HttpServletRequest对象方法的用法

1. 获得客户机信息

    getRequestURL方法返回客户端发出请求时的完整URL。

    getRequestURI方法返回请求行中的资源名部分。

    getQueryString 方法返回请求行中的参数部分。

    getRemoteAddr方法返回发出请求的客户机的IP地址

    getRemoteHost方法返回发出请求的客户机的完整主机名

    getRemotePort方法返回客户机所使用的网络端口号

    getLocalAddr方法返回WEB服务器的IP地址。

    getLocalName方法返回WEB服务器的主机名

    getMethod得到客户机请求方式

 2.获得客户机请求头

    getHeader(string name)方法

    getHeaders(String name)方法

    getHeaderNames方法 

 3. 获得客户机请求参数(客户端提交的数据)

    getParameter(name)方法

    getParameterValues（String name）方法

    getParameterNames方法

    getParameterMap方法

例子程序:

<span style="font-size:18px;">    public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
System.out.println("getRequestURL: "+request.getRequestURL());
System.out.println("getRequestURI: "+request.getRequestURI());
System.out.println("getQueryString: "+request.getQueryString());
System.out.println("getRemoteAddr: "+request.getRemoteAddr());
System.out.println("getRemoteHost: "+request.getRemoteHost());
System.out.println("getRemotePort: "+request.getRemotePort());
System.out.println("getRemoteUser: "+request.getRemoteUser());
System.out.println("getLocalAddr: "+request.getLocalAddr());
System.out.println("getLocalName: "+request.getLocalName());
System.out.println("getLocalPort: "+request.getLocalPort());
System.out.println("getMethod: "+request.getMethod());
System.out.println("-------request.getParamterMap()-------");
//得到请求的参数Map，注意map的value是String数组类型
Map map = request.getParameterMap();
Set<String> keySet = map.keySet();
for (String key : keySet) {
String[] values = (String[]) map.get(key);
for (String value : values) {
System.out.println(key+"="+value);
}
}
System.out.println("--------request.getHeader()--------");
//得到请求头的name集合
Enumeration<String> em = request.getHeaderNames();
while (em.hasMoreElements()) {
String name = (String) em.nextElement();
String value = request.getHeader(name);
System.out.println(name+"="+value);
}

}  </span>

浏览器上地址栏：http://localhost:8080/RequestAndResponse/requestmethod?name=sunjob&password=123456&password=haha
控制台输出：

getRequestURL: http://localhost:8080/RequestAndResponse/requestmethod getRequestURI: /RequestAndResponse/requestmethod
getQueryString: name=sunjob&password=123456&password=haha
getRemoteAddr: 127.0.0.1
getRemoteHost: 127.0.0.1
getRemotePort: 2374
getRemoteUser: null
getLocalAddr: 127.0.0.1
getLocalName: localhost
getLocalPort: 8080
getMethod: GET
-------request.getParamterMap()-------
name=sunjob
password=123456
password=haha
--------request.getHeader()--------
host=localhost:8080
user-agent=Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20100101 Firefox/17.0
accept=text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
accept-language=zh-cn,en-us;q=0.8,zh;q=0.5,en;q=0.3
accept-encoding=gzip, deflate
connection=keep-alive
cache-control=max-age=0