如何在Bean中使用cookie？

[lwwwp]

没有request

[Reason_Bbx]

/*
* CookieBean.java
* Created 2003/1/7 9:00 PM
* EditBy [e-mail]
* CopyRight Sans 2003
*/

package test001;

import java.beans.*;
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class CookieBean extends HttpServlet {

public CookieBean() {
}

public void addCookie(HttpServletResponse res, String cookieName, String cookieValue) {
Cookie c = new Cookie(cookieName, cookieValue);
res.addCookie(c);
}

public void setCookieMaxAge(HttpServletRequest req, HttpServletResponse res, String cookieName, int cookieExpires) {
Cookie c[] = req.getCookies();
if (c != null) {
for (int i = 0; i < c.length; i++) {
if (c[i].getName().equals(cookieName)) {
c[i].setMaxAge(cookieExpires);
res.addCookie(c[i]);
}
}
}
}

public int getCookieMaxAge(HttpServletRequest req, String cookieName) {
Cookie c[] = req.getCookies();
if (c != null) {
for (int i = 0; i < c.length; i++) {
if (c[i].getName().equals(cookieName)) {
return c[i].getMaxAge();
}
}
}
return -1;
}

public String getCookieValue (HttpServletRequest req, String cookieName) {
Cookie c[] = req.getCookies();
if (c != null) {
for (int i = 0; i < c.length; i++) {
if (c[i].getName().equals(cookieName)) {
return c[i].getValue();
}
}
}
return "";
}

public void setCookieValue (HttpServletRequest req, HttpServletResponse res, String cookieName, String cookieValue) {
Cookie c[] = req.getCookies();
if (c != null) {
for (int i = 0; i < c.length; i++) {
if (c[i].getName().equals(cookieName)) {
c[i].setValue(cookieValue);
res.addCookie(c[i]);
}
}
}
}
}

[Reason_Bbx]

1、
test_cookie.jsp
<!--
Created 2003/1/7 9:00 PM
EditBy [e-mail]
CopyRight Sans 2003
-->
<%@page import="test001.CookieBean"%>
<%
CookieBean cookie = new CookieBean();
cookie.addCookie(response,"cookie_001","I'm cookie 001 !");
cookie.addCookie(response,"cookie_002","I'm cookie 002 !");
cookie.addCookie(response,"cookie_003","I'm cookie 003 !");
%>
<P>
创建 cookie
<A HREF="test_cookie_002.jsp">取 cookie 值</A>

2、
test_cookie_002.jsp
<!--
Created 2003/1/7 9:00 PM
EditBy [e-mail]
CopyRight Sans 2003
-->
<%@page import="test001.CookieBean"%>
<%
CookieBean cookie = new CookieBean();
String cookie_001 = cookie.getCookieValue(request,"cookie_001");
String cookie_002 = cookie.getCookieValue(request,"cookie_002");
String cookie_003 = cookie.getCookieValue(request,"cookie_003");

cookie.setCookieValue(request,response,"cookie_001","The master changed my value to No. 1 !");

cookie.setCookieMaxAge(request,response,"cookie_002",0); // delete cookie_002
cookie.setCookieMaxAge(request,response,"cookie_003",1000);

int cookie_002_MaxAge = cookie.getCookieMaxAge(request,"cookie_002");
int cookie_003_MaxAge = cookie.getCookieMaxAge(request,"cookie_003");
%>
<BR> cookie_001 = <%= cookie_001 %>
<BR> cookie_002 = <%= cookie_002 %>
<BR> cookie_003 = <%= cookie_003 %>
<BR> cookie_002_MaxAge = <%= cookie_002_MaxAge %> 秒
<BR> cookie_003_MaxAge = <%= cookie_003_MaxAge %> 秒

<P>

<A HREF="test_cookie_003.jsp">更改 cookie_001 的值</A>

3、
test_cookie_003.jsp
<!--
Created 2003/1/7 9:00 PM
EditBy [e-mail]
CopyRight Sans 2003
-->
<%@page import="test001.CookieBean"%>
<%
CookieBean cookie = new CookieBean();
String cookie_001 = cookie.getCookieValue(request,"cookie_001");
String cookie_002 = cookie.getCookieValue(request,"cookie_002");
String cookie_003 = cookie.getCookieValue(request,"cookie_003");
%>
<BR> cookie_001 = <%= cookie_001 %>
<BR> cookie_002 = <%= cookie_002 %>
<BR> cookie_003 = <%= cookie_003 %>
<P>

<A HREF="test_cookie.jsp">从头演示</A>


这是我用上面的bean来做的演示！看完了你应该知道在bean中使用cookie的方法了。。。

[lwwwp]

to Reason_Bbx(金龙鱼):
好像不能解决我的问题：
由于特殊系统的需求，使用的数据库由用户首先选择
我把用户选择的数据库名记录在cookie中
那么，在打开数据的javabean里就要调用这个cookie

对于这个问题，有没有好办法？

[zxhong]

http://www.csdn.net/develop/Read_Article.asp?Id=9903

[lwwwp]

request.getCookies()读出Cookie

问题就是在连接数据库的javabean（DatabaseConnection.java）中怎么有request？

[lwwwp]

没有办法了吗？