CAS的作用是負(fù)責(zé)單點(diǎn)登錄，登錄細(xì)節(jié)當(dāng)然要自己寫，CAS3有一個(gè)這樣的AuthenticationHandler 接口，繼承關(guān)系如下
1，AbstractAuthenticationHandler implements AuthenticationHandler
2，AbstractUsernamePasswordAuthenticationHandler extends AbstractAuthenticationHandler
AbstractUsernamePasswordAuthenticationHandler 正是你認(rèn)證管理的著手點(diǎn)，你寫一個(gè)類，如WeblogicAuthenticanHandler去擴(kuò)展它。
你先看看下面的接口：
public interface AuthenticationHandler {
/**
* Method to determine if the credentials supplied can be authenticated.
*
* @param credentials The credentials to authenticate
* @return true if authenticated and false they are not
* @throws AuthenticationException An AuthenticationException can contain details about why a particular authentication request failed.
* AuthenticationExceptions contain code/desc.
*/
boolean authenticate(Credentials credentials) throws AuthenticationException;
}
authenticate這個(gè)接口是每個(gè)Hander都必須實(shí)現(xiàn)，當(dāng)然，AbstractHandler將它轉(zhuǎn)交給 authenticateInternal 方法去實(shí)現(xiàn)。
認(rèn)證有兩種情況，成功或者失敗，true or false。
我使用Weblogic的LoginModule
loginContext = new LoginContext("WeblogicUsernamePasswordModule", new WeblogicCallbackHandler(username, password, url));
它拋出個(gè)各種不同的認(rèn)證異常讓我輕松判斷認(rèn)證過程中發(fā)生了什么事情，
/**
* Attempt authentication
*/
try
{
// If we return without an exception, authentication succeeded
loginContext.login();
}
catch(FailedLoginException fle)
{
System.out.println("Authentication Failed, " + fle.getMessage());
loginsccess=false;
}
catch(AccountExpiredException aee)
{
System.out.println("Authentication Failed: Account Expired");
loginsccess=false;
}
catch(CredentialExpiredException cee)
{
System.out.println("Authentication Failed: Credentials Expired");
loginsccess=false;
}
catch(Exception e)
{
System.out.println("Authentication Failed: Unexpected Exception, " + e.getMessage());
loginsccess=false;
}
如果一切正常，授權(quán)開始了。
if(loginsccess==true)
{
/**
* Retrieve authenticated subject, perform SampleAction as Subject
*/
subject = loginContext.getSubject();
System.out.println("User["+ username+"]["+ password+"] Login Success, Subject is"+subject.toString());
return true;
}
else
{
System.out.println("User["+ username+"]["+ password+"] Login Fail, Check!!!!!");
return false;
}
OK，獲得了Subject，那你就可以獲得principal，編程式授權(quán)便有了依據(jù)。
同時(shí)，你還可以用Weblogic的聲明式授權(quán)，直接在web.xml中定義資源的授權(quán)規(guī)則。
更多關(guān)于認(rèn)證授權(quán)，請(qǐng)看[Weblogic Security In Action]
http://dev2dev.bea.com.cn/bbs/servlet/D2DServlet/download/81-26770-158358-1697/WeblogicSecurityInAction(1).swf