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<String> list = new ArrayList<String>(); //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();    }  }}