在dispatcher-servlet.xml中添加拦截器：
<mvc:interceptors>
<!-- 定义在这里的，所有的都会拦截-->
<mvc:interceptor>
<mvc:mapping path="/manage/**"/>
<!--不需要拦截的接口-->
<!--<mvc:exclude-mapping path="/manage/user/login.do"/>-->
<bean class="com.mmall.controller.common.interceptor.AuthorityInterceptor" />
</mvc:interceptor>
</mvc:interceptors>
拦截的目录的规则
/ 从根目录
/* 拦截当前目录一级的
/** 拦截当前目录和它的子目录
新建拦截器实现HandlerInterceptor接口：
public class AuthorityInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
return false;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
}
}
拦截器的执行顺序preHandle->controller-> postHandle-> afterCompletion, preHandle返回false将不在执行后面的方法。
preHandle中实现拦截逻辑：
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
HandlerMethod handlerMethod = (HandlerMethod)handler;
String methodName = handlerMethod.getMethod().getName();
String className = handlerMethod.getBean().getClass().getSimpleName();
//解析参数,具体的参数key以及value是什么，我们打印日志
StringBuffer requestParamBuffer = new StringBuffer();
Map paramMap = request.getParameterMap();
Iterator it = paramMap.entrySet().iterator();
while (it.hasNext()){
Map.Entry entry = (Map.Entry) it.next();
String mapKey = (String) entry.getKey();
String mapValue = StringUtils.EMPTY;
//request这个参数的map，里面的value返回的是一个String[]
Object object = entry.getValue();
if (object instanceof String[]){
String[] strs = (String[]) object;
mapValue = Arrays.toString(strs);
}
requestParamBuffer.append(mapKey).append("=").append(mapValue);
}
log.info("权限拦截器拦截到请求,className:{},methodName:{},param:{}",className,methodName,requestParamBuffer.toString());
User user = null;
String loginToken = CookieUtil.readLoginToken(request);
if(org.apache.commons.lang.StringUtils.isNotEmpty(loginToken)){
String userJsonStr = RedisShardedPoolUtil.get(loginToken);
user = JsonUtil.string2Obj(userJsonStr,User.class);
}
//以下就是项目中的逻辑代码，可根据项目的需求灵活改变
if(user==null || user.getRole()== Const.Role.ROLE_CUSTOMER){
response.reset();
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json;charset=UTF-8");
PrintWriter out = response.getWriter();
//上传由于富文本的控件要求，要特殊处理返回值，这里面区分是否登录以及是否有权限
if(user == null){
if(org.apache.commons.lang.StringUtils.equals(className,"ProductManageController") && org.apache.commons.lang.StringUtils.equals(methodName,"richtextImgUpload")){
Map resultMap = Maps.newHashMap();
resultMap.put("success",false);
resultMap.put("msg","请登录管理员");
out.print(JsonUtil.obj2String(resultMap));
}else{
out.print(JsonUtil.obj2String(ServerResponse.createByErrorMessage("拦截器拦截,用户未登录")));
}
}else{
if(org.apache.commons.lang.StringUtils.equals(className,"ProductManageController") && org.apache.commons.lang.StringUtils.equals(methodName,"richtextImgUpload")){
Map resultMap = Maps.newHashMap();
resultMap.put("success",false);
resultMap.put("msg","无权限操作");
out.print(JsonUtil.obj2String(resultMap));
}else{
out.print(JsonUtil.obj2String(ServerResponse.createByErrorMessage("拦截器拦截,用户无权限操作")));
}
}
out.flush();
out.close();//geelynote 这里要关闭
return false;
}
return true;
}
- 在拦截器中排除一些特殊的接口有两种方法：
1.在dispatcher-servlet.xml中添加<mvc:exclude-mapping path=""/>:
<mvc:interceptors>
<!-- 定义在这里的，所有的都会拦截-->
<mvc:interceptor>
<mvc:mapping path="/manage/**"/>
<!--不需要拦截的接口-->
<mvc:exclude-mapping path="/manage/user/login.do"/>
<bean class="com.mmall.controller.common.interceptor.AuthorityInterceptor" />
</mvc:interceptor>
</mvc:interceptors>
2.通过preHandle中的handler对象获取类名、方法来进行逻辑判断：
String methodName = handlerMethod.getMethod().getName();
String className = handlerMethod.getBean().getClass().getSimpleName();
- 通过
HttpServletRequest获取请求参数，进行逻辑处理：
StringBuffer requestParamBuffer = new StringBuffer();
Map paramMap = request.getParameterMap();
Iterator it = paramMap.entrySet().iterator();
while (it.hasNext()){
Map.Entry entry = (Map.Entry)it.next();
String mapKey = (String)entry.getKey();
String mapValue = StringUtils.EMPTY;
//request这个参数的map，里面的value返回的是一个String[]
Object obj = entry.getValue();
if(obj instanceof String[]){
String[] strs = (String[])obj;
mapValue = Arrays.toString(strs);
}
requestParamBuffer.append(mapKey).append("=").append(mapValue);
}
需要注意的是HttpServletRequest获取到的参数是map需要处理后使用。
- 如果进行了拦截将不在调用contoller中的方法，而preHandle返回的是布尔类型，所以需要对返回进行处理：
if(user == null || (user.getRole().intValue() != Const.Role.ROLE_ADMIN)){
//返回false.即不会调用controller里的方法
response.reset();//geelynote 这里要添加reset，否则报异常 getWriter() has already been called for this response.
response.setCharacterEncoding("UTF-8");//geelynote 这里要设置编码，否则会乱码
response.setContentType("application/json;charset=UTF-8");//geelynote 这里要设置返回值的类型，因为全部是json接口。
PrintWriter out = response.getWriter();
Map resultMap = Maps.newHashMap();
resultMap.put("status",1);
if(user == null){
resultMap.put("msg","请登录管理员");
}else{
resultMap.put("msg","无权限操作");
}
out.print(JsonUtil.obj2String(resultMap));
out.flush();
out.close();//geelynote 这里要关闭
return false;
}
接口请求效果
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