Spring——自定义注解-蒲公英云

1.参数注解

注解

/**
- 字段参数注解
  *
- @author A.keung
- 2019/8/30 0030
- @Constraint 通过使用validatedBy指定与注解关联的验证器
  */
  @Target(ElementType.FIELD)
  @Retention(RetentionPolicy.RUNTIME)
  @Constraint(validatedBy = ParamsCheckConstraintValidator.class)
  public @interface ParamsCheck {
  //参数
  String[] paramValues();
  
  //提示
  String message() default “params error”;
  
  Class<?>[] groups() default {};
  
  Class<? extends Payload>[] payload() default {};
  }
验证器

/**
- 字段参数注解验证器
  *
- @author A.keung
- 2019/8/30 0030
  */
  public class ParamsCheckConstraintValidator implements ConstraintValidator {
  //注解参数
  private List paramValues;
  
  @Override
  public void initialize(ParamsCheck paramsCheck) {
```
 //初始化时获取注解上的值
 paramValues = Arrays.asList(paramsCheck.paramValues());
```
  }
  
  @Override
  public boolean isValid(Object o, ConstraintValidatorContext constraintValidatorContext) {
```
 return paramValues.contains(o);
```
  }
  }

测试

@RequestMapping(value = “testParamsCheck”,method = RequestMethod.POST)

public String testParamsCheck(@Validated @RequestBody User user) {
    log.info(JSON.toJSONString(user));
    return "OK";
}

@Data
@EqualsAndHashCode(callSuper = true)
@ToString(callSuper = true)
@TableName(“t_user”)
@NoArgsConstructor
//@AllArgsConstructor
public class User extends BaseEntity{

/**
 * 密码
 */
@TableField("password")
private String password;
/**
 * 手机
 */
@TableField("phone_number")
private String phoneNumber;
/**
 * 邮箱
 */
@TableField("email")
private String email;
/**
 * 昵称
 */
@TableField("nickname")
private String nickname;
/**
 * 权限
 */
@ParamsCheck(paramValues = {"ADMIN","USER"})
@TableField("role")
private String role;
/**
 * qqOpenId
 */
@TableField("qq_open_id")
private String qqOpenId;
/**
 * 头像地址
 */
@TableField("figure_url")
private String figureUrl;
/**
 * 是否启用
 */
@TableField("enable")
private Boolean enable;
private User(Builder builder) {
    setId(builder.id);
    setCreatedDatetime(builder.createdDatetime);
    setModifiedDatetime(builder.modifiedDatetime);
    setPassword(builder.password);
    setPhoneNumber(builder.phoneNumber);
    setEmail(builder.email);
    setNickname(builder.nickname);
    setRole(builder.role);
    setQqOpenId(builder.qqOpenId);
    setFigureUrl(builder.figureUrl);
    setEnable(builder.enable);
}

    public static final class Builder {
        private Long id;
        private Date createdDatetime;
        private Date modifiedDatetime;
        private String password;
        private String phoneNumber;
        private String email;
        private String nickname;
        private String role;
        private String qqOpenId;
        private String figureUrl;
        private Boolean enable;
        public Builder() {
        }
        public Builder id(Long val) {
            id = val;
            return this;
        }
        public Builder createdDatetime(Date val) {
            createdDatetime = val;
            return this;
        }
        public Builder modifiedDatetime(Date val) {
            modifiedDatetime = val;
            return this;
        }
        public Builder password(String val) {
            password = val;
            return this;
        }
        public Builder phoneNumber(String val) {
            phoneNumber = val;
            return this;
        }
        public Builder email(String val) {
            email = val;
            return this;
        }
        public Builder nickname(String val) {
            nickname = val;
            return this;
        }
        public Builder role(String val) {
            role = val;
            return this;
        }
        public Builder qqOpenId(String val) {
            qqOpenId = val;
            return this;
        }
        public Builder figureUrl(String val) {
            figureUrl = val;
            return this;
        }
        public Builder enable(Boolean val) {
            enable = val;
            return this;
        }
        public User build() {
            return new User(this);
        }
    }
}

" class="reference-link">

2.缓存注解

注解

/**
- 部门缓存注解
  *
- @author A.keung
- 2019/8/30 0030
  */
  @Target({ElementType.METHOD, ElementType.TYPE})
  @Retention(RetentionPolicy.RUNTIME)
  public @interface DeptCache {
  //#user.name或jack
  String keyExpr();
  }
切面

/**
- 部门缓存切面
  *
- @author A.keung
- 2019/8/30 0030
  */
  @Component
  @Aspect
  @Slf4j
  public class DeptCacheAspect {
  
