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一、什么是HTTP协议
HTTP是hypertext transfer protocol(超文本传输协议)的简写,它是TCP/IP协议的一个应用层协议,用于定义WEB浏览器与WEB服务器之间交换数据的过程。客户端连上web服务器后,若想获得web服务器中的某个web资源,需遵守一定的通讯格式,HTTP协议用于定义客户端与web服务器通迅的格式。
二、HTTP协议的版本
HTTP协议的版本:HTTP/1.0、HTTP/1.1
三、HTTP1.0和HTTP1.1的区别
在HTTP1.0协议中,客户端与web服务器建立连接后,只能获得一个web资源。
在HTTP1.1协议,允许客户端与web服务器建立连接后,在一个连接上获取多个web资源。
四、HTTP请求
4.1、HTTP请求包括的内容
客户端连上服务器后,向服务器请求某个web资源,称之为客户端向服务器发送了一个HTTP请求。
一个完整的HTTP请求包括如下内容:一个请求行、若干消息头、以及实体内容
范例:
4.2、HTTP请求的细节——请求行
请求行中的GET称之为请求方式,请求方式有:POST、GET、HEAD、OPTIONS、DELETE、TRACE、PUT,常用的有: GET、 POST
用户如果没有设置,默认情况下浏览器向服务器发送的都是get请求,例如在浏览器直接输地址访问,点超链接访问等都是get,用户如想把请求方式改为post,可通过更改表单的提交方式实现。
不管POST或GET,都用于向服务器请求某个WEB资源,这两种方式的区别主要表现在数据传递上:如果请求方式为GET方式,则可以在请求的URL地址后以?的形式带上交给服务器的数据,多个数据之间以&进行分隔,例如:GET /mail/1.html?name=abc&password=xyz HTTP/1.1
GET方式的特点:在URL地址后附带的参数是有限制的,其数据容量通常不能超过1K。
如果请求方式为POST方式,则可以在请求的实体内容中向服务器发送数据,Post方式的特点:传送的数据量无限制。
4.3、HTTP请求的细节——消息头
HTTP请求中的常用消息头
- accept:——浏览器通过这个头告诉服务器,它所支持的数据类型
- Accept-Charset: ——浏览器通过这个头告诉服务器,它支持哪种字符集
- Accept-Encoding:——浏览器通过这个头告诉服务器,支持的压缩格式
- Accept-Language:——浏览器通过这个头告诉服务器,它的语言环境
- Host:——浏览器通过这个头告诉服务器,想访问哪台主机
- If-Modified-Since:—— 浏览器通过这个头告诉服务器,缓存数据的时间
- Referer:——浏览器通过这个头告诉服务器,客户机是哪个页面来的 防盗链
- Connection:——浏览器通过这个头告诉服务器,请求完后是断开链接还是何持链接
例如:
<code class="hljs lasso has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;">Accept: application/x<span class="hljs-attribute" style="box-sizing: border-box;">-ms</span><span class="hljs-attribute" style="box-sizing: border-box;">-application</span>, image/jpeg, application/xaml<span class="hljs-subst" style="color: rgb(0, 0, 0); box-sizing: border-box;">+</span><span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">xml</span>, image/gif, image/pjpeg,
application/x<span class="hljs-attribute" style="box-sizing: border-box;">-ms</span><span class="hljs-attribute" style="box-sizing: border-box;">-xbap</span>, application/vnd<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">.</span>ms<span class="hljs-attribute" style="box-sizing: border-box;">-excel</span>, application/vnd<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">.</span>ms<span class="hljs-attribute" style="box-sizing: border-box;">-powerpoint</span>, application/msword, <span class="hljs-subst" style="color: rgb(0, 0, 0); box-sizing: border-box;">*</span><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">/*
Referer: http://localhost:8080/JavaWebDemoProject/Web/2.jsp
Accept-Language: zh-CN
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; InfoPath.3)
Accept-Encoding: gzip, deflate
Host: localhost:8080
Connection: Keep-Alive</span></code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li></ul>
五、HTTP响应
5.1、HTTP响应包括的内容
一个HTTP响应代表服务器向客户端回送的数据,它包括: 一个状态行、若干消息头、以及实体内容 。
范例:
<code class="hljs http has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-status" style="color: rgb(0, 0, 136); box-sizing: border-box;">HTTP/1.1 <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200</span> OK</span>
<span class="hljs-attribute" style="box-sizing: border-box;">Server</span>: <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">Apache-Coyote/1.1</span>
<span class="hljs-attribute" style="box-sizing: border-box;">Content-Type</span>: <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">text/html;charset=ISO-8859-1</span>
<span class="hljs-attribute" style="box-sizing: border-box;">Content-Length</span>: <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">105</span>
<span class="hljs-attribute" style="box-sizing: border-box;">Date</span>: <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">Tue, 27 May 2014 16:23:28 GMT</span>
<span class="xml" style="box-sizing: border-box;"><span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"><<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">html</span>></span>
<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"><<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">head</span>></span>
<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"><<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">title</span>></span>Hello World JSP<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"></<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">title</span>></span>
<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"></<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">head</span>></span>
<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"><<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">body</span>></span>
Hello World!
