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       the provided <code>context</code>, <code>base</code>, 
       <code>property</code> and <code>value</code>.</li>
   <li>If the <code>ELContext</code>'s <code>propertyResolved</code>
       flag is <code>false</code> then iteration continues.</li>
   <li>Otherwise, iteration stops and no more component resolvers are
       considered.</li>
 </ol></p>

 <p>If none of the component resolvers were able to perform this
 operation, the <code>propertyResolved</code> flag remains set to 
 <code>false</code></p>.

 <p>Any exception thrown by component resolvers during the iteration
 is propagated to the caller of this method.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)">setValue</A></CODE> in class <CODE><A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The context of this evaluation.<DD><CODE>base</CODE> - The base object whose property value is to be set,
     or <code>null</code> to set a top-level variable.<DD><CODE>property</CODE> - The property or variable to be set.<DD><CODE>val</CODE> - The value to set the property or variable to.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/NullPointerException.html" title="class or interface in java.lang">NullPointerException</A></CODE> - if context is <code>null</code>
<DD><CODE><A HREF="../../javax/el/PropertyNotFoundException.html" title="class in javax.el">PropertyNotFoundException</A></CODE> - if the given (base, property) pair
     is handled by this <code>ELResolver</code> but the specified
     variable or property does not exist.
<DD><CODE><A HREF="../../javax/el/PropertyNotWritableException.html" title="class in javax.el">PropertyNotWritableException</A></CODE> - if the given (base, property)
     pair is handled by this <code>ELResolver</code> but the specified
     variable or property is not writable.
<DD><CODE><A HREF="../../javax/el/ELException.html" title="class in javax.el">ELException</A></CODE> - if an exception was thrown while attempting to
     set the property or variable. The thrown exception
     must be included as the cause property of this exception, if
     available.</DL>
</DD>
</DL>
<HR>

<A NAME="isReadOnly(javax.el.ELContext, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
isReadOnly</H3>
<PRE>
public boolean <B>isReadOnly</B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
                          <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base,
                          <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;property)</PRE>
<DL>
<DD>For a given <code>base</code> and <code>property</code>, attempts to
 determine whether a call to <A HREF="../../javax/el/CompositeELResolver.html#setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)"><CODE>setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)</CODE></A> will always fail. The
 result is obtained by querying all component resolvers.

 <p>If this resolver handles the given (base, property) pair, 
 the <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code>
 by the resolver, before returning. If this property is not 
 <code>true</code> after this method is called, the caller should ignore 
 the return value.</p>

 <p>First, <code>propertyResolved</code> is set to <code>false</code> on
 the provided <code>ELContext</code>.</p>

 <p>Next, for each component resolver in this composite:
 <ol>
   <li>The <code>isReadOnly()</code> method is called, passing in
       the provided <code>context</code>, <code>base</code> and 
       <code>property</code>.</li>
   <li>If the <code>ELContext</code>'s <code>propertyResolved</code>
       flag is <code>false</code> then iteration continues.</li>
   <li>Otherwise, iteration stops and no more component resolvers are
       considered. The value returned by <code>isReadOnly()</code> is
       returned by this method.</li>
 </ol></p>

 <p>If none of the component resolvers were able to perform this
 operation, the value <code>false</code> is returned and the
 <code>propertyResolved</code> flag remains set to 
 <code>false</code></p>.

