從使用基於Icefaces表單認證的服務器下載文件

Question

我是ICEfaces的新手，我有一個要求，我需要從給定的URL下載文檔（http://ipaddress/formexec?objectid=201）。

此URL使用通過ICEFaces部署的基於表單的身份驗證。

我跟蹤這個URL的請求，並得到以下行：

&ice.submit.partial=false&ice.event.target=loginForm%3Aj_id33&ice.event.captured=loginForm%3Aj_id33 

是否有任何庫或代碼成功通過了用戶名和密碼下載文檔。

Answer 1

基於表單的認證與其他請求沒有多大區別。你所要做的就是向驗證表單提交一個請求，提供必要的參數，例如用戶名和密碼，在某些情況下，你必須從源頁面獲得額外的標記。然後，您需要從身份驗證響應或會話ID參數中獲取Cookie，並將它們複製到將提取數據的下一個請求。

Answer 2

您需要從Set-Cookie響應標頭中提取jsessionid，並將其作爲URL屬性附加到後續請求中作爲http://example.com/path/page.jsf;jsessionid=XXX。

這裏有一個開球例如與「普通的香草」 java.net.URLConnection的幫助：

// Prepare stuff. 
String loginurl = "http://example.com/login"; 
String username = "itsme"; 
String password = "youneverguess"; 
URLConnection connection = null; 
InputStream response = null; 

// First get jsessionid (do as if you're just opening the login page). 
connection = new URL(loginurl).openConnection(); 
response = connection.getInputStream(); // This will actually send the request. 
String cookie = connection.getHeaderField("Set-Cookie"); 
String jsessionid = cookie.split(";")[0].split("=")[1]; // This assumes JSESSIONID is first field (normal case), you may need to change/finetune it. 
String jsessionidurl = ";jsessionid=" + jsessionid; 
response.close(); // We're only interested in response header. Ignore the response body. 

// Now do login. 
String authurl = loginurl + "/j_security_check" + jsessionidurl; 
connection = new URL(authurl).openConnection(); 
connection.setDoOutput(true); // Triggers POST method. 
PrintWriter writer = new PrintWriter(new OutputStreamWriter(connection.getOutputStream())); 
writer.write("j_username=" + URLEncoder.encode(username, "UTF-8") 
      + "&j_password=" + URLEncoder.encode(password, "UTF-8")); 
writer.close(); 
response = connection.getInputStream(); // This will actually send the request. 
response.close(); 

// Now you can do any requests in the restricted area using jsessionid. E.g. 
String downloadurl = "http://example.com/download/file.ext" + jsessionidurl; 
InputStream download = new URL(downloadurl).openStream(); 
// ... 

爲了實現用更少的臃腫的代碼相同，考慮Apache Commons HttpComponents Client。