boSession & EboContext

Each time a user logs to a XEO application a boSession instance is created to represent the session of the user whithin the application

boSession

The boSession instance

Method Name	Description	Parameters	Return type	Notes
setProperty	Sets a propery withthin the session	String key Object value	void	Property can later be retrieved with getProperty(String key)
removeProperty	Removes an existing property identified by the key parameter	String key	void
getProperty	Retrieves an existing property (or null if it does not exits)	String key	Object
getProperties	Retrieves an enumeration of all properties of this session	-	Enumeration
getPerformerIProfileName	Retrieves the name of the current profile associated to the user who created the session	-	String
getPerformerIProfileBoui	Retrieves the boui of the current profile instance associated to the user who created the session	-	long
getPerformerBoui	Returns the boui of XEO Model instance representing the user who created the session (tipically it's an instance of a XEO Model which extends the system XEO Model Ebo_Perf or the system XEO Model Interface iXEOUser)	-	long
createRequestContext	Creates a new EboContext	HttpServletRequest request, HttpServletResponse response, PageContext pagecontext	EboContext	See note*
createRequestContext	Creates a new EboContext	HttpServletRequest request, HttpServletResponse response, ServletContext servletContext	EboContext	See note*
closeSession	Closes the current session (does not destroy contexts created whithin the session)	-	void

When using XEO's Web Component Layer, the login is made through a web form which will automatically create a boSession instance for the user (and EboContext instances as well), so there's usually no need to explicitely create boSession instances, unless you're creating a custom JSP/Servlet and need to programatically connect to the XEO Application.

EboContext

Every request made to a XEO Application to load/create boObject instances must be contained in a context. EboContext is the class that implements that "context" and is where instances of boObjects are stored wheneved they are created/loaded. EboContext is also the place where transactional control can happen (there's another alternative in boObject (getUpdateQueue).Transactions created by using EboContext methods are JTA ( Java Transactional API) transactions which means you can mix DML statements with your object creation and update inside a transaction and commit on success/rollback on failure, see an example bellow.

EboContext instances are generally created by the XEO Runtime and can be accessed from several places, such as from any instance of a boObject throught the getEboContext() method. If you recall from the methods generated by XEO Studio for the required/defaultValue and such methods, one of the parameters was the boObject instance. Bellow, see the table of important methods in the EboContext class.

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Safe Ebo Context Usage Example

        boSession session = null;
        EboContext context = null;
        boApplication xeoApp = boApplication.getDefaultApplication();
        try {
                session = xeoApp.boLogin("USERNAME", "PASSWORD");        
                context = xeoApp.createContext(session);
                  
                //Your code in here

        } catch (Exception e) {
                 //Process the exception in case of error
        } finally {
            if (context!=null)
                context.close();
            if (session!=null)
                session.closeSession();
        }

Using JTA Transactions Example

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//Declare variables
        boApplication app = null;
        boSession session = null;
        EboContext ctx = null;
        
        try{
                //Get the application instance
                app = boApplication.getDefaultApplication();
                //Login a user
                session = app.boLogin("SYSUSER", "ABC");
                //Create a context
                ctx = app.createContext(session);
        
                //Start Transaction 
                ctx.beginContainerTransaction();
            
                try{
                    
                    //Create Object, set an attribute and save
                    boObject obj = app.getObjectManager().createObject(ctx, "MyObj");
                    obj.getAttribute("att").setValueString("foo");
                    obj.update();
                    
                    //Make a DML statement to insert some values in database
                    Connection conn = null;
                    Statement stmt = null;
                    
                    //Retrieve the connection and execute the query
                    conn = ctx.getConnectionData();
                    stmt = conn.createStatement(
                            ResultSet.TYPE_SCROLL_SENSITIVE,
                            ResultSet.CONCUR_READ_ONLY);
                    stmt.executeQuery("INSERT INTO MY_TABLE VALUES('foo','bar')");
                    
                    //Commit the changes
                    ctx.commitContainerTransaction();
                }
                catch (Exception e){
                    //If anything goes wrong roll back the transaction
                    ctx.rollbackContainerTransaction();
                }
        }
        catch (boRuntimeException e ){
            //Deal with the exception during execution
        } catch (boLoginException e) {
            // Deal with login exception 
        }finally{
            //Close all used resources
            if (ctx != null) ctx.close();
            if (session != null) session.closeSession();
        }

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