字符编码过滤器

本是古典何须时尚 2022-05-25 22:54 189阅读 0赞

项目结构如下：

![20180420160544517][]

index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
    %>
    
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head>
        <base href="<%=basePath%>">
        
        <title>添加图书信息</title>
    	<meta http-equiv="pragma" content="no-cache">
    	<meta http-equiv="cache-control" content="no-cache">
    	<meta http-equiv="expires" content="0">    
    	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    	<meta http-equiv="description" content="This is my page">
    	
      </head>
      
      <body>
        <center>
        	<form action="addServlet" method="post">
        		<table>
        			<tr>
        				<td>图书名称:</td>
        				<td><input type="text" name="name"></td>
        			</tr>
        			<tr>
        				<td><input type="submit" value="提交"></td>
        			</tr>
        		</table>
        	</form>
        </center>
      </body>
    </html>

addServlet.java

package com.lv;
    
    import java.io.IOException;
    import java.io.PrintWriter;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    /**
     * Servlet implementation class addServlet
     */
    @WebServlet("/addServlet")
    public class addServlet extends HttpServlet {
    	private static final long serialVersionUID = 1L;
           
        /**
         * @see HttpServlet#HttpServlet()
         */
        public addServlet() {
            super();
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		doPost(request, response);
    	}
    
    	/**
    	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		PrintWriter out =response.getWriter();
    		String name=request.getParameter("name");
    		out.print(name);
    	}
    
    }

myFilter.java

package com.filter;
    
    import java.io.IOException;
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.FilterConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    import javax.servlet.annotation.WebFilter;
    
    /**
     * Servlet Filter implementation class myFilter
     */
    public class myFilter implements Filter {
    	String encoding="utf-8";
        /**
         * Default constructor. 
         */
        public myFilter() {
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see Filter#destroy()
    	 */
    	public void destroy() {
    		// TODO Auto-generated method stub
    	}
    
    	/**
    	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
    	 */
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
    		request.setCharacterEncoding(encoding);
    		response.setContentType("text/html;charset="+encoding);
    		chain.doFilter(request, response);
    	}
    
    	/**
    	 * @see Filter#init(FilterConfig)
    	 */
    	public void init(FilterConfig fConfig) throws ServletException {
    		// TODO Auto-generated method stub
    	}
    
    }

运行效果以下：

index.jsp

![20180420160931413][]

addServlet

![20180420161028889][]

[20180420160544517]: /images/20220526/6f8da53116184d3cbdd768b7894f5e12.png
[20180420160931413]: /images/20220526/f459e174c2364e80849e8285cfbe8f7c.png
[20180420161028889]: /images/20220526/40f7d336cdf34d389dca54999aa4c777.png