Package examples.ejb20.basic.beanManaged

This example is a package that demonstrates anEnterprise JavaBean.

See:
Description

Interface Summary

Account	The methods in this interface are the public face of AccountBean.
AccountHome	This interface is the home interface for the EJBean AccountBean, which in WebLogic is implemented by the code-generated container class AccountBeanC.

Class Summary

AccountBean	AccountBean is an EntityBean.
Client	This class demonstrates calling an entity EJBean.
Servlet	This servlet is a program similar to the examples.ejb20.basic.beanManaged.Client example.

Exception Summary

ProcessingErrorException

ProcessingErrorException is thrown if the caller attempts to withdraw more than a certain preset limit from the account.

Package examples.ejb20.basic.beanManaged Description

This example is a package that demonstrates anEnterprise JavaBean. The example is an entity EJBean calledAccountBean.

The example demonstrates:

• Usage of an entity EJBean
• Bean-managed persistence; the code in the EJBeandirectly accesses the data storage
• Using application-defined exceptions
• Client application
• Servlet

Pre-Built Examples

The EJB 2.0 examples included in the WebLogic Server 6.1 distribution are not shipped pre-built. To run these examples, you must build the example following the specific examples instructions.

Client application

TheClientapplication performs these steps:

1. Finds or creates 20 separate accounts
2. Prints the balances for all accounts
3. Finds all accounts with a balance greater than $5000
4. Removes the accounts

The Servletruns in a similar fashion to the Client example.Call the servlet using an appropriate URL as described in theservlet directions. See Run the example for sample servlet output.

To get the most out of this example, first read through the sourcecode files.

• Client applications
  Client.java
  Servlet.java

  Interfaces

  Account.java

  AccountHome.java

  Deployment

  ejb-jar.xml

  weblogic-ejb-jar.xml

  Exception

  ProcessingErrorException.java

  Server (EJBean)

  AccountBean.java

Start with the XML deployment files ejb-jar.xml and weblogic-ejb-jar.xml to find the general structure of the EJBean, which classes are usedfor the different objects and interfaces, then look at Client code to see how theapplication works.

As you'll use a database for the persistent storage of the entity EJBean, you'll need to set it up.Note that the persistent storage is completely invisible to the client;the actual storage is handled by the EJBean directly and not thecontainer.

These three sections cover what to do:

1. Build the example
2. Configure the server
3. Run the example

Build the example

Set up your development shell as described in Setting up your environment.

We provide separate build scripts for Windows NT and UNIX:

We provide a build script for you to build the example:

The build script is build.xml.

Run the build script using the following Java ant command:
$ant

The script will build the example and place the files in thecorrect locations in your WebLogic Server distribution:

• Client files: in /config/examples/clientclasses/
• Servlet: in /config/examples/applications/examplesWebApp/WEB-INF/Classes/
• EJBean: in /config/examples/applications/ejb_basic_beanManaged.jar

Running the build script places the EJB in /config/examples/applications, where it automatically deploys once the server is started. If you are already running the server and build another EJB, it is automatically placed in this directory and instantly deployed.

Additional information on using the build scriptsis found in Building Enterprise JavaBean examples

Configure the server

1. Start the WebLogic Server.

2. Start the Administration Console.

3. Click to expand the Deployments node in the left pane and select EJB Deployments.

   A list of deployed EJBs displays.

4. Choose the appropriate deployment unit from the list.

5. Select the Target tab in the right-hand pane.

6. Verify that the EJB is deployed on the examplesServer.

   This example contains a pre-configured servlet running in a browser called examplesWebApp.

7. Click the Web Applications node in the left-hand pane and select examplesWebApp.

8. In the right-hand pane, select the Target tab, and verify that the examplesWebApp is deployed on the examplesServer.

9. Set the database persistence.

   With database persistence, each instance of an EJBean is written to arow in a table. The table (ejbAccounts) must be created and exist in the databasebefore the example is run. If you are using the evaluationcopy of Cloudscape that is included with WebLogic, this tablehas already been created in the "demo" database. If you're using a database other than Cloudscape, you'll need tocreate the table in your database using an appropriate SQLstatement such as

   "create table ejbAccounts (id varchar(15), bal float, type varchar(15))"

10. Setup a connection pool in the Administration Console .

    For your convenience, a sample connection pool, called demoPool is included with this example. You can use this connection pool with any of the EJB examples.

    You'll need to:

    • Make sure that the connection is available for use.

