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<a name="wp85894"> </a><p class="pBody">
For example, suppose you define a welcome file <code class="cCode">welcome.html</code>. When a client requests a URL such as <code class="cVariable">host:port/webapp/directory</code>, where <code class="cVariable">directory</code> is not mapped to a servlet or JSP page, the file <code class="cVariable">host:port/webapp/directory</code><code class="cCode">/welcome.html </code>is returned to the client. 
</p>
<a name="wp85895"> </a><p class="pBody">
If a Web container receives a valid partial request, the Web container examines the welcome file list and appends each welcome file in the order specified to the partial request and checks whether a static resource or servlet in the WAR is mapped to that request URL. The Web container then sends the request to the first resource in the WAR that matches. 
</p>
<a name="wp88445"> </a><p class="pBody">
If no welcome file is specified, the J2EE 1.4 Application Server will use a file named <code class="cCode">index.</code><code class="cVariable">XXX</code>, where <code class="cVariable">XXX</code> can be <code class="cCode">html</code> or <code class="cCode">jsp</code>, as the default welcome file. If there is no welcome file and no file named <code class="cCode">index.</code><code class="cVariable">XXX</code>, the application server returns a directory listing.
</p>
<a name="wp215022"> </a><p class="pBody">
To specify welcome files with <code class="cCode">deploytool</code>:
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp215023"> </a><div class="pSmartList1"><li>Select the WAR.</li></div>
<a name="wp215024"> </a><div class="pSmartList1"><li>Select the File Refs tab in the WAR inspector. </li></div>
<a name="wp215025"> </a><div class="pSmartList1"><li>Click Add File in the Welcome Files pane.</li></div>
<a name="wp215026"> </a><div class="pSmartList1"><li>Select the welcome file from the drop-down list.</li></div>
</ol></div>
<a name="wp188453"> </a><p class="pBody">
The example discussed in <a  href="JSPTags5.html#wp89664">Encapsulating Reusable Content using Tag Files</a> has a welcome file.
</p>
<a name="wp99549"> </a><h3 class="pHeading2">
Setting Initialization Parameters
</h3>
<a name="wp215045"> </a><p class="pBody">
The Web components in a Web module share an object that represents their application context (see <a  href="Servlets10.html#wp64724">Accessing the Web Context</a>). You can pass initialization parameters to the context or to a Web component. To add a Web component initialization parameter with <code class="cCode">deploytool</code>:
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp215046"> </a><div class="pSmartList1"><li>Select the Web component.</li></div>
<a name="wp215047"> </a><div class="pSmartList1"><li>Select the Init. Parameters tab in the Web component inspector. </li></div>
<a name="wp215048"> </a><div class="pSmartList1"><li>Click Add.</li></div>
</ol></div>
<a name="wp215053"> </a><p class="pBody">
To add a context parameter with <code class="cCode">deploytool</code>:
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp215054"> </a><div class="pSmartList1"><li>Select the WAR.</li></div>
<a name="wp215055"> </a><div class="pSmartList1"><li>Select the Context tab in the WAR inspector. </li></div>
<a name="wp215056"> </a><div class="pSmartList1"><li>Click Add.</li></div>
</ol></div>
<a name="wp102465"> </a><p class="pBody">
For an example context parameter, see the example discussed in <a  href="JSPIntro3.html#wp83415">The Example JSP Pages</a>.
</p>
<a name="wp83548"> </a><h3 class="pHeading2">
Specifying Error Mappings
</h3>
<a name="wp215078"> </a><p class="pBody">
You can specify a mapping between the status code returned in an HTTP response or a Java programming language exception returned by any Web component and a Web resource (see <a  href="Servlets4.html#wp76701">Handling Errors</a>). To set up the mapping with <code class="cCode">deploytool</code>:
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp215079"> </a><div class="pSmartList1"><li>Select the WAR.</li></div>
<a name="wp215080"> </a><div class="pSmartList1"><li>Select the File Refs tab in the WAR inspector. </li></div>
<a name="wp215081"> </a><div class="pSmartList1"><li>Click Add Error in the Error Mapping pane.</li></div>
<a name="wp215085"> </a><div class="pSmartList1"><li>Enter the HTTP status code (see <a  href="HTTP3.html#wp63687">HTTP Responses</a>) or fully-qualified class name of an exception in the Error/Exception field.</li></div>
<a name="wp215086"> </a><div class="pSmartList1"><li>Enter the name of a resource to be invoked when the status code or exception is returned. The name should have a leading forward slash <code class="cCode">/</code>.</li></div>
</ol></div>
<hr>
<a name="wp84126"> </a><p class="pNote">
Note: You can also define error pages for a JSP page contained in a WAR. If error pages are defined for both the WAR and a JSP page, the JSP page's error page takes precedence. See <a  href="JSPIntro4.html#wp65997">Handling Errors&nbsp;</a>.
</p>
<hr><a name="wp81804"> </a><p class="pBody">
For an example error page mapping, see the example discussed in <a  href="Servlets3.html#wp63984">The Example Servlets</a>.
</p>
<a name="wp83876"> </a><h3 class="pHeading2">
Declaring References to Environment Entries, Resource Environment Entries, or Resources
</h3>
<a name="wp215121"> </a><p class="pBody">
If your Web components reference environment entries, resource environment entries, or resources such as databases, you must declare the references in the Web application deployment descriptor. To add a reference to a resource with <code class="cCode">deploytool</code>:
</p>
<div class="pSmartList1"><ol type="1" class="pSmartList1">
<a name="wp215122"> </a><div class="pSmartList1"><li>Select the WAR.</li></div>
<a name="wp215123"> </a><div class="pSmartList1"><li>Select the Environment, Enterprise Bean Refs, Resource Env. Refs, or Resource Refs tab in the WAR inspector. </li></div>
<a name="wp215124"> </a><div class="pSmartList1"><li>Click Add to add a new reference.</li></div>
<a name="wp215125"> </a><div class="pSmartList1"><li>Type a JNDI name for the resource.</li></div>
<a name="wp215126"> </a><div class="pSmartList1"><li>Choose the type of the resource.</li></div>
<a name="wp215127"> </a><div class="pSmartList1"><li>Choose whether the container or the application performs authentication when the resource is accessed.</li></div>
<a name="wp215128"> </a><div class="pSmartList1"><li>Choose whether the resource can be shared by more than one Web application.</li></div>
</ol></div>
<a name="wp81797"> </a><p class="pBody">
For an example resource reference, see <a  href="WebApp13.html#wp85541">Configuring the Web Application to Reference a Resource</a>.
</p>
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