 <p>Any exception thrown by component resolvers during the iteration
 is propagated to the caller of this method.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#isReadOnly(javax.el.ELContext, java.lang.Object, java.lang.Object)">isReadOnly</A></CODE> in class <CODE><A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The context of this evaluation.<DD><CODE>base</CODE> - The base object whose property value is to be analyzed,
     or <code>null</code> to analyze a top-level variable.<DD><CODE>property</CODE> - The property or variable to return the read-only status
     for.
<DT><B>Returns:</B><DD>If the <code>propertyResolved</code> property of 
     <code>ELContext</code> was set to <code>true</code>, then
     <code>true</code> if the property is read-only or
     <code>false</code> if not; otherwise undefined.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/NullPointerException.html" title="class or interface in java.lang">NullPointerException</A></CODE> - if context is <code>null</code>
<DD><CODE><A HREF="../../javax/el/PropertyNotFoundException.html" title="class in javax.el">PropertyNotFoundException</A></CODE> - if the given (base, property) pair
     is handled by this <code>ELResolver</code> but the specified
     variable or property does not exist.
<DD><CODE><A HREF="../../javax/el/ELException.html" title="class in javax.el">ELException</A></CODE> - if an exception was thrown while performing
     the property or variable resolution. The thrown exception
     must be included as the cause property of this exception, if
     available.</DL>
</DD>
</DL>
<HR>

<A NAME="getFeatureDescriptors(javax.el.ELContext, java.lang.Object)"><!-- --></A><H3>
getFeatureDescriptors</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/util/Iterator.html" title="class or interface in java.util">Iterator</A>&lt;<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/beans/FeatureDescriptor.html" title="class or interface in java.beans">FeatureDescriptor</A>&gt; <B>getFeatureDescriptors</B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
                                                         <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base)</PRE>
<DL>
<DD>Returns information about the set of variables or properties that 
 can be resolved for the given <code>base</code> object. One use for
 this method is to assist tools in auto-completion. The results are
 collected from all component resolvers.

 <p>The <code>propertyResolved</code> property of the 
 <code>ELContext</code> is not relevant to this method.
 The results of all <code>ELResolver</code>s are concatenated.</p>

 <p>The <code>Iterator</code> returned is an iterator over the
 collection of <code>FeatureDescriptor</code> objects returned by
 the iterators returned by each component resolver's 
 <code>getFeatureDescriptors</code> method. If <code>null</code> is 
 returned by a resolver, it is skipped.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#getFeatureDescriptors(javax.el.ELContext, java.lang.Object)">getFeatureDescriptors</A></CODE> in class <CODE><A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The context of this evaluation.<DD><CODE>base</CODE> - The base object whose set of valid properties is to
     be enumerated, or <code>null</code> to enumerate the set of
     top-level variables that this resolver can evaluate.
<DT><B>Returns:</B><DD>An <code>Iterator</code> containing zero or more (possibly
     infinitely more) <code>FeatureDescriptor</code> objects, or 
     <code>null</code> if this resolver does not handle the given 
     <code>base</code> object or that the results are too complex to 
     represent with this method<DT><B>See Also:</B><DD><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/beans/FeatureDescriptor.html" title="class or interface in java.beans"><CODE>FeatureDescriptor</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="getCommonPropertyType(javax.el.ELContext, java.lang.Object)"><!-- --></A><H3>
getCommonPropertyType</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Class.html" title="class or interface in java.lang">Class</A>&lt;?&gt; <B>getCommonPropertyType</B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
                                      <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base)</PRE>
<DL>
<DD>Returns the most general type that this resolver accepts for the
 <code>property</code> argument, given a <code>base</code> object.
 One use for this method is to assist tools in auto-completion. The
 result is obtained by querying all component resolvers.

 <p>The <code>Class</code> returned is the most specific class that is
 a common superclass of all the classes returned by each component
 resolver's <code>getCommonPropertyType</code> method. If 
 <code>null</code> is returned by a resolver, it is skipped.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#getCommonPropertyType(javax.el.ELContext, java.lang.Object)">getCommonPropertyType</A></CODE> in class <CODE><A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The context of this evaluation.<DD><CODE>base</CODE> - The base object to return the most general property
     type for, or <code>null</code> to enumerate the set of
     top-level variables that this resolver can evaluate.
<DT><B>Returns:</B><DD><code>null</code> if this <code>ELResolver</code> does not
     know how to handle the given <code>base</code> object; otherwise
     <code>Object.class</code> if any type of <code>property</code>
     is accepted; otherwise the most general <code>property</code>
     type accepted for the given <code>base</code>.</DL>
</DD>
</DL>
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