JAVA使用动态代理对象进行敏感字过滤代码实例

 package com.hopetesting.web.filter; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import java.io.BufferedReader; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; import java.lang.reflect.InvocationHandler; import java.lang.reflect.Method; import java.lang.reflect.Proxy; import java.util.ArrayList; import java.util.List; /** * @author newcityman * @date 2019/9/13 - 19:41 */ @WebFilter("/*") public class SensitiveWordsFilter implements Filter { public void destroy() { } public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException { //1、创建代理对象，增强getParameter方法 ServletRequest proxy_req = (ServletRequest) Proxy.newProxyInstance(req.getClass().getClassLoader(), req.getClass().getInterfaces(), new InvocationHandler() { @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { //判断是否是getParameter方法 //如果是，增强getParameter方法 if (method.getName().equals("getParameter")) { //增强返回值 //获取返回值 String value = (String) method.invoke(req, args); if (value != null) { for (String str : list) { if (value.contains(str)) { value = value.replace(str, "******"); } } } return value; } return method.invoke(req, args); } }); chain.doFilter(proxy_req, resp); } private List list = new ArrayList(); //敏感词汇集合 public void init(FilterConfig config) throws ServletException { try { //1、获取文件的真实路径 ServletContext servletContext = config.getServletContext(); String realPath = servletContext.getRealPath("/WEB-INF/classes/敏感词汇.txt"); //2、读取文件 BufferedReader br = new BufferedReader(new FileReader(realPath)); //3、将文件的每一行读取到list中 String line = null; while ((line = br.readLine()) != null) { list.add(line); } br.close(); System.out.println(list); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }