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<a name="wp79923"> </a><div class="pSmartList1"><li>It returns the remote interface type of the enterprise bean.</li></div>
<a name="wp79925"> </a><div class="pSmartList1"><li>The <code class="cCode">throws</code> clause includes the exceptions specified by the <code class="cCode">throws</code> clause of the corresponding <code class="cCode">ejbCreate</code> and <code class="cCode">ejbPostCreate</code> methods.</li></div>
<a name="wp79926"> </a><div class="pSmartList1"><li>The <code class="cCode">throws</code> clause includes the <code class="cCode">javax.ejb.CreateException.</code></li></div>
<a name="wp79927"> </a><div class="pSmartList1"><li>If the method is defined in a remote--not local--home interface, then the <code class="cCode">throws</code> clause includes the <code class="cCode">java.rmi.RemoteException</code>.</li></div>
</ul></div>
<a name="wp79928"> </a><h4 class="pHeading3">
Finder Method Definitions
</h4>
<a name="wp79930"> </a><p class="pBody">
Every finder method in the home interface corresponds to a finder method in the entity bean class. The name of a finder method in the home interface begins with <code class="cCode">find</code>, whereas the corresponding name in the entity bean class begins with <code class="cCode">ejbFind</code>. For example, the <code class="cCode">SavingsAccountHome</code> class defines the <code class="cCode">findByLastName</code> method, and the <code class="cCode">SavingsAccountBean</code> class implements the <code class="cCode">ejbFindByLastName</code> method. The rules for defining the signatures of the finder methods of a home interface follow.
</p>
<div class="pSmartList1"><ul class="pSmartList1">
<a name="wp79931"> </a><div class="pSmartList1"><li>The number and types of arguments must match those of the corresponding method in the entity bean class.</li></div>
<a name="wp79932"> </a><div class="pSmartList1"><li>The return type is the entity bean's remote interface type, or a collection of those types.</li></div>
<a name="wp79933"> </a><div class="pSmartList1"><li>The exceptions in the <code class="cCode">throws</code> clause include those of the corresponding method in the entity bean class.</li></div>
<a name="wp79934"> </a><div class="pSmartList1"><li>The <code class="cCode">throws</code> clause contains the <code class="cCode">javax.ejb.FinderException</code>.</li></div>
<a name="wp79935"> </a><div class="pSmartList1"><li>If the method is defined in a remote--not local--home interface, then the throws clause includes the <code class="cCode">java.rmi.RemoteException</code>.</li></div>
</ul></div>
<a name="wp79937"> </a><h4 class="pHeading3">
Home Method Definitions
</h4>
<a name="wp79939"> </a><p class="pBody">
Each home method definition in the home interface corresponds to a method in the entity bean class. In the home interface, the method name is arbitrary, provided that it does not begin with <code class="cCode">create</code> or <code class="cCode">find</code>. In the bean class, the matching method name begins with <code class="cCode">ejbHome</code>. For example, in the <code class="cCode">SavingsAccountBean</code> class the name is <code class="cCode">ejbHomeChargeForLowBalance</code>, but in the <code class="cCode">SavingsAccountHome</code> interface the name is <code class="cCode">chargeForLowBalance</code>.
</p>
<a name="wp79940"> </a><p class="pBody">
The home method signature must follow the same rules specified for finder methods in the previous section (except that a home method does not throw a <code class="cCode">FinderException</code>). 
</p>
<a name="wp79941"> </a><h3 class="pHeading2">
Remote Interface
</h3>
<a name="wp79942"> </a><p class="pBody">
The remote interface extends <code class="cCode">javax.ejb.EJBObject</code> and defines the business methods that a remote client may invoke. Here is the <code class="cCode">SavingsAccount</code> remote interface:
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
import javax.ejb.EJBObject;
import java.rmi.RemoteException;
import java.math.BigDecimal;

public interface SavingsAccount extends EJBObject {
    
    public void debit(BigDecimal amount)
        throws InsufficientBalanceException, RemoteException;

    public void credit(BigDecimal amount)
        throws RemoteException;
 
    public String getFirstName()
        throws RemoteException;

    public String getLastName()
        throws RemoteException;
   
