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<h2 align="center"> &lt;jsp:useBean&gt;</h2>
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Locates or instantiates a Bean with a specific name and scope.
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<h4> JSP Syntax</h4>
<blockquote><pre><code>&lt;jsp:useBean 
</code>		<code>id="</code><em>beanInstanceName</em><code>"</code> 
		<code>scope="</code><strong>page</strong><code>|request|session|application"
</code>	<code>{	class="</code><em>package.class</em><code>" |</code> 
		<code>type="</code><em>package.class</em><code>" |</code> 
		<code>class="</code><em>package.class</em><code>" type="</code><em>package.class</em><code>" |
</code>		<code>beanName="{ </code><em>package.class</em><em> </em><code>|</code><em> </em><code>&lt;%= </code><em>expression</em> <code>%&gt; }" type="</code><em>package.class</em>"  
	}
	{ 	<code>/&gt; |</code>  
		<code>&gt; </code><em>other tags</em><code> &lt;/jsp:useBean&gt;</code>  
<code>	}
</code></pre></blockquote><a name="16474"> </a>
<h4> Examples</h4>
<blockquote><pre>&lt;jsp:useBean id="cart" scope="session" class="session.Carts" /&gt;
&lt;jsp:setProperty name="cart" property="*" /&gt;

&lt;jsp:useBean id="checking" scope="session" class="bank.Checking" &gt;
&lt;jsp:setProperty name="checking" property="balance" value="0.0" /&gt;
&lt;/jsp:useBean&gt;
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<h4> Description</h4>
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The <code>&lt;jsp:useBean&gt;</code> tag attempts to locates a Bean, or if the Bean does not exist, instantiates it from a class or serialized template. To locate or instantiate the Bean, <code>&lt;jsp:useBean&gt;</code> takes the following steps, in this order:
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<li>Attempts to locate a Bean with the scope and name you specify.
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<li>Defines an object reference variable with the name you specify.
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<li>If it finds the Bean, stores a reference to it in the variable. If you specified <code>type</code>, gives the Bean that type.
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<li>If it does not find the Bean, instantiates it from the class you specify, storing a reference to it in the new variable. If the class name represents a serialized template, the Bean is instantiated by <code>java.beans.Beans.instantiate</code>.
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<li>If it has <em>instantiated</em> (rather than located) the Bean, and if it has body tags (between <code>&lt;jsp:useBean&gt;</code> and <code>&lt;/jsp:useBean&gt;</code>), executes the body tags.
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The body of a <code>&lt;jsp:useBean&gt;</code> tag often contains a <code>&lt;jsp:setProperty&gt;</code> tag that defines property values in the object. As described in <a href="syntaxref.fm14.html#9843">Step &#32;5</a>, the body tags are only processed if <code>&lt;jsp:useBean&gt;</code> instantiates the Bean. If the Bean already exists and <code>&lt;jsp:useBean&gt;</code> locates it, the body tags have no effect.
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In JSP 1.0, <code>&lt;jsp:useBean&gt;</code> works with JavaBeans components, but not with enterprise beans. If you want to use enterprise beans, you can write a JSP file that constructs a JavaBean component, and have the JavaBean component call the enterprise bean.
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<h4> Attributes and Usage</h4>
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<li><code>id="</code><em>beanInstanceName</em><code>"</code>
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Names a variable that identifies the Bean in the scope you specify. You can use the variable name in expressions or scriptlets in the same JSP file. 
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The name is case sensitive and must conform to the naming conventions of the page scripting language (if you use the Java programming language, the conventions in the <em>Java Language Specification</em>). If the Bean has already been created by another <code>&lt;jsp:useBean&gt;</code> tag, the value of <code>id</code> must match the value of <code>id</code> used in the original <code>&lt;jsp:useBean&gt;</code> tag. 
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<li><code>scope="</code><strong>page</strong><code>|request|session|application"</code>
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Defines a scope in which the Bean exists and the variable named in <code>id</code> is available. The default value is <code>page</code>.
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<li><code>class="</code><em>package.class</em><code>"</code>
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Instantiates a Bean from a class, using the <code>new</code> keyword and the class constructor. The class must not be abstract and must have a public, no-argument constructor. The package and class name are case sensitive.
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<li><code>class="</code><em>package.class</em><code>" type="</code><em>package.class</em><code>"</code>
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Instantiates a Bean from a class, using the <code>new</code> keyword and the class constructor, and gives the Bean the type you specify in <code>type</code>. The class you specify in <code>class</code> must not be abstract and must have a public, no-argument constructor. The package and class names you use with both <code>class</code> and <code>type</code> are case sensitive.
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The value of <code>type</code> can be the same as <code>class</code>, a superclass of <code>class</code>, or an interface implemented by <code>class</code>. 
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<li><code>beanName="{ </code><em>package.class</em><code> | &lt;%= </code><em>expression</em><code> %&gt; }" type="</code><em>package.class</em><code>"</code>
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Instantiates a Bean from either a class or a serialized template, using the <code>java.beans.Beans.instantiate</code> method, and gives the Bean the type specified in <code>type</code>. <code>Beans.instantiate</code> checks whether a name represents a class or a serialized template. If the Bean is a serialized template, <code>Beans.instantiate</code> reads the serialized form (with a name like <em>package.class.ser</em>) using a class loader. For more information, see the <em>JavaBeans API Specification</em>.
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The value of <code>beanName</code> is either a package and class name or an <a href="syntaxref.fm4.html#11258">Expression</a> that evaluates to a package and class name, and is passed to <code>Beans.instantiate</code>. The value of <code>type</code> is a package and class name. The value of <code>type</code> can be the same as <code>beanName</code>, a superclass of <code>beanName</code>, or an interface implemented by <code>beanName</code>.
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With both <code>beanName</code> and <code>type</code>, the package and class names are case sensitive.
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<li><code>type="</code><em>package.class</em><code>"</code>
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If the Bean already exists in the specified scope, gives the Bean the type you specify. If you use <code>type</code> without <code>class</code> or <code>beanName</code>, no Bean is instantiated. The package and class name are case sensitive.
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<h4> See Also</h4>
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<li><code><a href="syntaxref.fm13.html#8856">&lt;jsp:setProperty&gt;</a></code>
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<li><code><a href="syntaxref.fm10.html#8820">&lt;jsp:getProperty&gt;</a></code>
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<li>Javadoc API reference for <code>java.beans.Beans</code>
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<li><em>JavaBeans API Specification</em>
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