攔截器抽象類繼承spring的HandlerInterceptorAdapter

package com.hsr.component.auth;
import com.hsr.core.annotations.AuthAdmin;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


public abstract class AuthAdminInterceptorDefault extends HandlerInterceptorAdapter {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        //認證使用者

        if(handler == null || !handler.getClass().isAssignableFrom(HandlerMethod.class)){
            return true;
        }

        HandlerMethod handlerMethod = (HandlerMethod) handler;
        Class beanType = handlerMethod.getBeanType();
        AuthAdmin classLevelAuthAnnotation = null;
        AuthAdmin methodLevelAuthAnnotation = null;
        if(beanType != null){
            classLevelAuthAnnotation = (AuthAdmin) beanType.getAnnotation(AuthAdmin.class);
        }
        methodLevelAuthAnnotation = handlerMethod.getMethodAnnotation(AuthAdmin.class);


        //先判斷方法級別的限制
        if(methodLevelAuthAnnotation != null){
            if(methodLevelAuthAnnotation.validate() == false){
                return true;
            }
            else{
                return _validateUser(request, response);
            }
        }

        //如果方法級別沒有註解在判斷類級別的
        if(classLevelAuthAnnotation != null){
            if(classLevelAuthAnnotation.validate() == false){
                return true;
            }
            else{
                return _validateUser(request, response);
            }
        }
        return true;
    }

    private boolean _validateUser(HttpServletRequest request,HttpServletResponse response)  throws IOException {
        //所有的請求都是要進行登陸認的
        Object obj = ensureCurrentUser(request,response);
        if(obj == null){

            //判斷請求是否是ajax請求
            String requestType = request.getHeader("X-Requested-With");
            if(requestType != null && !"".equals(requestType.trim())){
                if("XMLHttpRequest".toUpperCase().equals(requestType.toUpperCase())){
                    //getOutputStream與getWriter呼叫的問題
                    if(!response.isCommitted()) {
                        response.reset();
                    }
                    //告訴瀏覽器用UTF-8的編碼格式
                    response.setHeader("Content-type", "application/html;charset=UTF-8");
                    //是告訴servlet用UTF-8轉碼
                    response.setCharacterEncoding("UTF-8");
                    response.getWriter().write("LOGIN_TIME_OUT");
                }
            }
            else{
                response.sendRedirect(ensureRedirectLoginUrl(request,response));
            }
            return false;
        }else{
            return true;
        }
    }

    protected abstract Object ensureCurrentUser(HttpServletRequest request,HttpServletResponse response);
    protected abstract String ensureRedirectLoginUrl(HttpServletRequest request,HttpServletResponse response);
}
 

package com.edu.admin.base;

import com.hsr.component.auth.AuthAdminInterceptorDefault;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class AdminAuth extends AuthAdminInterceptorDefault {
    @Override
    protected Object ensureCurrentUser(HttpServletRequest request, HttpServletResponse response) {
        return AdminUtil.getCurrentUser();
    }

    @Override
    protected String ensureRedirectLoginUrl(HttpServletRequest request, HttpServletResponse response) {
        return "login";
    }
}
 

package com.hsr.core.annotations;

import java.lang.annotation.*;

/**
 認證管理端使用者
 */
@Documented
@Inherited
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface AuthAdmin {
    boolean validate() default true;
}

<mvc:interceptors>
   <bean class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor"/>
      <mvc:interceptor>
         <mvc:mapping path="/admin/**"/>
      <bean class="com.edu.admin.base.AdminAuth"/>
   </mvc:interceptor>
</mvc:interceptors>