[JCS-207] JCSAdmin.jsp throws ClassCastException java.util.LinkedList cannot be cast to [Lorg.apache.commons.jcs3.admin.CacheRegionInfo

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: jcs-3.0
• Fix Version/s: jcs-3.1
• Component/s: Documentation
• Assignee: Thomas Vandahl
• Reporter: Reval Pal
• Created: 21/Oct/20 05:08
• Updated: 18/Sep/23 17:34
• Resolved: 02/Nov/20 18:23

Description

The sample JCSAdmin.jsp on URL https://raw.githubusercontent.com/apache/commons-jcs/master/commons-jcs-core/src/main/java/org/apache/commons/jcs3/admin/JCSAdmin.jsp as referred to by https://commons.apache.org/proper/commons-jcs/faq.html

Where can I get the admin jsp?
You can download the admin jsp here .

Throws exception when running:

org.apache.jasper.JasperException: JBWEB004038: An exception occurred processing JSP page /JCSAdmin.jsp at line 254

254

251: 		Retrieve (key) <input type="text" name="key"> &nbsp;
252: 		(region) <select name="cacheName">
253: <%
254:   CacheRegionInfo[] listSelect = (CacheRegionInfo[]) context.get( "cacheInfoRecords" );
255:   for (CacheRegionInfo record : listSelect)
256:   {
257: 	%>


Caused by: java.lang.ClassCastException: java.util.LinkedList cannot be cast to [Lorg.apache.commons.jcs3.admin.CacheRegionInfo;
	at org.apache.jsp.JCSAdmin_jsp._jspService(JCSAdmin_jsp.java:389)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:791)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:433)

Solution

3 places to fix:
1)

 line 203 :
<%
	CacheElementInfo[] list = (CacheElementInfo[]) context.get( "elementInfoRecords" );
    for (CacheElementInfo element : list)
    {
%>

should be

<%
    for (CacheElementInfo element : (java.util.List<CacheElementInfo>)context.get( "elementInfoRecords" ))
    {
%>

2)

 line 253
<%
  CacheRegionInfo[] listSelect = (CacheRegionInfo[]) context.get( "cacheInfoRecords" );
  for (CacheRegionInfo record : listSelect)
  {

should be

<%
    for (CacheRegionInfo record : (java.util.List<CacheRegionInfo>)context.get( "cacheInfoRecords" ))
    {

3)

 line 279
<%
	CacheRegionInfo[] list = (CacheRegionInfo[]) context.get( "cacheInfoRecords" );
    for (CacheRegionInfo record : listSelect)
    {
%>

should be

<%
    for (CacheRegionInfo record : (java.util.List<CacheRegionInfo>)context.get( "cacheInfoRecords" ))
    {
%>

Also some styling nitpicking:

 line 229
    <pre>
    	<%=stats%>
    </pre>

should be

<pre>
<%=stats%>
</pre>

(removes the spaces in the rendered page).