My initial understanding of Shiro

 PackageCom.shiro;Importorg.apache.shiro.SecurityUtils;ImportOrg.apache.shiro.authc.*;Importorg.apache.shiro.config.IniSecurityManagerFactory;ImportOrg.apache.shiro.mgt.SecurityManager;Importorg.apache.shiro.session.Session;Importorg.apache.shiro.subject.PrincipalCollection;ImportOrg.apache.shiro.subject.Subject;Importorg.apache.shiro.util.Factory;ImportOrg.slf4j.Logger;Importorg.slf4j.LoggerFactory;/** * @since0.9 RC2*/ Public classHelloshiro {Private Static Final transientLogger log = Loggerfactory.getlogger (Helloshiro.class);  Public Static voidMain (string[] args) {//Create one of the simplest ways to configure Shiro SecurityManager//servers, users, roles, and permissions are using a simple INI configuration. //we will do it by using a factory that can ingest. INI file and//returns a SecurityManager instance://use Shiro. INI file at the root of the classpath//(file: and URL prefix payload from file and URL respectively)://1 Get a Shiro factory class based on the configuration fileFactory<securitymanager> Factory =NewInisecuritymanagerfactory ("Classpath:shiro.ini"); //2 Obtaining the Shiro Security manager in the factory classSecurityManager SecurityManager =factory.getinstance (); //3 Put the SecurityManager into the securityutilsSecurityutils.setsecuritymanager (SecurityManager); //4 using Securityutils to get the currently logged on userSubject CurrentUser =Securityutils.getsubject (); //5 Getting the current user's session state Shiro built -in sessionsSession session =currentuser.getsession (); //you can put some attributes into the session and then handle it according to your own business logic.Session.setattribute ("Somekey", "Avalue"); String value= (String) session.getattribute ("Somekey"); if(Value.equals ("Avalue") {log.info ("Retrieved the correct value! ["+ Value +"] "); }        //6 Determine if the current user has authenticated        if(!currentuser.isauthenticated ()) {System.out.println ("Current user is not logged in---->"); //7 Impersonation Create a login tokenUsernamepasswordtoken token =NewUsernamepasswordtoken ("Lonestarr", "Vespa"); Token.setrememberme (true); Try {                //8 Sign-in Operation//Login Process//Currentuser.login (token);---> Call the Securitymanager.login (this, token) method//The login method of the---securitymanager first invokes the Authenticatingsecuritymanager authenticate (Authenticationtoken token) method /c4>//---Then the Authenticate method of Authenticatingsecuritymanager calls the doauthenticate of Modularrealmauthenticator ( Authenticationtoken Authenticationtoken)//---Then modularrealmauthenticator the DoAuthenticate method to get the config file of realm, if the profile does not define realm, the default is to use Simpleaccountrealm 
    //--If the configuration file is configured with multiple realms, traverse these realms and call the Getauthenticationinfo method in realm to get AuthenticationInfo (authentication information) to verify the current logged in user //---from the above process description, we can achieve a custom authentication method by customizing multiple realms and then overriding the Getauthenticationinfo methodCurrentuser.login (token); //principal because it is an object type, we can extend this class ourselves in real business.System.out.println ("User is logged in----> Username:" +Currentuser.getprincipal (). toString ()); } Catch(unknownaccountexception UAE) {log.info ("There is no user with username of" +Token.getprincipal ()); } Catch(Incorrectcredentialsexception ice) {Log.info ("Password for Account" + token.getprincipal () + "was incorrect!"); } Catch(Lockedaccountexception Lae) {Log.info ("The account for username" + token.getprincipal () + "is locked. "+" your administrator to unlock it. "); }            Catch(Authenticationexception ae) {}}//9 Determine the role of the currently logged on user---//as can be seen from the source code, Currentuser.hasrole ("Schwartz")---Call the method of Securitymanager.hasrole (Getprincipals (), Roleidentifier) //then called the Authorizingrealm hasrole (principalcollection principal, String Roleidentifier) method,//Authorizingrealm's Hasrole method uses Getavailableauthorizationcache () to get authorizationinfo in the cache first, If there is no authorizationinfo in the cache//The default subclass Simpleaccountrealm Gets the Dogetauthorizationinfo method Authorizationinfo (authorization information), and the subclass Simpleaccountrealm is Factory.getinstance (), when you put the user and the role in a map,//That means we can implement our custom authentication authorization information by customizing the Authorizingrealm and then overriding the Dogetauthorizationinfo method        if(Currentuser.hasrole ("Schwartz") {log.info ("May the Schwartz is with you!"); } Else{log.info ("Hello, mere mortal."); }        //test a typed permission (not instance-level)//10 Permission Validation//from the source code it can be seen that currentuser.ispermitted ("Lightsaber:weild")---called securitymanager.ispermitted (getprincipals (), permission),//----then called Authorizingrealm's ispermitted (principalcollection principals, String permission), This method gets the default Permissionresolver, which is the parser for the permission character//the---then called Authorizingrealm. Getauthorizationinfo (), first gets the authorizationinfo in the cache, if not, then from the Simpleaccountrealm of the subclass Dogetauthorizationinfo to get authorizationinfo.//----That is, we can use the Authorizingrealm class and then implement the Dogetauthenticationinfo method to implement the authorization validation of our own business logic        if(Currentuser.ispermitted ("Lightsaber:weild") {log.info ("You could use a lightsaber ring." Use it wisely. "); } Else{log.info ("Sorry, lightsaber rings is for Schwartz Masters only."); }        //A (very powerful) Instance level permission:        if(Currentuser.ispermitted ("Winnebago:drive:eagle5") {log.info ("You're permitted to ' drive ', the Winnebago with license plate (ID) ' Eagle5 '. "+" Here is the Keys-have fun! "); } Else{log.info ("Sorry, aren ' t allowed to drive the ' eagle5 ' winnebago!"); }        //All done-log out!currentuser.logout (); System.exit (0); }}

My initial understanding of Shiro