listelresolver.html

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 always throw <code>PropertyNotWritableException</code>.</p>

 <p>If a <code>List</code> was created using 
 <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/util/Collections.html#unmodifiableList(java.util.List)" title="class or interface in java.util"><CODE>Collections.unmodifiableList(java.util.List<? extends T>)</CODE></A>, this method must
 throw <code>PropertyNotWritableException</code>. Unfortunately, 
 there is no Collections API method to detect this. However, an 
 implementation can create a prototype unmodifiable <code>List</code>
 and query its runtime type to see if it matches the runtime type of 
 the base object as a workaround.</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 list to be modified. Only bases of type 
     <code>List</code> are handled by this resolver.<DD><CODE>property</CODE> - The index of the value to be set. Will be coerced
     into an integer.<DD><CODE>val</CODE> - The value to be set at the given index.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/ClassCastException.html" title="class or interface in java.lang">ClassCastException</A></CODE> - if the class of the specified element 
     prevents it from being added to this list.
<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>, or
     if the value is <code>null</code> and this <code>List</code>
     does not support <code>null</code> elements.
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/IllegalArgumentException.html" title="class or interface in java.lang">IllegalArgumentException</A></CODE> - if the property could not be coerced
     into an integer, or if some aspect of the specified element 
     prevents it from being added to this list.
<DD><CODE><A HREF="../../javax/el/PropertyNotWritableException.html" title="class in javax.el">PropertyNotWritableException</A></CODE> - if this resolver was constructed
     in read-only mode, or if the set operation is not supported by 
     the underlying list.
<DD><CODE><A HREF="../../javax/el/PropertyNotFoundException.html" title="class in javax.el">PropertyNotFoundException</A></CODE> - if the given index is out of 
     bounds for this list.
<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="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>If the base object is a list, returns whether a call to 
 <A HREF="../../javax/el/ListELResolver.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.

 <p>If the base is a <code>List</code>, the <code>propertyResolved</code>
 property of the <code>ELContext</code> object must be set to
 <code>true</code> by this 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>If this resolver was constructed in read-only mode, this method will
 always return <code>true</code>.</p>

 <p>If a <code>List</code> was created using 
 <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/util/Collections.html#unmodifiableList(java.util.List)" title="class or interface in java.util"><CODE>Collections.unmodifiableList(java.util.List<? extends T>)</CODE></A>, this method must
 return <code>true</code>. Unfortunately, there is no Collections API
 method to detect this. However, an implementation can create a
 prototype unmodifiable <code>List</code> and query its runtime type
 to see if it matches the runtime type of the base object as a 
 workaround.</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 list to analyze. Only bases of type <code>List</code>
     are handled by this resolver.<DD><CODE>property</CODE> - The index of the element in the list to return the 
     acceptable type for. Will be coerced into an integer, but 
     otherwise ignored by this resolver.
<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 calling the <code>setValue</code> method
     will always fail or <code>false</code> if it is possible that
     such a call may succeed; otherwise undefined.
<DT><B>Throws:</B>
<DD><CODE><A HREF="../../javax/el/PropertyNotFoundException.html" title="class in javax.el">PropertyNotFoundException</A></CODE> - if the given index is out of 
     bounds for this list.
<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/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>Always returns <code>null</code>, since there is no reason to 
 iterate through set set of all integers.

 <p>The <A HREF="../../javax/el/ListELResolver.html#getCommonPropertyType(javax.el.ELContext, java.lang.Object)"><CODE>getCommonPropertyType(javax.el.ELContext, java.lang.Object)</CODE></A> method returns sufficient
 information about what properties this resolver accepts.</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 list. Only bases of type <code>List</code> are 
     handled by this resolver.
<DT><B>Returns:</B><DD><code>null</code>.<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>If the base object is a list, returns the most general type that 
 this resolver accepts for the <code>property</code> argument.
 Otherwise, returns <code>null</code>.

 <p>Assuming the base is a <code>List</code>, this method will always
 return <code>Integer.class</code>. This is because <code>List</code>s
 accept integers as their index.</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 list to analyze. Only bases of type <code>List</code>
     are handled by this resolver.
<DT><B>Returns:</B><DD><code>null</code> if base is not a <code>List</code>; otherwise
     <code>Integer.class</code>.</DL>
</DD>
</DL>
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