scopedattributeelresolver.html

j2ee帮助文档软件设计/软件工程 文件格式

<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/Class.html" title="class or interface in java.lang">Class</A>&lt;<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&gt;</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../../javax/servlet/jsp/el/ScopedAttributeELResolver.html#getType(javax.el.ELContext, java.lang.Object, java.lang.Object)">getType</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 <code>null</code>, returns 
 <code>Object.class</code> to indicate that any type is valid to
 set for a scoped attribute.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<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/servlet/jsp/el/ScopedAttributeELResolver.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 <code>null</code>, searches the page, 
 request, session and application scopes for an attribute with
 the given name and returns it, or <code>null</code> if no
 attribute exists with the current name.</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/servlet/jsp/el/ScopedAttributeELResolver.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 <code>null</code>, returns <code>false</code>
 to indicate that scoped attributes are never read-only.</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/servlet/jsp/el/ScopedAttributeELResolver.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 <code>null</code>, sets an existing scoped
 attribute to the new value, or creates a new scoped attribute if one
 does not exist by this name.</TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<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>
</TR>
</TABLE>
&nbsp;
<P>

<!-- ========= CONSTRUCTOR DETAIL ======== -->

<A NAME="constructor_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2">
<B>Constructor Detail</B></FONT></TH>
</TR>
</TABLE>

<A NAME="ScopedAttributeELResolver()"><!-- --></A><H3>
ScopedAttributeELResolver</H3>
<PRE>
public <B>ScopedAttributeELResolver</B>()</PRE>
<DL>
</DL>

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

<A NAME="method_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2">
<B>Method Detail</B></FONT></TH>
</TR>
</TABLE>

<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 <code>null</code>, searches the page, 
 request, session and application scopes for an attribute with
 the given name and returns it, or <code>null</code> if no
 attribute exists with the current name.

 <p>The <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code> by 
 this resolver before returning if base is <code>null</code>. If 
 this property is not <code>true</code> after this method is called,
 the caller should ignore the return value.</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> - Only <code>null</code> is handled by this resolver.
     Other values will result in an immediate return.<DD><CODE>property</CODE> - The name of the scoped attribute to resolve.
<DT><B>Returns:</B><DD>If the <code>propertyResolved</code> property of 
     <code>ELContext</code> was set to <code>true</code>, then
     the scoped attribute; 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/servlet/jsp/el/ELException.html" title="class in javax.servlet.jsp.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="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;<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&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 <code>null</code>, returns 
 <code>Object.class</code> to indicate that any type is valid to
 set for a scoped attribute.

 <p>The <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code> by 
 this resolver before returning if base is <code>null</code>. If 
 this property is not <code>true</code> after this method is called,
 the caller should ignore the return value.</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> - Only <code>null</code> is handled by this resolver.
     Other values will result in an immediate return.<DD><CODE>property</CODE> - The name of the scoped attribute to resolve.
<DT><B>Returns:</B><DD>If the <code>propertyResolved</code> property of 
     <code>ELContext</code> was set to <code>true</code>, then
     <code>Object.class</code>; 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/servlet/jsp/el/ELException.html" title="class in javax.servlet.jsp.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 <code>null</code>, sets an existing scoped
 attribute to the new value, or creates a new scoped attribute if one
 does not exist by this name.

 <p>If the provided attribute name matches the key of an attribute 
 in page scope, request scope, session scope, or application scope, the 
 corresponding attribute value will be replaced by the provided value.
 Otherwise, a new page scope attribute will be created with the
 given name and value.</p>

 <p>The <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code> by 
 this resolver before returning if base is <code>null</code>. If 
 this property is not <code>true</code> after this method is called,