      # In the left-hand pane, expand the Services node and choose JDBC.

      # Click demoPool to display the configuration information in the right-hand pane.

      # Click the Connections tab and review the attribute settings to make sure that they are correct.

    In particular, make sure that the URL and Driver Classname attributes are set for the correct database. This example connection pool is pre-configured for Cloudscape. For other databases, you will need to set an appropriate url and driver, such as

    	  URL=jdbc:weblogic:oracle,\	  DriverName=weblogic.jdbc.oci.Driver,\

    In this example, the fileRealm for the access control list (ACL) is pre-configured to allowaccess for everyone.

    If you need more information about how to use connection pools, readProgramming WebLogic JDBC.

Run the example

1. Run the client in a separate command line window. Set up your client as described in Setting up your environment,and then run the client by entering:

   $ java examples.ejb20.basic.beanManaged.Client "t3://WebLogicURL:Port"

   where:

   WebLogicURL

   Domain address of the WebLogic Server

   Port

   Port that is listening for connections(weblogic.system.ListenPort)

2. If you're running the Client example, you should get output similar to this from the client application:

   Beginning beanManaged.Client...Trying to find account with id: ID: 0Trying to find account with id: ID: 1Trying to find account with id: ID: 2Trying to find account with id: ID: 3Trying to find account with id: ID: 4Trying to find account with id: ID: 5Trying to find account with id: ID: 6Trying to find account with id: ID: 7Trying to find account with id: ID: 8Trying to find account with id: ID: 9Trying to find account with id: ID: 10Trying to find account with id: ID: 11Trying to find account with id: ID: 12Trying to find account with id: ID: 13Trying to find account with id: ID: 14Trying to find account with id: ID: 15Trying to find account with id: ID: 16Trying to find account with id: ID: 17Trying to find account with id: ID: 18Trying to find account with id: ID: 19Account: :ID: 0 has a balance of 0.0Account: :ID: 1 has a balance of 1000.0Account: :ID: 2 has a balance of 2000.0Account: :ID: 3 has a balance of 3000.0Account: :ID: 4 has a balance of 4000.0Account: :ID: 5 has a balance of 5000.0Account: :ID: 6 has a balance of 6000.0Account: :ID: 7 has a balance of 7000.0Account: :ID: 8 has a balance of 8000.0Account: :ID: 9 has a balance of 9000.0Account: :ID: 10 has a balance of 10000.0Account: :ID: 11 has a balance of 11000.0Account: :ID: 12 has a balance of 12000.0Account: :ID: 13 has a balance of 13000.0Account: :ID: 14 has a balance of 14000.0Account: :ID: 15 has a balance of 15000.0Account: :ID: 16 has a balance of 16000.0Account: :ID: 17 has a balance of 17000.0Account: :ID: 18 has a balance of 18000.0Account: :ID: 19 has a balance of 19000.0Querying for accounts with a balance greater than 5000.0...Account ID: 6; balance is $6000.0Account ID: 7; balance is $7000.0Account ID: 8; balance is $8000.0Account ID: 9; balance is $9000.0Account ID: 10; balance is $10000.0Account ID: 11; balance is $11000.0Account ID: 12; balance is $12000.0Account ID: 13; balance is $13000.0Account ID: 14; balance is $14000.0Account ID: 15; balance is $15000.0Account ID: 16; balance is $16000.0Account ID: 17; balance is $17000.0Account ID: 18; balance is $18000.0Account ID: 19; balance is $19000.0Removing beans...End beanManaged.Client...

3. If you're running the servlet example, you should get output similar to this:

   Using user user1 and password user1PasswordLooking up account 10020...Did not find 10020Account 10020 being created; opening balance is $3000.0Part A: Depositing $100.0Current balance is $3100.0Withdrawing amount greater than current balance. Expecting anexception...Received expected Processing Error:examples.ejb20.basic.beanManaged.ProcessingErrorException: Request towithdraw $3110.0 more than balance 3100.0 in account 10020Part B: Creating 5 new accounts...Created account: 9543031558300; balance is $0.0Created account: 9543031558301; balance is $100.0Created account: 9543031558302; balance is $200.0Created account: 9543031558303; balance is $300.0Created account: 9543031558304; balance is $400.05 accounts successfully createdQuerying for accounts with a balance greater than 200.0...Account 10020; balance is $3100.0Account 9543031558303; balance is $300.0Account 9543031558304; balance is $400.0Removing accounts just created...Removed account: 9543031558300Removed account: 9543031558301Removed account: 9543031558302Removed account: 9543031558303Removed account: 9543031558304End beanManaged.Servlet...

There's more...

Read more about EJB in BEA WebLogicServer Enterprise Java Beans.