简单粗暴 每个servlet之前都插入一段代码解决 乱码问题
response.setHeader("content-type", "text/html;charset=UTF-8");
response.setCharacterEncoding("UTF-8");
request.setCharacterEncoding("UTF-8");
response.setHeader("content-type", "text/html;charset=UTF-8");
response.setCharacterEncoding("UTF-8");
request.setCharacterEncoding("UTF-8");