关于@Valid注解大全以及用法规范

//用户发送POST请求创建新的用户
@PostMapping
public User create(@RequestBody User user){
    /**
        一些数据持久化操作，如：写入数据库
    **/
    //打印用户提交的信息
    System.out.println(user.getId());
    System.out.println(user.getUsername());
    System.out.println(user.getPassword());
    System.out.println(user.getBirthday());
    return user;
}

//用户发送POST请求创建新的用户
@PostMapping
public User create(@RequestBody User user){
    if( StringUtils.isBlank(user.getPassword())){
        //用户输入密码为空，进行异常处理
    }
    /**
        一些数据持久化操作，如：写入数据库
    **/
    //打印用户提交的信息
    System.out.println(user.getId());
    System.out.println(user.getUsername());
    System.out.println(user.getPassword());
    System.out.println(user.getBirthday());
    return user;
}

import org.hibernate.validator.constraints.NotBlank;
public class User {
    public interface UserSimpleView{}
    public interface UserDetailView extends UserSimpleView{}
    private String username;
    //给该属性加入NotBlank非空的约束
    @NotBlank
    private String password;
    private String id;
    private Date birthday;
    public Date getBirthday() {
        return birthday;
    }
    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }
    @JsonView(UserSimpleView.class)
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    @JsonView(UserSimpleView.class)
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    @JsonView(UserDetailView.class)
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
}

@PostMapping
public User create(@Valid @RequestBody User user,
                       BindingResult errors){
    if (errors.hasErrors()){
        //异常处理
        errors.getAllErrors().stream().forEach(error -> System.out.println(error.getDefaultMessage()));
    }
    user.setId("1");
    System.out.println(user.getId());
    System.out.println(user.getUsername());
    System.out.println(user.getPassword());
    System.out.println(user.getBirthday());
    return user;
}