在开发 Web 项目的时候,经常需要过滤器来处理一些请求,包括字符集转换什么的,记录请求日志什么的等等。在之前的 Web 开发中,我们习惯把过滤器配置到 web.xml 中,但是在 SpringBoot 中,兵没有这个配置文件,该如何操作呢?
1.编写一个过滤器:
import lombok.extern.slf4j.Slf4j; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.util.Iterator; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; @Slf4j @WebFilter(urlPatterns="/dyflight/*") public class IpFilter implements Filter{ /** * 默认限制时间(单位:ms)3600000,3600(s), */ private static final long LIMITED_TIME_MILLIS = 10 * 1000; /** * 用户连续访问最高阀值,超过该值则认定为恶意操作的IP,进行限制 */ private static final int LIMIT_NUMBER = 5; /** * 用户访问最小安全时间,在该时间内如果访问次数大于阀值,则记录为恶意IP,否则视为正常访问 */ private static final int MIN_SAFE_TIME = 5000; private FilterConfig config; @Override public void init(FilterConfig filterConfig) throws ServletException { this.cOnfig= filterConfig; //设置属性filterConfig } /* (non-Javadoc) * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain) */ @SuppressWarnings("unchecked") @Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest) servletRequest; HttpServletResponse respOnse= (HttpServletResponse) servletResponse; ServletContext cOntext= config.getServletContext(); // 获取限制IP存储器:存储被限制的IP信息 //MaplimitedIpMap = (Map ) context.getAttribute("limitedIpMap"); ConcurrentHashMap limitedIpMap = (ConcurrentHashMap ) context.getAttribute("limitedIpMap"); // 过滤受限的IP filterLimitedIpMap(limitedIpMap); // 获取用户IP String ip = IPUtil.getRemoteIpAddr(request); System.err.println("ip:"+ip); // 判断是否是被限制的IP,如果是则跳到异常页面 if (isLimitedIP(limitedIpMap, ip)) { long limitedTime = limitedIpMap.get(ip) - System.currentTimeMillis(); // 剩余限制时间(用为从毫秒到秒转化的一定会存在些许误差,但基本可以忽略不计) request.setAttribute("remainingTime", ((limitedTime / 1000) + (limitedTime % 1000 > 0 &#63; 1 : 0))); System.err.println("ip访问过于频繁:"+ip); throw new RuntimeException("ip访问过于频繁"); } // 获取IP存储器 ConcurrentHashMap ipMap = (ConcurrentHashMap ) context.getAttribute("ipMap"); // 判断存储器中是否存在当前IP,如果没有则为初次访问,初始化该ip // 如果存在当前ip,则验证当前ip的访问次数 // 如果大于限制阀值,判断达到阀值的时间,如果不大于[用户访问最小安全时间]则视为恶意访问,跳转到异常页面 if (ipMap.containsKey(ip)) { Long[] ipInfo = ipMap.get(ip); ipInfo[0] = ipInfo[0] + 1; log.debug("当前第[" + (ipInfo[0]) + "]次访问"); if (ipInfo[0] > LIMIT_NUMBER) { Long ipAccessTime = ipInfo[1]; Long currentTimeMillis = System.currentTimeMillis(); log.debug("ip访问过于频繁:currentTimeMillis: "+currentTimeMillis+" - ipAccessTime:"+ipAccessTime+" : " + (currentTimeMillis - ipAccessTime) + "<="+ MIN_SAFE_TIME); if (currentTimeMillis - ipAccessTime <= MIN_SAFE_TIME) { limitedIpMap.put(ip, currentTimeMillis + LIMITED_TIME_MILLIS); request.setAttribute("remainingTime", LIMITED_TIME_MILLIS); log.debug("ip访问过于频繁:LIMITED_TIME_MILLIS:"+LIMITED_TIME_MILLIS); log.debug("ip访问过于频繁:"+ip); throw new RuntimeException("ip访问过于频繁"); } else { initIpVisitsNumber(ipMap, ip); } } } else { initIpVisitsNumber(ipMap, ip); System.out.println("您首次访问该网站"); } context.setAttribute("ipMap", ipMap); chain.doFilter(request, response); } @Override public void destroy() { // TODO Auto-generated method stub } /** * @Description 过滤受限的IP,剔除已经到期的限制IP * @param limitedIpMap */ private void filterLimitedIpMap(ConcurrentHashMap limitedIpMap) { if (limitedIpMap == null) { return; } Set keys = limitedIpMap.keySet(); Iterator