web网页获取，cookie 的管理，post和get方式的模拟。

web登陆无非就是网页获取，cookie 的管理，post和get方式的模拟。 

1.网页内容获取 
java.io.inputstream in; 
java.net.url url = new java.net.url(www.xyz.com/content.html); 
java.net.httpurlconnection connection = (java.net.httpurlconnection) 
url.openconnection(); 
connection = (java.net.httpurlconnection) url.openconnection(); 
//模拟成ie 
connection.setrequestproperty("user-agent","mozilla/4.0 (compatible; msie 6.0; windows 2000)"); 
connection.connect(); 
in = connection.getinputstream(); 
java.io.bufferedreader breader = 
new bufferedreader(new inputstreamreader(in , "gbk")); 
string str=breader.readline()); 
while(st != null){ 
system.out.println(str); 
str=breader.readline()); 
} 
2.cookie管理 

1.直接的方式 
取得cookie： 
httpurlconnection huc= (httpurlconnection) url.openconnection(); 
inputstream is = huc.getinputstream(); 
// 取得sessionid. 
string cookieval = hc.getheaderfield("set-cookie"); 
string sessionid; 
if(cookieval != null) 
{ 
sessionid = cookieval.substring(0, cookieval.indexof(";")); 
} 

发送设置cookie： 
httpurlconnection huc= (httpurlconnection) url.openconnection(); 
if(sessionid != null) 
{ 
huc.setrequestproperty("cookie", sessionid); 
} 
inputstream is = huc.getinputstream(); 



2.利用的jcookie包(http://jcookie.sourceforge.net/ ) 
获取cookie: 
url url = new url("http://www.site.com/"); 
httpurlconnection huc = (httpurlconnection) url.openconnection(); 
huc.connect(); 
inputstream is = huc.getinputstream(); 
client client = new client(); 
cookiejar cj = client.getcookies(huc); 


新的请求,利用上面获取的cookie: 

url = new url("http://www.site.com/"); 
huc = (httpurlconnection) url.openconnection(); 
client.setcookies(huc, cj); 


3.post方式的模拟 
url url = new url("www.xyz.com"); 
httpurlconnection huc = (httpurlconnection) url.openconnection(); 
//设置允许output 
huc.setdooutput(true); 
//设置为post方式 
huc.setrequestmethod("post"); 
huc.setrequestproperty("user-agent","mozilla/4.7 [en] (win98; i)"); 
stringbuffer sb = new stringbuffer(); 
sb.append("username="+usernme); 
sb.append("&password="+password); 

//post信息 
outputstream os = huc.getoutputstream(); 
os.write(sb.tostring().getbytes("gbk")); 
os.close(); 

bufferedreader br = new bufferedreader(new inputstreamreader(huc.getinputstream())) 


huc.connect(); 

string line = br.readline(); 

while(line != null){ 

l 

system.out.printli(line); 


line = br.readline(); 

}