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Showing posts from December, 2011

EJB 2.0 Drawbacks

Complex Products Unmaintainable System Non-portable, frame-work committed business components Unpredictable System Why EJB 2.0 is complex / complicated? Session bean - to write say hello method in EJB 2.x, you need to write home interface component interface bean in EJB 3.x, you need to write interface (with annotation) bean (with annotation) EJB 2.x; lookup is the only way to get server object/resource EJB 3; DI (dependency injection) & lookup are the available way there are more points. But basically, with EJB 3 responsibility of container is heavy & responsibility of developer is light weight; so that development is less & maintenance is easy.

Seam, EJB and Hibernate useful tips

  Here are some tips I have gathered during our Seam project. @Create - Signals that this method should be called upon instantiation of the JavaBean. @Stateless - Makes an EJB3 object @Stateful - (SESSION) Caches in memory between server requests @In - These variables will automatically be set by Seam through injection of the variables labeled by the annotation. i.e String zipCode; (Behind the curtain: zipCode = request.getParameter("zipCode"); ) @Out - Same as above. This variable is also automatically set by Seam. Behind the curtain this variable is set in the HttpSession object. ( request.setAttribute("bestRestaurant", restaurant); ) What you also must remember is that if you want to use the outjected object, you only call it with its name. Not component name first. i.e. If you stateful session bean is named @Name("someName") and you have a @Out String test, then when you use it in the view, you must write #{test} and not #{someName.test} You can als

Hibernate Introduction

Hibernate is a Object relational mapping framework. What it will help us is in saving the objects into the relational world. Employee.java public class Employee { private String Name; private int Emp_Id; private String Designation; private String Reportee; private int Access_Carad_No;          public String getName() {         return Name;     }     public void setName(String name) {         Name = name;     }     public int getEmp_Id() {         return Emp_Id;     }     public void setEmp_Id(int emp_Id) {         Emp_Id = emp_Id;     }     public String getDesignation() {         return Designation;     }     public void setDesignation(String designation) {         Designation = designation;     }     public String getReportee() {         return Reportee;     }     public void setReportee(String reportee) {         Reportee = reportee;     }     public int getAccess_Carad_No() {         return Access_Carad_No;     }     public void setAccess_Carad_No(int access_Carad_No) {         Acc