

     public void setEmail(String email) {
         this.email = email;
     }
 }    

Dao beans

public interface UserRepository {

    User savaOrUpdateUser(User user);

    void deleteUser(long id);

    User getUserById(long id);

    List<User> listUsre();

}

@Repository
public class UserRepositoryImpl implements UserRepository {

    private static AtomicLong count=new AtomicLong();
    private ConcurrentMap<Long, User> useMap=new ConcurrentHashMap<>();

    @Override
    public User savaOrUpdateUser(User user) {
        Long id = user.getId();
        if(id==null) {
            id=count.incrementAndGet();
            user.setId(id);
        }
        this.useMap.put(id, user);
        return user;
    }

    @Override
    public void deleteUser(long id) {
        this.useMap.remove(id);
    }

    @Override
    public User getUserById(long id) {
        return this.useMap.get(id);
    }

    @Override
    public List<User> listUsre() {
        return new ArrayList<>(this.useMap.values());
    }

}

控制器：

 /**
      * 从 用户存储库 获取用户列表
      * @return
      */
     private List<User> getUserlist() {
          return userRepository.listUser();
     }

     /**
      * 查询所用用户
      * @return
      */
     @GetMapping
     public ModelAndView list(Model model) {
         model.addAttribute("userList", getUserlist());
         model.addAttribute("title", "用户管理");
         return new ModelAndView("users/list", "userModel", model);
     }

     /**
      * 根据id查询用户
      * @param message
      * @return
      */
     @GetMapping("{id}")
     public ModelAndView view(@PathVariable("id") Long id, Model model) {
         User user = userRepository.getUserById(id);
         model.addAttribute("user", user);
         model.addAttribute("title", "查看用户");
         return new ModelAndView("users/view", "userModel", model);
     }

     /**
      * 获取 form 表单页面
      * @param user
      * @return
      */
     @GetMapping("/form")
     public ModelAndView createForm(Model model) {
         model.addAttribute("user", new User());
         model.addAttribute("title", "创建用户");
         return new ModelAndView("users/form", "userModel", model);
     }

     /**
      * 新建用户
      * @param user
      * @param result
      * @param redirect
      * @return
      */
     @PostMapping
     public ModelAndView create(User user) {
          user = userRepository.saveOrUpateUser(user);
         return new ModelAndView("redirect:/users");
     }

     /**
      * 删除用户
      * @param id
      * @return
      */
     @GetMapping(value = "delete/{id}")
     public ModelAndView delete(@PathVariable("id") Long id, Model model) {
         userRepository.deleteUser(id);

         model.addAttribute("userList", getUserlist());
         model.addAttribute("title", "删除用户");
         return new ModelAndView("users/list", "userModel", model);
     }

     /**
      * 修改用户
      * @param user
      * @return
      */
     @GetMapping(value = "modify/{id}")
     public ModelAndView modifyForm(@PathVariable("id") Long id, Model model) {
         User user = userRepository.getUserById(id);

         model.addAttribute("user", user);
         model.addAttribute("title", "修改用户");
         return new ModelAndView("users/form", "userModel", model);
     }