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# Package examples.ejb.basic.beanManaged

## Enterprise JavaBean bean-managed persistence
example package and classes

- Client applications
    Client (client application documentation and source)
    Servlet (servlet documentation and source)

- Deployment
    ejb-jar.xml
    weblogic-ejb-jar.xml

- Interfaces
    Account (remote interface documentation and source)
    AccountHome (home interface documentation and source)
    ProcessingErrorException (application-specific exception documentation and source)

- Server (EJBean)
    AccountBean (EJBean documentation and source)

# about this example

This example is a package that demonstrates an Enterprise JavaBean. Please run this example before attempting to create your own Enterprise JavaBeans, as it will show you the different steps involved. The example is an entity EJBean called AccountBean.

The example demonstrates:

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

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

# how to use this example

To get the most out of this example, first read through the source code files. Start with the XML deployment files to find the general structure of the EJBean, which classes are used for the different objects and interfaces, then look at Client.java to see how the application 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 completley invisible to the client; the actual storage is handled by the EJBean directly and not the container.

This example is shipped "pre-built"; you can either run it as shipped, or build the example and run it to test that you are able to successfully build and run EJBeans.

These three sections cover what to do:

1. Build the example
2. Set your environment
3. Run the example

## Build the example

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

We provide separate build scripts for Windows NT and UNIX:

- build.cmd for Windows NT

- build.sh for UNIX

These scripts build the example and place the files in the correct locations:

- Client files: in /myserver/clientclasses
- Servlet: in /myserver/servletclasses
- EJBean: in /myserver/ejb_basic_beanManaged.jar

## Set your environment

1. Set the database persistence

   With database persistence, each instance of an EJBean is written to a row in a table. The table (ejbAccounts) must be created and exist in the database before the example is run. If you are using the evaluation copy of Cloudscape that is included with WebLogic, this table has already been created in the "demo" database.

   You'll need to:

   1. If you're using a database other than Cloudscape, you'll need to create the table in your database using an appropriate SQL statement such as

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

   2. Uncomment the following line from weblogic.properties:

          # Add a TXDataSource for the connection pool:
          weblogic.jdbc.TXDataSource.weblogic.jdbc.jts.demoPool=demoPool

   3. For all databases, setup a connection pool in the weblogic.properties file. For your convenience, a template is included in the file; search for "weblogic.jdbc.connectionPool.demoPool", and uncomment and edit the appropriate lines:

            # You can use this connection pool with any of the EJBean examples.
            # Uncomment to use:
            weblogic.jdbc.connectionPool.demoPool=\
                   url=jdbc:cloudscape:demo,\
                   driver=COM.cloudscape.core.JDBCDriver,\
                   initialCapacity=1,\
                   maxCapacity=2,\
                   capacityIncrement=1,\
                   props=user=none;password=none;server=none

      You can use this pool for Cloudscape. For other databases, you'll need to set an appropriate url and driver, such as

          	  url=jdbc:weblogic:oracle,\
          	  driver=weblogic.jdbc.oci.Driver,\

   4. You'll need to add an access control list (ACL) for users of the pool:

            # Add an ACL for the connection pool:
            weblogic.allow.reserve.weblogic.jdbc.connectionPool.demoPool=everyone

      If you need more information about how to use connection pools, read Using WebLogic JDBC: Using connection pools.

2. Deploy the EJBean by adding the path to the .jar file to the "weblogic.ejb.deploy" property.

   We provide a commented-out version in the property that begins with "weblogic.ejb.deploy" that you can use. You'll need to adjust the property depending on which EJBeans you're building and are deploying, or if the location of the files differs from the installed location.

   Note: If you're running under the Microsoft SDK for Java, you'll also need to add the path to the .jar to the CLASSPATH for your WebLogic Server.

## Run the example

1. Start the WebLogic Server.

   If you're starting the Server from the command line, you'll need to add an entry such as c:/weblogic/eval/cloudscape/lib/cloudscape.jar to the Java system classpath before starting the server, as described in the Administrators Guide Setting up and starting the WebLogic Server.

   You can check that the EJBean has been deployed correctly either by checking the server command line window, or by opening the Console and examining "EJB" under the "Distributed objects"; you should see beanManaged.AccountHome deployed, and can monitor its activity.

