findAllCustomers(…)

removeTheCustomer(…)

createCustomer(…)

create()

retrieveCustData(…)

One or more

Zero or more

Exactly one

Zero

ObjectNotFoundException.

An empty Collection will be returned.

An entity would be created and a reference to that entity would be returned.

EntityNotFoundException.

The entity bean instance is deleted.

The entity in the database is deleted.

Both the entity and the entity bean instance survive, but that entity bean instance does not represent that entity anymore.

Nothing happens; the container simply ignores the call.

You cannot write JDBC code in the bean class to make a connection and send queries to any database.

You cannot write JDBC code in the bean class to change the values of virtual persistent fields of your bean.

You can write JDBC code and get connected to any database you want.

You can write JDBC code to read the virtual persistent fields, but you cannot change their values.

getEJBObject()

getPrimaryKey()

getEJBHome()

getRollbackOnly()

getUserTransaction()

All entity bean instances of the same type (say CustomerBean) have the same Home, that is, an instance of an object that implements the home interface of this bean.

A specific entity bean instance can be accessed by only one client at a time.

If two clients wanted to access the same entity in the database concurrently, the container would make two entity bean instances to represent that entity.

If two clients wanted to access the same entity in the database concurrently, the container would make one entity bean to represent that entity, and the two clients would get their own references to the same EJBObject correspondtwo clients would get their

ejbCreate

Home business methods

Business methods exposed in the component interface

ejbStore()

None of the above

234

334

2334

0123456

01234456

12334567

pc

pcc

pcp

pcpc

Compilation fails

An exception is thrown at runtime

Compilation succeeds

Compilation fails due only to an error on line 15

Compilation fails due only to an error on line 16

Compilation fails due only to an error on line 17

Compilation fails due only to an error on line 18

Compilation fails due to errors on multiple lines

8/9/05 5:54 PM

1123631685981L

An exception is thrown at runtime.

Compilation fails due to a single error in the code.

Compilation fails due to multiple errors in the code.

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.fzba

..azba

.fazba

..fezba

Compilation fails

Servlet in web application

Record in a database

Enterprise java bean

File record

A Workspace can contain multiple applications and projects ….

Module can have projects ,library and application

Library can have modules and projects

Application can have one or more projects, library and module

public void perform() { }

public boolean perform() { }

static public boolean perform() { }

public void perform() throws Exception { }

public boolean perform() throws Exception { }

Application

Library

Project

Module

Process

Protected

Private

Public

2&3

1&3

Non Static field

Base class fields

Transient Fields.

Static Field

Can have only one constructor

a.Cannot have a constructor

Can have more than one constructor

May or May not have constructors