過濾器接口與實現字符編碼過濾器實…

[1]過濾器的原理

[2]過濾鏈

[3]Filter接口

*public void init(FilterConfig filterConfig)throws ServletException//過濾器初始化方法，此方法在過濾器初始化時被調用

*public void doilter(ServletRequest request , ServletResponse response,FilterChain chain)throws IOException, ServletException//對請求進行過濾處理

*public void destroy();//銷燬方法，以便釋放資源

[4]FilterConfig接口

*public Strng getFilterName();//用於獲取過濾器的名字

*public ServletContext getServletContent();//獲取Servlet上下文

*public String getInitParameter(String name);//獲取過濾器的初始化參數值

*public Enumeration getInitParameterNames();//獲取過濾器的所有初始化參數

[5]FilterChain接口

public void doFilter(ServletRequest request request, ServletResponse response)throws IOException , ServletException

[6]過濾器的配置

[html] view plain copy print ?

<filter>
<filter-name>CharactorFilter</filter-name>
<filter-class>com.lyq.CharactorFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CharactorFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>


        
                
                CharactorFilter
                
                com.lyq.CharactorFilter
                
                
                        
                        encoding
                        
                        UTF-8
                
        
        
        
                
                CharactorFilter
                
                /*

[7]實現字符亂碼過濾器處理實例

JSP文件

[html] view plain copy print ?

<body>
<form action="AddServlet" method="post">
<table align="center" border="1" width="350">
<tr>
<td class="2" align="center" colspan="2">
<h2>添加圖書信息</h2>
</td>
</tr>
<tr>
<td align="right">圖書編號：</td>
<td>
<input type="text" name="id">
</td>
</tr>
<tr>
<td align="right">圖書名稱：</td>
<td>
<input type="text" name="name">
</td>
</tr>
<tr>
<td align="right">作　　者：</td>
<td>
<input type="text" name="author">
</td>
</tr>
<tr>
<td align="right">價　　格：</td>
<td>
<input type="text" name="price">
</td>
</tr>
<tr>
<td class="2" align="center" colspan="2">
<input type="submit" value="添　加">
</td>
</tr>
</table>
</form>
</body>

添加圖書信息
圖書編號：
圖書名稱：
作　　者：
價　　格：

servlet文件

[html] view plain copy print ?

public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
//獲取PrintWriter
PrintWriter out = response.getWriter();
//獲取圖書編號
String id = request.getParameter("id");
//獲取圖書名稱
String name=request.getParameter("name");
//獲取作者
String author =request.getParameter("author");
//獲取價格
String price= request.getParameter("price");
//添加成功
out.print("<h2>圖書信息添加成功</h2><hr>");
out.print("圖書編號:"+id+"<br>");
out.print("圖書名稱:"+name+"<br>");
out.print(" 作者:"+author+"<br>");
out.print("體格:"+price+"<br>");
out.flush();//刷新流
out.close();//關閉流
}

public void doPost(HttpServletRequest request, HttpServletResponse response)
                        throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
                response.setContentType("text/html;charset=utf-8");
                //獲取PrintWriter
                PrintWriter out = response.getWriter();
                //獲取圖書編號
                String id = request.getParameter("id");
                //獲取圖書名稱
                String name=request.getParameter("name");
                //獲取作者
                String author =request.getParameter("author");
                //獲取價格
                String price= request.getParameter("price");
                //添加成功
                out.print("

圖書信息添加成功

");
                out.print("圖書編號:"+id+"

");
                out.print("圖書名稱:"+name+"

");
                out.print(" 作者:"+author+"

");
                out.print("體格:"+price+"

");
                out.flush();//刷新流
                out.close();//關閉流
        }

過濾器文件

[html] view plain copy print ?

package com.lyq;
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;
public class CharactorFilter implements Filter {
// 字符編碼
String encoding = null;
public void destroy() {
encoding = null;
}
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
// 判斷字符編碼是否爲空
if(encoding != null){
// 設置request的編碼格式
request.setCharacterEncoding(encoding);
// 設置response字符編碼
response.setContentType("text/html; charset="+encoding);
}
// 傳遞給下一過濾器
chain.doFilter(request, response);
}
public void init(FilterConfig filterConfig) throws ServletException {
// 獲取初始化參數
encoding = filterConfig.getInitParameter("encoding");
}
}

package com.lyq;
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;

public class CharactorFilter implements Filter {
        // 字符編碼
        String encoding = null;
        public void destroy() {
                encoding = null;
        }
        public void doFilter(ServletRequest request, ServletResponse response,
                        FilterChain chain) throws IOException, ServletException {
                // 判斷字符編碼是否爲空
                if(encoding != null){
                        // 設置request的編碼格式
                        request.setCharacterEncoding(encoding);
                        // 設置response字符編碼
                response.setContentType("text/html; charset="+encoding);
                }
                // 傳遞給下一過濾器
                chain.doFilter(request, response);
        }
        public void init(FilterConfig filterConfig) throws ServletException {
                // 獲取初始化參數
                encoding = filterConfig.getInitParameter("encoding");
        }
}

web配置文件

[html] view plain copy print ?

<filter>
<filter-name>CharactorFilter</filter-name>
<filter-class>com.lyq.CharactorFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CharactorFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>AddServlet</servlet-name>
<servlet-class>com.lyq.AddServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>AddServlet</servlet-name>
<url-pattern>/AddServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>

過濾器接口與實現字符編碼過濾器實…

添加圖書信息

圖書信息添加成功

一個開源且全面的C#算法實戰教程

一款.NET開源、功能強大、跨平臺的繪圖庫 - OxyPlot

CORS error 但是 status code 是200 OK

壓縮上傳的GPU數據的方案

使用skopeo同步鏡像

作爲軟件工程師，你必須知道的20個…

設計師的配色理論：你真懂這些色彩…

vc中Error spawning cl.…

對Java初學者的忠告

java Android SDK安裝與…

Mac下配置sublime實現LaTeX

https://yachay.unat.edu.pe/blog/index.php?comment_area=format_blog&comment_component=blog&comment_co

linux以太網驅動總結