<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"></<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">body</span>></span>
<span class="hljs-tag" style="color: rgb(0, 102, 102); box-sizing: border-box;"></<span class="hljs-title" style="box-sizing: border-box; color: rgb(0, 0, 136);">html</span>></span></span></code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li></ul>
5.2、HTTP响应的细节——状态行
状态行格式: HTTP版本号 状态码 原因叙述<CRLF>
举例:HTTP/1.1 200 OK
状态码用于表示服务器对请求的处理结果,它是一个三位的十进制数。响应状态码分为5类,如下所示:
5.3、HTTP响应细节——常用响应头
HTTP响应中的常用响应头(消息头)
- Location: 服务器通过这个头,来告诉浏览器跳到哪里
- Server:服务器通过这个头,告诉浏览器服务器的型号
- Content-Encoding:服务器通过这个头,告诉浏览器,数据的压缩格式
- Content-Length: 服务器通过这个头,告诉浏览器回送数据的长度
- Content-Language:服务器通过这个头,告诉浏览器语言环境
- Content-Type:服务器通过这个头,告诉浏览器回送数据的类型
- Refresh:服务器通过这个头,告诉浏览器定时刷新
- Content-Disposition:服务器通过这个头,告诉浏览器以下载方式打数据
- Transfer-Encoding:服务器通过这个头,告诉浏览器数据是以分块方式回送的
- Expires: -1 控制浏览器不要缓存
- Cache-Control: no-cache
- Pragma:no-cache
六、在服务端设置响应头来控制客户端浏览器的行为
6.1、设置Location响应头,实现请求重定向
<code class="hljs java has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">package</span> gacl.http.study;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.IOException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.ServletException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServlet;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletRequest;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletResponse;
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @author</span> gacl
*
*/</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ServletDemo01</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">HttpServlet</span> {</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doGet</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
response.setStatus(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">302</span>);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//设置服务器的响应状态码</span>
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
*设置响应头,服务器通过 Location这个头,来告诉浏览器跳到哪里,这就是所谓的请求重定向
*/</span>
response.setHeader(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Location"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"/JavaWeb_HttpProtocol_Study_20140528/1.jsp"</span>);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doPost</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.doGet(request, response);
}
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li></ul>
当在浏览器中使用URL地址”http://localhost:8080/JavaWeb_HttpProtocol_Study_20140528/servlet/ServletDemo01“访问ServletDemo01时,就可以看到服务器作出响应后发送到浏览器的状态码和响应头信息,如下图所示:
服务器返回一个302状态码告诉浏览器,你要的资源我没有,但是我通过Location响应头告诉你哪里有,而浏览器解析响应头Location后知道要跳转到/JavaWeb_HttpProtocol_Study_20140528/1.jsp页面,所以就会自动跳转到1.jsp,如下图所示:
6.2、设置Content-Encoding响应头,告诉浏览器数据的压缩格式
<code class="hljs java has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">package</span> gacl.http.study;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.ByteArrayOutputStream;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.IOException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.util.zip.GZIPOutputStream;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.ServletException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServlet;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletRequest;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletResponse;
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
*<span class="hljs-javadoctag" style="color: rgb(102, 0, 102); box-sizing: border-box;"> @author</span> gacl
*这个小程序是用来演示以下两个小知识点
*1、使用GZIPOutputStream流来压缩数据
*2、设置响应头Content-Encoding来告诉浏览器,服务器发送回来的数据压缩后的格式
*/</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ServletDemo02</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">HttpServlet</span> {</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doGet</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
String data = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"abcdabcdabcdabcdabcdabcdab"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"cdabcdabcdabcdabcdabcdabcdabcdabc"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"dabcdabcdabcdabcdabcdabcdabcdabc"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"dabcdabcdabcdabcdabcdabcdabcdabcdab"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"cdabcdabcdabcdabcdabcdabcdabcdabcdab"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"cdabcdabcdabcdabcdabcdabcdabcdabcdab"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"cdabcdabcdabcdabcdabcdabcdabcdabcdab"</span> +
<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"cdabcdabcdabcdabcdabcdabcdabcdabcdabcd"</span>;
System.out.println(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"原始数据的大小为:"</span> + data.getBytes().length);
ByteArrayOutputStream bout = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> ByteArrayOutputStream();
GZIPOutputStream gout = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> GZIPOutputStream(bout); <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//buffer</span>
