SpringMVC ServletRequestAttributes的应用

小灰灰 2023-06-29 12:00 5阅读 0赞

在SpringMVC的源代码中提供了一个封装过的ThreadLocal，其中保存了每次请求的HttpServletRequest对象，（详细请看org.springframework.web.context.request.ServletRequestAttributes的源代码） 。

这样我们就可以进行简单封装一下写一个工具进行使用：

import lombok.extern.slf4j.Slf4j;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.web.context.request.RequestAttributes;
    import org.springframework.web.context.request.RequestContextHolder;
    import org.springframework.web.context.request.ServletRequestAttributes;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    
    
    @Slf4j
    public class RequestHolder { 
    
        /** * 获取request * * @return HttpServletRequest */
        public static HttpServletRequest getRequest() { 
            log.debug("getRequest -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            ServletRequestAttributes servletRequestAttributes = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes());
            if (null == servletRequestAttributes) { 
                return null;
            }
            return servletRequestAttributes.getRequest();
        }
    
        /** * 获取Response * * @return HttpServletRequest */
        public static HttpServletResponse getResponse() { 
            log.debug("getResponse -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            ServletRequestAttributes servletRequestAttributes = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes());
            if (null == servletRequestAttributes) { 
                return null;
            }
            return servletRequestAttributes.getResponse();
        }
    
        /** * 获取session * * @return HttpSession */
        public static HttpSession getSession() { 
            log.debug("getSession -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            HttpServletRequest request = null;
            if (null == (request = getRequest())) { 
                return null;
            }
            return request.getSession();
        }
    
        /** * 获取session的Attribute * * @param name session的key * @return Object */
        public static Object getSession(String name) { 
            log.debug("getSession -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            ServletRequestAttributes servletRequestAttributes = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes());
            if (null == servletRequestAttributes) { 
                return null;
            }
            return servletRequestAttributes.getAttribute(name, RequestAttributes.SCOPE_SESSION);
        }
    
        /** * 添加session * * @param name * @param value */
        public static void setSession(String name, Object value) { 
            log.debug("setSession -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            ServletRequestAttributes servletRequestAttributes = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes());
            if (null == servletRequestAttributes) { 
                return;
            }
            servletRequestAttributes.setAttribute(name, value, RequestAttributes.SCOPE_SESSION);
        }
    
        /** * 清除指定session * * @param name * @return void */
        public static void removeSession(String name) { 
            log.debug("removeSession -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            ServletRequestAttributes servletRequestAttributes = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes());
            if (null == servletRequestAttributes) { 
                return;
            }
            servletRequestAttributes.removeAttribute(name, RequestAttributes.SCOPE_SESSION);
        }
    
        /** * 获取所有session key * * @return String[] */
        public static String[] getSessionKeys() { 
            log.debug("getSessionKeys -- Thread id :{}, name : {}", Thread.currentThread().getId(), Thread.currentThread().getName());
            ServletRequestAttributes servletRequestAttributes = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes());
            if (null == servletRequestAttributes) { 
                return null;
            }
            return servletRequestAttributes.getAttributeNames(RequestAttributes.SCOPE_SESSION);
        }
    }