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

       $ java examples.ejb.basic.beanManaged.Client

   If you're not running the WebLogic Server with its default settings, you will have to run the client using:

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

   where:

   WebLogicURL
     Domain address of the WebLogic Server
   Port
     Port that is listening for connections (weblogic.system.ListenPort)

   Parameters are optional, but if any are supplied, they are interpreted in this order:

     Parameters:
       url - URL such as "t3://localhost:7001" of Server
       user - User name, default null
       password - User password, default null

3. 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: 0
       Trying to find account with id: ID: 1
       Trying to find account with id: ID: 2
       Trying to find account with id: ID: 3
       Trying to find account with id: ID: 4
       Trying to find account with id: ID: 5
       Trying to find account with id: ID: 6
       Trying to find account with id: ID: 7
       Trying to find account with id: ID: 8
       Trying to find account with id: ID: 9
       Trying to find account with id: ID: 10
       Trying to find account with id: ID: 11
       Trying to find account with id: ID: 12
       Trying to find account with id: ID: 13
       Trying to find account with id: ID: 14
       Trying to find account with id: ID: 15
       Trying to find account with id: ID: 16
       Trying to find account with id: ID: 17
       Trying to find account with id: ID: 18
       Trying to find account with id: ID: 19
       Account: :ID: 0 has a balance of 0.0
       Account: :ID: 1 has a balance of 1000.0
       Account: :ID: 2 has a balance of 2000.0
       Account: :ID: 3 has a balance of 3000.0
       Account: :ID: 4 has a balance of 4000.0
       Account: :ID: 5 has a balance of 5000.0
       Account: :ID: 6 has a balance of 6000.0
       Account: :ID: 7 has a balance of 7000.0
       Account: :ID: 8 has a balance of 8000.0
       Account: :ID: 9 has a balance of 9000.0
       Account: :ID: 10 has a balance of 10000.0
       Account: :ID: 11 has a balance of 11000.0
       Account: :ID: 12 has a balance of 12000.0
       Account: :ID: 13 has a balance of 13000.0
       Account: :ID: 14 has a balance of 14000.0
       Account: :ID: 15 has a balance of 15000.0
       Account: :ID: 16 has a balance of 16000.0
       Account: :ID: 17 has a balance of 17000.0
       Account: :ID: 18 has a balance of 18000.0
       Account: :ID: 19 has a balance of 19000.0

       Querying for accounts with a balance greater than 5000.0...
       Account ID: 6; balance is $6000.0
       Account ID: 7; balance is $7000.0
       Account ID: 8; balance is $8000.0
       Account ID: 9; balance is $9000.0
       Account ID: 10; balance is $10000.0
       Account ID: 11; balance is $11000.0
       Account ID: 12; balance is $12000.0
       Account ID: 13; balance is $13000.0
       Account ID: 14; balance is $14000.0
       Account ID: 15; balance is $15000.0
       Account ID: 16; balance is $16000.0
       Account ID: 17; balance is $17000.0
       Account ID: 18; balance is $18000.0
       Account ID: 19; balance is $19000.0
       Removing beans...

       End beanManaged.Client...

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

       Using user user1 and password user1Password

       Looking up account 10020...
       Did not find 10020
       Account 10020 being created; opening balance is $3000.0

       Part A: Depositing $100.0
       Current balance is $3100.0

       Withdrawing amount greater than current balance. Expecting an
       exception...
       Received expected Processing Error:
       examples.ejb.basic.beanManaged.ProcessingErrorException: Request to
       withdraw $3110.0 more than balance 3100.0 in account 10020

       Part B: Creating 5 new accounts...
       Created account: 9543031558300; balance is $0.0
       Created account: 9543031558301; balance is $100.0
       Created account: 9543031558302; balance is $200.0
       Created account: 9543031558303; balance is $300.0
       Created account: 9543031558304; balance is $400.0

       5 accounts successfully created

       Querying for accounts with a balance greater than 200.0...
       Account 10020; balance is $3100.0
       Account 9543031558303; balance is $300.0
       Account 9543031558304; balance is $400.0

       Removing accounts just created...
       Removed account: 9543031558300
       Removed account: 9543031558301
       Removed account: 9543031558302
       Removed account: 9543031558303
       Removed account: 9543031558304

       End beanManaged.Servlet...

# there's more

Read more about EJB in BEA WebLogic Server Enterprise Java Beans.

Copyright © 1998-2000 BEA Systems, Inc. All rights reserved.

Last updated 03/28/2000