gout.write(data.getBytes());
gout.close();
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//得到压缩后的数据</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">byte</span> g[] = bout.toByteArray();
response.setHeader(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Content-Encoding"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"gzip"</span>);
response.setHeader(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"Content-Length"</span>,g.length +<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">""</span>);
response.getOutputStream().write(g);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doPost</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.doGet(request, response);
}
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li><li style="box-sizing: border-box; padding: 0px 5px;">39</li><li style="box-sizing: border-box; padding: 0px 5px;">40</li><li style="box-sizing: border-box; padding: 0px 5px;">41</li><li style="box-sizing: border-box; padding: 0px 5px;">42</li><li style="box-sizing: border-box; padding: 0px 5px;">43</li><li style="box-sizing: border-box; padding: 0px 5px;">44</li><li style="box-sizing: border-box; padding: 0px 5px;">45</li></ul>
服务器发给浏览器的响应信息如下:
浏览器支持的压缩格式有:
6.3、设置content-type响应头,指定回送数据类型
<code class="hljs java has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">package</span> gacl.http.study;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.IOException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.InputStream;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.OutputStream;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.ServletException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServlet;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletRequest;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletResponse;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ServletDemo03</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">HttpServlet</span> {</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doGet</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* 浏览器能接收(Accept)的数据类型有:
* application/x-ms-application,
* image/jpeg,
* application/xaml+xml,
* image/gif,
* image/pjpeg,
* application/x-ms-xbap,
* application/vnd.ms-excel,
* application/vnd.ms-powerpoint,
* application/msword,
*/</span>
response.setHeader(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"content-type"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"image/jpeg"</span>);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//使用content-type响应头指定发送给浏览器的数据类型为"image/jpeg"</span>
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//读取位于项目根目录下的img文件夹里面的WP_20131005_002.jpg这张图片,返回一个输入流</span>
InputStream in = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.getServletContext().getResourceAsStream(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"/img/WP_20131005_002.jpg"</span>);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">byte</span> buffer[] = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">byte</span>[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1024</span>];
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> len = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>;
OutputStream out = response.getOutputStream();<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//得到输出流</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">while</span> ((len = in.read(buffer)) > <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) {<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//读取输入流(in)里面的内容存储到缓冲区(buffer)</span>
out.write(buffer, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, len);<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//将缓冲区里面的内容输出到浏览器</span>
}
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doPost</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.doGet(request, response);
}
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li><li style="box-sizing: border-box; padding: 0px 5px;">34</li><li style="box-sizing: border-box; padding: 0px 5px;">35</li><li style="box-sizing: border-box; padding: 0px 5px;">36</li><li style="box-sizing: border-box; padding: 0px 5px;">37</li><li style="box-sizing: border-box; padding: 0px 5px;">38</li></ul>
服务器发给浏览器的响应信息如下:
ServletDemo03的运行结果如下图所示:
在浏览器中显示出了图片
6.4、设置refresh响应头,让浏览器定时刷新
<code class="hljs java has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">package</span> gacl.http.study;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.IOException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.ServletException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServlet;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletRequest;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletResponse;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ServletDemo04</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">HttpServlet</span> {</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doGet</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* 设置refresh响应头,让浏览器每隔3秒定时刷新