    public BigDecimal getBalance()
        throws RemoteException;
}<a name="wp79944"> </a>
</pre></div>
<a name="wp79945"> </a><p class="pBody">
The requirements for the method definitions in a remote interface are the same for both session and entity beans:
</p>
<div class="pSmartList1"><ul class="pSmartList1">
<a name="wp79946"> </a><div class="pSmartList1"><li>Each method in the remote interface must match a method in the enterprise bean class.</li></div>
<a name="wp79947"> </a><div class="pSmartList1"><li>The signatures of the methods in the remote interface must be identical to the signatures of the corresponding methods in the enterprise bean class.</li></div>
<a name="wp79948"> </a><div class="pSmartList1"><li>The arguments and return values must be valid RMI types. </li></div>
<a name="wp79949"> </a><div class="pSmartList1"><li>The <code class="cCode">throws</code> clause must include <code class="cCode">java.rmi.RemoteException.</code></li></div>
</ul></div>
<a name="wp79951"> </a><p class="pBody">
A local interface has the same requirements, with the following exceptions:
</p>
<div class="pSmartList1"><ul class="pSmartList1">
<a name="wp79952"> </a><div class="pSmartList1"><li>The arguments and return values are not required to be valid RMI types. </li></div>
<a name="wp79953"> </a><div class="pSmartList1"><li>The <code class="cCode">throws</code> clause does not include <code class="cCode">java.rmi.RemoteException.</code></li></div>
</ul></div>
<a name="wp79955"> </a><h3 class="pHeading2">
Running the SavingsAccountEJB Example
</h3>
<a name="wp80612"> </a><p class="pBody">
Before you run this example, you must define the datasource, create the database, and deploy the <code class="cCode">SavingsAccountApp.ear</code> file.
</p>
<a name="wp80803"> </a><h4 class="pHeading3">
Defining the Data Source
</h4>
<a name="wp80959"> </a><p class="pBody">
Follow the instructions in <a  href="Resources4.html#wp81695">Defining a Data Source in the J2EE Application Server</a>. This data source is a factory for database connections. For more information, see <a  href="Resources3.html#wp80235">DataSource Objects and Connection Pools</a>.
</p>
<a name="wp79957"> </a><h4 class="pHeading3">
Creating the Database Table
</h4>
<a name="wp79958"> </a><p class="pBody">
The instructions that follow explain how to use the <code class="cCode">SavingsAccountEJB</code> example with PointBase, the database software that is included in the J2EE Application Server bundle. 
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp80812"> </a><div class="pSmartList1"><li>Start the PointBase server. For instructions, see <a  href="WebApp13.html#wp83431">Starting the PointBase Database Server</a>.</li></div>
<a name="wp80814"> </a><div class="pSmartList1"><li>Create the <code class="cCode">savingsaccount</code> database table by running the <code class="cCode">create.sql</code> script.</li></div>
<div class="pSmartList2"><ol type="a" class="pSmartList2">
<a name="wp80794"> </a><div class="pSmartList2"><li>In a terminal window, go to this directory:</li></div>
<a name="wp80976"> </a><p class="pBodyRelative">
<code class="cCode">&lt;</code><code class="cVariable">INSTALL</code><code class="cCode">&gt;/j2eetutorial14/examples/ejb/savingsaccount/ </code>
</p>
<a name="wp80795"> </a><div class="pSmartList2"><li>Type the following command, which runs the <code class="cCode">create.sql </code>script:</li></div>
<a name="wp81036"> </a><p class="pBodyRelative">
<code class="cCode">asant create-db_common</code>
</p>
</ol></div>
</ol></div>
<a name="wp79968"> </a><h4 class="pHeading3">
Deploying the Application
</h4>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp79969"> </a><div class="pSmartList1"><li>In <code class="cCode">deploytool</code>, open the <code class="cCode">SavingsAccountApp.ear</code> file, which resides in this directory:</li></div>
<a name="wp80981"> </a><p class="pBodyRelative">
<code class="cCode">&lt;</code><code class="cVariable">INSTALL</code><code class="cCode">&gt;/j2eetutorial14/examples/ejb/provided-ears/ </code>
</p>
<a name="wp79970"> </a><div class="pSmartList1"><li>Deploy the <code class="cCode">SavingsAccountApp</code> application. </li></div>
<a name="wp80855"> </a><div class="pSmartList1"><li>In the Deploy Module dialog box, do the following: </li></div>
<div class="pSmartList2"><ol type="a" class="pSmartList2">
<a name="wp80858"> </a><div class="pSmartList2"><li>Select the Return Client JAR checkbox. </li></div>
<a name="wp80862"> </a><div class="pSmartList2"><li>In the field below the check box, enter the following:</li></div>
<a name="wp80886"> </a><p class="pBodyRelative">
<code class="cCode">&lt;</code><code class="cVariable">INSTALL</code><code class="cCode">&gt;/j2eetutorial14/examples/ejb/savingsaccount </code>
</p>
</ol></div>
</ol></div>
<a name="wp80861"> </a><p class="pBody">
For detailed instructions, see <a  href="EJB8.html#wp80064">Deploying the J2EE Application</a>. 
</p>
<a name="wp79975"> </a><h4 class="pHeading3">
Running the Client
</h4>
<a name="wp80918"> </a><p class="pBody">
To run the <code class="cCode">SavingsAccountClient</code> program, do the following:
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp79976"> </a><div class="pSmartList1"><li>In a terminal window, go to this directory: </li></div>
<a name="wp80883"> </a><p class="pBodyRelative">
<code class="cCode">&lt;</code><code class="cVariable">INSTALL</code><code class="cCode">&gt;/j2eetutorial14/examples/ejb/savingsaccount/</code>
</p>
<a name="wp80875"> </a><div class="pSmartList1"><li>Type the following command on a single line:</li></div>
<a name="wp80876"> </a><p class="pBodyRelative">
<code class="cCode">appclient -client SavingsAccountAppClient.jar</code>
</p>
<a name="wp79981"> </a><div class="pSmartList1"><li>The client should display the following lines:</li></div>
<a name="wp81061"> </a><p class="pBodyRelative">
<code class="cCode">balance = 68.25<br />balance = 32.55<br />456: 44.77<br />730: 19.54<br />268: 100.07<br />836: 32.55<br />456: 44.77<br />4<br />7</code>
</p>
</ol></div>
<a name="wp80984"> </a><p class="pBody">
To modify this example, see the instructions in <a  href="EJB11.html#wp81442">Modifying the J2EE Application</a>.
</p>
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