keyIt = keys.iterator(); long currentTimeMillis = System.currentTimeMillis(); while (keyIt.hasNext()) { long expireTimeMillis = limitedIpMap.get(keyIt.next()); log.debug("expireTimeMillis <= currentTimeMillis:"+ expireTimeMillis+" <="+ currentTimeMillis); if (expireTimeMillis <= currentTimeMillis) { keyIt.remove(); } } } /** * @Description 是否是被限制的IP * @param limitedIpMap * @param ip * @return true : 被限制 | false : 正常 */ private boolean isLimitedIP(ConcurrentHashMap limitedIpMap, String ip) { if (limitedIpMap == null || ip == null) { // 没有被限制 return false; } Set keys = limitedIpMap.keySet(); Iterator keyIt = keys.iterator(); while (keyIt.hasNext()) { String key = keyIt.next(); if (key.equals(ip)) { // 被限制的IP return true; } } return false; } /** * 初始化用户访问次数和访问时间 * * @param ipMap * @param ip */ private void initIpVisitsNumber(ConcurrentHashMap ipMap, String ip) { Long[] ipInfo = new Long[2]; ipInfo[0] = 0L;// 访问次数 ipInfo[1] = System.currentTimeMillis();// 初次访问时间 ipMap.put(ip, ipInfo); } }
2. 创建一个监听器:需要初始化俩个容器:
import lombok.extern.slf4j.Slf4j; import javax.servlet.ServletContext; import javax.servlet.ServletContextEvent; import javax.servlet.ServletContextListener; import javax.servlet.annotation.WebListener; import java.util.concurrent.ConcurrentHashMap; @Slf4j @WebListener public class MyApplicationListener implements ServletContextListener { @Override public void contextInitialized(ServletContextEvent sce) { log.debug("liting: contextInitialized"); log.debug("MyApplicationListener初始化成功"); ServletContext cOntext= sce.getServletContext(); // IP存储器 ConcurrentHashMapipMap = new ConcurrentHashMap<>(); context.setAttribute("ipMap", ipMap); // 限制IP存储器:存储被限制的IP信息 ConcurrentHashMap limitedIpMap = new ConcurrentHashMap (); context.setAttribute("limitedIpMap", limitedIpMap); log.debug("ipmap:"+ipMap.toString()+";limitedIpMap:"+limitedIpMap.toString()+"初始化成功。。。。。"); } @Override public void contextDestroyed(ServletContextEvent sce) { // TODO Auto-generated method stub } }
3.iputil
import javax.servlet.http.HttpServletRequest; import java.net.InetAddress; import java.net.UnknownHostException; public class IPUtil { public static String getRemoteIpAddr(HttpServletRequest request) { String ip = request.getHeader("x-forwarded-for"); if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("Proxy-Client-IP"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("WL-Proxy-Client-IP"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("HTTP_CLIENT_IP"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getHeader("HTTP_X_FORWARDED_FOR"); } if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { ip = request.getRemoteAddr(); if("127.0.0.1".equals(ip)||"0:0:0:0:0:0:0:1".equals(ip)){ //根据网卡取本机配置的IP InetAddress inet=null; try { inet = InetAddress.getLocalHost(); } catch (UnknownHostException e) { e.printStackTrace(); } ip= inet.getHostAddress(); } } return ip; } }
4配置
springboot启动类中添加过滤器和监听器的包扫描
@ServletComponentScan(basePackages="cn.xxx.common")
spring web.xml
过滤器
ipFilter com.xxxx.common.filter.IpFilter ipFilter /dyflight/**
监听器:
com.xxxx.common.Listener.MyApplicationListener
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。