Pseudocode for callback demonstration

Package COM. jadyer. callback; </P> <p>/** <br/> * the pseudo <SPAN class = 'wp _ keywordlink '> Code </span> <br/> * of the callback demo the class is equivalent to the application <SPAN class = 'wp _ keywordlink'> Program </span> <br/> */<br/> public class callbackdemo {<br /> Public static void main (string [] ARGs) {<br/> persistmanager = new persistmanager (); <br/> persistmanager. persist (New hibernatecallback () {<br/> Public object doinhibernate (Session sess Ion) throws hibernateexception, sqlexception {<br/> User user = new user (); <br/> User. setusername (""); <br/> User. setpassword ("Dust Removal"); <br/> session. save (User); <br/>}< br/> }); <br/>}</P> <p>/** <br/> * persistence management class <br/> */<br/> class persistmanager {<br/> // The persist(resumable upload is equivalent to gethibernatetemplate(cmd.exe cutefind () method <br/> // they must also receive a hibernatecallback object <br/> Public void persist (hibernatecallback Act Ion) {<br/> session = NULL; <br/> try {<br/> session = hibernateutils. getsession (); <br/> session. begintrasaction (); </P> <p> // when doinhibernate (Session) is executed, pass the session to <br/> // so we can get the session directly in the anonymous class and use the action directly. <br/>. doinhibernate (session); // callback </P> <p> session. gettransaction (). commit (); <br/>}catch (exception e) {<br/> session. gettransaction (). rollback (); <br/>}finally {<br/> hibernateutils. c Losesession (session); <br/>}</P> <p>/** <br/> * The interface defined here, for the moment, make it the same name and method as the hibernatecallback interface of spring <br/> */<br/> interface hibernatecallback {<br/> Object doinhibernate (session) throws hibernateexception, sqlexception; <br/>}</P> <p>/************** [callback function ]********* **************************************** * **********/<br/> // callback function: optimize the code to reduce the template. It can extract some template statements <br/> // when writing JDBC or hibernate, you need to get the session, start and commit the transaction, try {} catch {}, roll back, and so on. <br/> // we used to solve the problem through dynamic proxy, switch it into the code. In fact, you can also use the callback mechanism to solve similar problems <br/>/*************** [Use of callback ]******* **************************************** * ***********/<br/> // by calling the persistence method of the persistence manager, persistmanager is called. for example, <br/> // persist () needs to pass an object that implements the hibernatecallback interface, here we also use the anonymous method <br/> // Since the hibernatecallback interface is implemented, the doinhibernate () interface must be implemented in the anonymous class () method <br/> // because the parameter of doinhibernate () method is session, we can get the session when implementing this method. <br/> // after obtaining the session, then we can do the relevant processing. assume that we have a new user and then use session to save the user, and so on <br/>/************* [callback details ]**************** **************************************** * ***/<br/> // for how to obtain the session and enable the transaction, transaction rollback, commit, and session shutdown are all ignored. <br/> // These template-based codes are all managed in persist (). When we call persistmanager. during the persist () method <br/> // The persistmanager is actually called. java Management class, and then we can do relevant things in the management class <br/> // we can write the template-based code to persistmanager. in Java, <br/> // In the persist () method can reduce the number of template class code. Instead, we only encapsulate the code into persistmanager. <br/> /****************************** **************************************** ****************/