  /**
  - 对含有注解的方法进行处理
    *
  - @param joinPoint
  - @return 返回值
    */
    @Around(“@annotation(com.ak.common.DeptCache)”)
    public Object process(ProceedingJoinPoint joinPoint) throws NoSuchMethodException {
    Object result = null;
    // 获取切入的方法对象
    // 代理对象的，没有包含注解
    Method m = ((MethodSignature) joinPoint.getSignature()).getMethod();
    // 目标对象反射获取的method对象才包含注解
    Method methodWithAnnotations = joinPoint.getTarget().getClass().getDeclaredMethod(joinPoint.getSignature().getName(), m.getParameterTypes());
    // 根据目标方法对象获取注解对象
    DeptCache deptCache = methodWithAnnotations.getDeclaredAnnotation(DeptCache.class);
    // 解析key
    String keyExpr = deptCache.keyExpr();
    Object[] argValues = joinPoint.getArgs();
    String key = parseKey(methodWithAnnotations, argValues, keyExpr);
    //根据key查询缓存
    String cache = findCache(key);
    if (StringUtils.isNotBlank(cache)) {
```
 return cache;
```
    }
    //执行目标方法
    try {
```
 result = joinPoint.proceed();
```
    } catch (Throwable throwable) {
```
 throwable.printStackTrace();
```
    }
    return result;
    }
    
    /**
  - 解析key（只支持String）
    *
  - @param method
  - @param argValues 方法参数值
  - @param keyExpr 注解值或表达式（含#）
  - @return key
  - @throws IllegalAccessException
    */
    private String parseKey(Method method, Object[] argValues, String keyExpr) {
    if (keyExpr.startsWith(“#”)) {
```
 String[] exprParamNames = keyExpr.substring(keyExpr.indexOf('#') + 1).split("\\.");
 // 获取方法参数名列表
 LocalVariableTableParameterNameDiscoverer discoverer = new LocalVariableTableParameterNameDiscoverer();
 String[] paramNames = discoverer.getParameterNames(method);
 Object argValue = null;
 for (int i = 0; i < paramNames.length; i++) {
     if (paramNames[i].equals(exprParamNames[0])) {
         argValue = argValues[i];
         break;
     }
 }
 try {
     for (int i = 1; i < exprParamNames.length; i++) {
         argValue = dealArg(argValue, exprParamNames[i]);
     }
     if (argValue instanceof String) {
         return (String) argValue;
     }
 } catch (IllegalAccessException e) {
     log.info("keyExpr:{}" + keyExpr);
     throw new RuntimeException("无法解析表达式:" + e.getMessage());
 }
 throw new RuntimeException("无法解析表达式");
```
    } else {
```
 return keyExpr;
```
    }
    }
    
    private Object dealArg(Object object, String fieldName) throws IllegalAccessException {
    if (object == null) {
```
 return null;
```
    }
    Class clazz = object.getClass();
    Field[] fields = clazz.getDeclaredFields();
    for (Field field : fields) {
```
 //属性可见
 field.setAccessible(true);
 if (fieldName.equals(field.getName())) {
     return field.get(object);
 }
```
    }
    return null;
    }

    private String findCache(String key) {
        double k = Math.random();
        log.info("k======"+k);
        if (k < 0.5) {
            return key + "_lt_0.5";
        }
        return null;
    }

测试

@RequestMapping(value = “testDeptCache”,method = RequestMethod.GET)

@DeptCache(keyExpr = "#user.nickname")
public String testDeptCache(User user) {
    return "OK";
}

" class="reference-link">

3.权限注解

注解

/**
- 权限注解
  *
- @author A.keung
- 2019/8/30 0030
  */
  @Target({ ElementType.METHOD, ElementType.TYPE})
  @Retention(RetentionPolicy.RUNTIME)
  public @interface PermissionCheck {
  String[] values() default {};
  }
拦截器

/**
- 权限注解拦截器
  *
- @author A.keung
- 2019/8/30 0030
  */
  public class PermissionCheckInterceptor extends HandlerInterceptorAdapter {
  @Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
```
 if (!handler.getClass().isAssignableFrom(HandlerMethod.class)) {
     return true;
 }
 PermissionCheck permission = findPermissionCheck((HandlerMethod) handler);
 //无权限注解
 if (permission == null) {
     return true;
 }
 //获取注解中的值
 String[] values = permission.values();
 //获取用户权限
 Map<String, String> userPermission = findUserPermission();
 for (String value : values) {
     if (userPermission.containsKey(value)) {
         return true;
     }
 }
 throw new Exception("No Permission");
```
  }
  
  /**
  - 模拟获取权限集
    *
  - @return 权限集
    */
    private Map findUserPermission() {
    Map permissionMap = new HashMap<>();
    permissionMap.put(“SELECT”, “”);
    permissionMap.put(“UPDATE”, “”);
    permissionMap.put(“DELETE”, “”);
    return permissionMap;
    }
    
