mapelresolver.html

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<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../javax/el/MapELResolver.html#getValue(javax.el.ELContext, java.lang.Object, java.lang.Object)">getValue</A></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)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If the base object is a map, returns the value associated with the
 given key, as specified by the <code>property</code> argument.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../javax/el/MapELResolver.html#isReadOnly(javax.el.ELContext, java.lang.Object, java.lang.Object)">isReadOnly</A></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)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If the base object is a map, returns whether a call to 
 <A HREF="../../javax/el/MapELResolver.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.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../javax/el/MapELResolver.html#setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)">setValue</A></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,
         <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;val)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If the base object is a map, attempts to set the value associated with
 the given key, as specified by the <code>property</code> argument.</TD>
</TR>
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&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
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<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
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<!-- ========= CONSTRUCTOR DETAIL ======== -->

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<B>Constructor Detail</B></FONT></TH>
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<A NAME="MapELResolver()"><!-- --></A><H3>
MapELResolver</H3>
<PRE>
public <B>MapELResolver</B>()</PRE>
<DL>
<DD>Creates a new read/write <code>MapELResolver</code>.
<P>
</DL>
<HR>

<A NAME="MapELResolver(boolean)"><!-- --></A><H3>
MapELResolver</H3>
<PRE>
public <B>MapELResolver</B>(boolean&nbsp;isReadOnly)</PRE>
<DL>
<DD>Creates a new <code>MapELResolver</code> whose read-only status is
 determined by the given parameter.
<P>
<DL>
<DT><B>Parameters:</B><DD><CODE>isReadOnly</CODE> - <code>true</code> if this resolver cannot modify
     maps; <code>false</code> otherwise.</DL>
</DL>

<!-- ============ METHOD DETAIL ========== -->

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<B>Method Detail</B></FONT></TH>
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<A NAME="getType(javax.el.ELContext, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
getType</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>getType</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 map, returns the most general acceptable type 
 for a value in this map.

 <p>If the base is a <code>Map</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>Assuming the base is a <code>Map</code>, this method will always
 return <code>Object.class</code>. This is because <code>Map</code>s
 accept any object as the value for a given key.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#getType(javax.el.ELContext, java.lang.Object, java.lang.Object)">getType</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 map to analyze. Only bases of type <code>Map</code>
     are handled by this resolver.<DD><CODE>property</CODE> - The key to return the acceptable type for.
     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
     the most general acceptable type; 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/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="getValue(javax.el.ELContext, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
getValue</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A> <B>getValue</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 map, returns the value associated with the
 given key, as specified by the <code>property</code> argument. If the
 key was not found, <code>null</code> is returned.

 <p>If the base is a <code>Map</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>Just as in <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/util/Map.html#get(java.lang.Object)" title="class or interface in java.util"><CODE>Map.get(java.lang.Object)</CODE></A>, just because <code>null</code>
 is returned doesn't mean there is no mapping for the key; it's also
 possible that the <code>Map</code> explicitly maps the key to
 <code>null</code>.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#getValue(javax.el.ELContext, java.lang.Object, java.lang.Object)">getValue</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 map to be analyzed. Only bases of type <code>Map</code>
     are handled by this resolver.<DD><CODE>property</CODE> - The key whose associated value is to be returned.
<DT><B>Returns:</B><DD>If the <code>propertyResolved</code> property of 
     <code>ELContext</code> was set to <code>true</code>, then
     the value associated with the given key or <code>null</code>
     if the key was not found. Otherwise, undefined.
<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 key is of an inappropriate type 
     for this map (optionally thrown by the underlying <code>Map</code>).
<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 key is null and this map does not permit null keys (the
     latter is optionally thrown by the underlying <code>Map</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="setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
setValue</H3>
<PRE>
public void <B>setValue</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,
                     <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;val)</PRE>
<DL>
<DD>If the base object is a map, attempts to set the value associated with
 the given key, as specified by the <code>property</code> argument.

 <p>If the base is a <code>Map</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 
 can safely assume no value was set.</p>

 <p>If this resolver was constructed in read-only mode, this method will
 always throw <code>PropertyNotWritableException</code>.</p>

 <p>If a <code>Map</code> was created using 
 <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/util/Collections.html#unmodifiableMap(java.util.Map)" title="class or interface in java.util"><CODE>Collections.unmodifiableMap(java.util.Map<? extends K, ? extends V>)</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>Map</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>