@Validate(rules = { 
        @Rule(value = "required:true", message = "用户名不能为空"), 
        @Rule(value = "checkUsernameExists:", message = "用户名不能重复"), 
        @Rule(value = "maxlength:10", message = "输入长度最多是 10 的字符串（汉字算一个字符）。"), 
        @Rule(value = "minlength:5", message = "输入长度最小是 5 的字符串（汉字算一个字符）。")
})
private String username;

@Validate(rules = { @Rule(value = "required:true", message = "密码不能为空") })
private String password;

public static void main(String[] args) {
    User user = new User();
    user.setUsername("admin");
    IValidateService validate = new BaseValidateService();
    validate.validate(user);
}

    @Override
    public Boolean validate(Object attrValue, Class<?> attrType, Object params) {
        if (attrValue.equals("admin")) { return true; }
        return false;
    }
}

validate:
	packagesToScan: com.dasuanzhuang.halo.test	
    message:
      required: 不能为空
      maxlength: 长度不能超过{0}
      minlength: 长度不能小于{0}	

@Validate(rules = { 
        @Rule(value = "required:true", message = "用户名不能为空"), 
        @Rule(value = "checkUsernameExists:", message = "用户名不能重复")
})
private String username;

系统默认的校验器包括required，maxlength，minlength，也可以自定义校验器，以下校验器标识为checkUsernameExists

@ValidationRegister("checkUsernameExists")
public class UsernameValidation implements Validation {

    @Override
    public Boolean validate(Object attrValue, Class<?> attrType, Object params) {
        if (attrValue.equals("admin")) { return true; }
        return false;
    }
}

继承Validation 并且 需要配置注解ValidationRegister，实现validate(Object attrValue, Class<?> attrType, Object params) 方法，attrValue 传入属性值，attrType属性类型，params 冒号后面的参数，如果是多个值，以String[] 形式传递

required，maxlength，minlength 使用说明：
required:true  对象不为空，如果是String类，默认会验证是否为空字符串
maxlength:10   表示长度不能超过10
minlength:10   表示长度最小不能小于10

@Validate(
        rules = {
                @Rule(value = "required:true", message = "角色不能为空")
        },
        objClass  = Role.class
)
private Role role ;

@Validate(
        rules = {
                @Rule(value = "required:true", message = "角色list不能为空")
        },
        objClass  = Role.class
)
private List<Role> roles ; 

@Validate(
        rules = {
                @Rule(value = "required:true", message = "角色map不能为空")
        },
        objClass  = Role.class
)
private Map<String,Role> roleMap;

 @Validate(rules = { 
        @Rule(value = "required:true", message = "用户名不能为空"), 
        @Rule(value = "checkUsernameExists:", message = "用户名不能重复"), 
        @Rule(value = "maxlength:10", message = "输入长度最多是 10 的字符串（汉字算一个字符）。"), 
        @Rule(value = "minlength:5", message = "输入长度最小是 5 的字符串（汉字算一个字符）。")
}, objClass  = Role.class)