*/</span>
<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">// response.setHeader("refresh", "3");</span>
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* 设置refresh响应头,让浏览器3秒后跳转到http://www.baidu.com
*/</span>
response.setHeader(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"refresh"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"3;url='http://www.baidu.com'"</span>);
response.getWriter().write(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"gacl"</span>);
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doPost</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.doGet(request, response);
}
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li></ul>
6.5、设置content-disposition响应头,让浏览器下载文件
<code class="hljs java has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">package</span> gacl.http.study;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.IOException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.InputStream;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> java.io.OutputStream;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.ServletException;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServlet;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletRequest;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">import</span> javax.servlet.http.HttpServletResponse;
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-class" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">class</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">ServletDemo05</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">extends</span> <span class="hljs-title" style="box-sizing: border-box; color: rgb(102, 0, 102);">HttpServlet</span> {</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doGet</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/**
* 设置content-disposition响应头,让浏览器下载文件
*/</span>
response.setHeader(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"content-disposition"</span>, <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"attachment;filename=xxx.jpg"</span>);
InputStream in = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.getServletContext().getResourceAsStream(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"/img/1.jpg"</span>);
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">byte</span> buffer[] = <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">new</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">byte</span>[<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1024</span>];
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> len = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>;
OutputStream out = response.getOutputStream();
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">while</span> ((len = in.read(buffer)) > <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>) {
out.write(buffer, <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>, len);
}
}
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">public</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">void</span> <span class="hljs-title" style="box-sizing: border-box;">doPost</span>(HttpServletRequest request, HttpServletResponse response)
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">throws</span> ServletException, IOException {
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.doGet(request, response);
}
}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li><li style="box-sizing: border-box; padding: 0px 5px;">13</li><li style="box-sizing: border-box; padding: 0px 5px;">14</li><li style="box-sizing: border-box; padding: 0px 5px;">15</li><li style="box-sizing: border-box; padding: 0px 5px;">16</li><li style="box-sizing: border-box; padding: 0px 5px;">17</li><li style="box-sizing: border-box; padding: 0px 5px;">18</li><li style="box-sizing: border-box; padding: 0px 5px;">19</li><li style="box-sizing: border-box; padding: 0px 5px;">20</li><li style="box-sizing: border-box; padding: 0px 5px;">21</li><li style="box-sizing: border-box; padding: 0px 5px;">22</li><li style="box-sizing: border-box; padding: 0px 5px;">23</li><li style="box-sizing: border-box; padding: 0px 5px;">24</li><li style="box-sizing: border-box; padding: 0px 5px;">25</li><li style="box-sizing: border-box; padding: 0px 5px;">26</li><li style="box-sizing: border-box; padding: 0px 5px;">27</li><li style="box-sizing: border-box; padding: 0px 5px;">28</li><li style="box-sizing: border-box; padding: 0px 5px;">29</li><li style="box-sizing: border-box; padding: 0px 5px;">30</li><li style="box-sizing: border-box; padding: 0px 5px;">31</li><li style="box-sizing: border-box; padding: 0px 5px;">32</li><li style="box-sizing: border-box; padding: 0px 5px;">33</li></ul>
在浏览器中访问ServletDemo05就会弹出文件下载框,如下图所示:
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