Developing the Business Logic Layer

The business logic of the application is represented with a session bean named Project Facade. You need to create a separate Java package that stores the session bean and then manually add the implementation that is required.

Procedure

From the context menu of the app_ejb, choose New EJB Session Bean 3.0 .
Enter the following package name com.sap.nwce.ra.sedm.ejb.service .
Enter ProjectFacade for the EJB class name and choose Finish.
Inject a persistence manager field to use the Entity Manager.
Syntax
1. ```
@PersistenceContext(unitName = "ems/EJB3_simpl_EDM_DEMO_PU")
    protected EntityManager em;
```
End of the code.
With the Entity Manager you can effectively and easily manage your application entities.

Add the following implementation:

Syntax Syntax

public List< Project> findProjects(String nameDescrPtrn){
		Query q = ("".equals(nameDescrPtrn)) ? 
			em.createNamedQuery( "Project.getAll" ) : 
			em.createNamedQuery( "Project.findByNameOrDescPart" ) ;

		if  ( ! "".equals(nameDescrPtrn)){
			q.setParameter("namepart", "%" + nameDescrPtrn + "%");
			q.setParameter("namepart1", "%" + nameDescrPtrn + "%");
		}

		return q.getResultList();
	}

	public List< Employee> findEmployees(String nameDescrPtrn){
		Query q = ("".equals(nameDescrPtrn)) ? 
			em.createNamedQuery( "Employee.getAll" ) : 
			em.createNamedQuery( "Employee.findByNamePart" ) ;

		if  ( ! "".equals(nameDescrPtrn)){
			q.setParameter("namepart", "%" + nameDescrPtrn + "%");
			q.setParameter("namepart1", "%" + nameDescrPtrn + "%");
		}

		return q.getResultList();
	}

	public void saveProject(Project proj){
		em.merge(proj);
	}

	public void saveEmployee(Employee empl){
		em.merge(empl);
	}

	public Project getProjectById(int id){
		Query q = em.createNamedQuery( "Project.getByProjectID" ); 
		q.setParameter("prjId", id);
		return (Project) q.getSingleResult();

	}

	public Employee getEmployeeById(int id){
		Query q = em.createNamedQuery( "Employee.getById" ); 
		q.setParameter("id", id);
		return (Employee) q.getSingleResult();

	}

End of the code.

From the secondary mouse button, select Source Organize Imports javax.persistence.Query java.util.List .
Add all the methods to local interface by choosing the corresponding method from the Outline view, then from its context menu choose EJB methods—> Add to local Interfaces.