    /**
  - 获取注解信息
    *
  - @param handlerMethod 方法对象
  - @return PermissionCheck注解
    */
    private PermissionCheck findPermissionCheck(HandlerMethod handlerMethod) {
    //方法上注解
    PermissionCheck permission = handlerMethod.getMethodAnnotation(PermissionCheck.class);
    if (permission == null) {
```
 //类上注解
 permission = handlerMethod.getBeanType().getAnnotation(PermissionCheck.class);
```
    }
    return permission;
    }
}
配置

/**
- Mvc配置类
- 在SpringBoot2.0之后的版本中WebMvcConfigurerAdapter过时了
- 采用以下方式：
- 1.继承WebMvcConfigurationSupport类
- 静态资源的访问的问题，在静态资源的访问的过程中，
- SpringBoot中的自动的配置会失效,不需要返回逻辑视图,可以选择继承此类
- 继承WebMvcConfigurationSupport，若多个类继承该类，只会有一个类中的重写的方法执行
- 2.实现WebMvcConfigurer接口
- @author A.keung
- 2019/8/30 0030
  */
  @Configuration
  public class WebMvcConfig implements WebMvcConfigurer {
  
  @Override
  public void addInterceptors(InterceptorRegistry interceptorRegistry) {
```
 interceptorRegistry.addInterceptor(new PermissionCheckInterceptor())
         .addPathPatterns("/**")
         .excludePathPatterns("/index/**","/api/login");
```
  }
  
  @Override
  public void configurePathMatch(PathMatchConfigurer pathMatchConfigurer) {
  
  }
  
  @Override
  public void configureContentNegotiation(ContentNegotiationConfigurer contentNegotiationConfigurer) {
  
  }
  
  @Override
  public void configureAsyncSupport(AsyncSupportConfigurer asyncSupportConfigurer) {
  
  }
  
  @Override
  public void configureDefaultServletHandling(DefaultServletHandlerConfigurer defaultServletHandlerConfigurer) {
  
  }
  
  @Override
  public void addFormatters(FormatterRegistry formatterRegistry) {
  
  }
  
  @Override
  public void addResourceHandlers(ResourceHandlerRegistry resourceHandlerRegistry) {
  
  }
  
  @Override
  public void addCorsMappings(CorsRegistry corsRegistry) {
  
  }
  
  @Override
  public void addViewControllers(ViewControllerRegistry viewControllerRegistry) {
  
  }
  
  @Override
  public void configureViewResolvers(ViewResolverRegistry viewResolverRegistry) {
  
  }
  
  @Override
  public void addArgumentResolvers(List list) {
  
  }
  
  @Override
  public void addReturnValueHandlers(List list) {
  
  }
  
  @Override
  public void configureMessageConverters(List> list) {
  
  }
  
  @Override
  public void extendMessageConverters(List> list) {
  
  }
  
  @Override
  public void configureHandlerExceptionResolvers(List list) {
  
  }
  
  @Override
  public void extendHandlerExceptionResolvers(List list) {
  
  }
  
  @Override
  public Validator getValidator() {
```
 return null;
```
  }
  
  @Override
  public MessageCodesResolver getMessageCodesResolver() {
```
 return null;
```
  }
  }

测试

@PermissionCheck(values = “SELECT”)

@RequestMapping(value = "testPermissionCheck",method = RequestMethod.GET)
public String testPermissionCheck() {
    return "OK";
}

Spring——自定义注解

1.参数注解

" class="reference-link">

2.缓存注解

" class="reference-link">

3.权限注解

发表评论取消回复

还没有评论，来说两句吧...

相关阅读

相关 Spring——自定义注解

相关 spring自定义注解

相关 spring自定义注解！

相关 spring 自定义注解

相关 Spring 自定义注解

相关 spring 自定义元注解

相关 spring 自定义注解

相关 spring自定义注解

相关 spring boot 自定义注解

相关 Spring Boot自定义注解

随便看看

MyBatis学习总结（4）——解决字段名与实体类属性名不相同的冲突

MyBatis学习总结（3）——优化MyBatis配置文件中的配置

Spring学习总结（2）——Spring的常用注解

Java基础学习总结（8）——super关键字

大型网站技术架构（六）网站的伸缩性架构

Java项目命名规范

教程文章

热评文章

1江湖小白之一起学Python （二）爬取数据的保存

2Java Shiro：简化身份验证和授权的安全框架

3Java中try()catch{}的使用方法

4Swagger注解-@ApiModel 和 @ApiModelProperty

5windows下强制杀死tomcat进程

6uni-app 条形码(一维码)/二维码生成实现

标签列表