Type mismatch: cannot convert from Object to HashMap

Hi

I am trying to pass the ArrayList as a request to result.jsp using requestdispatcher.
I am getting syntax error as below

org.apache.jasper.JasperException: Exception in JSP: /update.jsp:46

43:  RequestDispatcher view =
44:  request.getRequestDispatcher("result.jsp");
45:  //--Use the request dispatche to ask the container to crank JSP
46:  view.forward(request, response);
47: %>
48: </body>
49: </html>


Stacktrace:
      org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:504)
      org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
      org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
      org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
      javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
      org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)

root cause

org.apache.jasper.JasperException: Unable to compile class for JSP

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
Type mismatch: cannot convert from Object to List

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
it cannot be resolved

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
Type mismatch: cannot convert from Object to HashMap

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
length.calval cannot be resolved to a type

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
Type mismatch: cannot convert from Object to int

CODE

result.jsp

<%@ page language="java" import="java.sql.*" import="java.util.*" %>
<html>
<body>
<%
List  a1 = request.getAttribute("data");
Iterator listIt = a1.iterator ();
while (it.hasNext ()) {
    HashMap colval = listIt.next();
    int id;
    for(int i = 1; i <= length.calval; i++) {
    Integer key = new Integer(i);
      String iKey = key.toString();
      if(i == 1){
      id = colval.get(iKey);
      }
      else{
      %>
      <%= colval.get(iKey) %>
<%  
      }
 }
 %>
 <br>
 <%
}
%>
</body>
</html>
basiranaAsked:
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jaggernatConnect With a Mentor Commented:
try this

List  a1 = (List)request.getAttribute("data");
0
 
basiranaAuthor Commented:
Hi

Still I am getting below error can you please check once.

Exception

org.apache.jasper.JasperException: Unable to compile class for JSP

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
Type mismatch: cannot convert from Object to HashMap

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
length.colval cannot be resolved to a type

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
Type mismatch: cannot convert from Object to int

CODE

<%@ page language="java" import="java.sql.*" import="java.util.*" %>
<html>
<body>
<%
List rowval = (ArrayList)request.getAttribute("data");
Iterator listIt = rowval.iterator ();
while (listIt.hasNext ()) {
    HashMap colval = listIt.next();
    int id;
    for(int i = 1; i <= length.colval; i++) {
    Integer key = new Integer(i);
      String iKey = key.toString();
      if(i == 1){
      id = colval.get(iKey);
      }
      else{
      %>
      <%= colval.get(iKey) %>
<%  
      }
 }
 %>
 <br>
 <%
}
%>
</body>
</html>
0
 
basiranaAuthor Commented:
I am doing something similar to below and trying to access in result.jsp

   /* create our list of maps  */
   ArrayList list = new ArrayList();
   Map map = new HashMap();
   map.put("name", "horse");
   map.put("price", "00.00");
   list.add( map );
 
   map = new HashMap();
   map.put("name", "dog");
   map.put("price", "9.99");
   list.add( map );
   map = new HashMap();
   map.put("name", "bear");
   map.put("price", ".99");
   list.add( map );
   
0
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jaggernatCommented:
instead of   HashMap colval = listIt.next();


try this

HashMap colval = new HashMap();
colval = (HashMap)listIt.next();
0
 
jaggernatCommented:
or  just

HashMap colval = colval = (HashMap)caseIterator.next();
0
 
basiranaAuthor Commented:
Can you please check the error below

Error:

org.apache.jasper.JasperException: Unable to compile class for JSP

An error occurred at line: 4 in the jsp file: /result.jsp
Generated servlet error:
Type mismatch: cannot convert from Object to int


      org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:84)
      org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:328)
      org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:414)
      org.apache.jasper.compiler.Compiler.compile(Compiler.java:297)
      org.apache.jasper.compiler.Compiler.compile(Compiler.java:276)
      org.apache.jasper.compiler.Compiler.compile(Compiler.java:264)
      org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:563)
      org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:303)
      org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
      org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
      javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
      org.apache.jsp.update_jsp._jspService(update_jsp.java:96)
      org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
      javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
      org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
      org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
      org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
      javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
      org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)

Code:

<%@ page language="java" import="java.sql.*" import="java.util.*" %>
<html>
<body>
<%
List rowval = (List)request.getAttribute("data");
Iterator listIt = rowval.iterator ();
while (listIt.hasNext ()) {
      HashMap colval = new HashMap();
      colval = (HashMap)listIt.next();
    int id;
    for(int i = 1; i <= colval.size(); i++) {
    Integer key = new Integer(i);
      String iKey = key.toString();
      if(i == 1){
      id = colval.get(iKey);
      }
      else{
%>
      <%= colval.get(iKey) %>
<%  
      }
   }
 %>
 <br>
 <%
 }
%>
</body>
</html>
0
 
jaggernatCommented:
instead of  id = colval.get(iKey);

try


 id = colval.get(iKey).hashCode();
0
 
jaggernatCommented:
or try this

Integer id;
                                    for(int i = 1; i <= colval.size(); i++) {
                                    Integer key = new Integer(i);
                                     String iKey = key.toString();
                                     if(i == 1){
                                     
                                     
                                     id = (Integer) colval.get(iKey);
                                     }
                                     ...
0
 
basiranaAuthor Commented:
You are the one that works perfect... Thanks
0
 
jaggernatCommented:
u r welcome!
0
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