一、HandlerInterceptor 用法

第一步：注册拦截器

第二步：继承HandlerInterceptor ，实现拦截器

package com.iflashbuy.limanman;import java.util.Iterator;import java.util.Map;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.web.servlet.HandlerInterceptor;import org.springframework.web.servlet.ModelAndView;public class ControlInterceptor implements HandlerInterceptor{	private Logger logger  = LoggerFactory.getLogger(getClass());	/**	 * 执行完控制器后调用，即离开时	 */	@Override	public void afterCompletion(HttpServletRequest request,			HttpServletResponse response, Object arg2, Exception arg3)					throws Exception {	}	@Override	public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3)			throws Exception {		// TODO Auto-generated method stub			}	@Override	public boolean preHandle(HttpServletRequest request, HttpServletResponse arg1, Object arg2) throws Exception {		int i = 1;		try {			@SuppressWarnings("unchecked")			Map
    
      parmMap = request.getParameterMap();			Iterator
     
       iter = parmMap.keySet().iterator();			while (iter.hasNext()) {				Object key = iter.next();				Object value = parmMap.get(key);				logger.info("第" + i + "个param---->{}-{}", key, value);				i = i + 1;			}		} catch (Exception e) {			i = 1;		}		i = 1;		return true;	}	}
     
    

二、后台打印信息效果

三、拓展使用拦截器实现http基本认证

/**	 * 执行完控制器后调用，即离开时	 */	@Override	public void afterCompletion(HttpServletRequest request,			HttpServletResponse response, Object arg2, Exception arg3)			throws Exception {		logger.info("className--->" + arg2);		logger.info("request--->" + request);	}	@Override	public void postHandle(HttpServletRequest request,			HttpServletResponse response, Object arg2, ModelAndView arg3)			throws Exception {	}	@Override	public boolean preHandle(HttpServletRequest request,			HttpServletResponse response, Object arg2) throws Exception {		String sessionAuth = (String) request.getSession().getAttribute("auth");		if (sessionAuth != null) {			System.out.println("this is next step");			nextStep(request, response);		} else {			if (!checkHeaderAuth(request, response)) {				response.setStatus(401);				response.setHeader("Cache-Control", "no-store");				response.setDateHeader("Expires", 0);				response.setHeader("WWW-authenticate", "Basic Realm=\"请输入管理员账号密码\"");				return false;			}		}		return true;	}	private boolean checkHeaderAuth(HttpServletRequest request,			HttpServletResponse response) throws IOException {		String auth = request.getHeader("Authorization");		System.out.println("auth encoded in base64 is " + getFromBASE64(auth));		if ((auth != null) && (auth.length() > 6)) {			auth = auth.substring(6, auth.length());			String decodedAuth = getFromBASE64(auth);			System.out.println("auth decoded from base64 is " + decodedAuth);			request.getSession().setAttribute("auth", decodedAuth);			return true;		} else {			return false;		}	}	private String getFromBASE64(String s) {		if (s == null)			return null;		try {			byte[] encodeBase64 = Base64.encodeBase64(s.getBytes("UTF-8"));			return new String(encodeBase64);		} catch (UnsupportedEncodingException e) {			return null;		}	}	public void nextStep(HttpServletRequest request,			HttpServletResponse response) throws IOException {		System.out.println("you can go to the controller");	}