Struts, Logic:Iterate & ArrayList of ArrayList of Strings

[Alex Lau]

Hi,

I was wondering if someone could help me with a problem I'm having. Part of my web application requires that I allow the user to choose the columns he wishes to perform an SQL query on.

Because I can't use <bean:write property=".../> tags (what columns the application shows in the table will change according to the query performed), I chose to create an ArrayList of ArrayLists of Strings where each string should represent one element of one row.

I declare my ArrayList of ArrayList of Strings as follows:

private java.util.ArrayList<java.util.ArrayList<java.lang.String>> employeeList = new java.util.ArrayList<java.util.ArrayList<java.lang.String>>();

Inside of a while loop in the same class, I create new employee records:

while (rs.next())
{
ArrayList<String> employee = new ArrayList<Employee>();
employee.add(rs.getString(1));
...
employee.add(rs.getString(19);
this.employeeList.add(employee);
}

The employeeList is then returned:

return employeeList;

In my action class, I declare an ArrayList:

private ArrayList employeeList = new ArrayList();

And I call on the method above to fill it with the appropriate data:

employeeList = a.doPost(...)

And set it to the session:

session.setAttribute("sqlemployees", employeeList);

On my results page:

<logic:iterate id="employee" name="sqlemployees">
  <tr>
    <logic:iterate id="element" name="employee" indexId="index">
      <td>
        <bean:write name="element"/>
      </td>
    </logic:iterate>
  </tr>
</logic:iterate

>

which returns a org.apache.JasperException:

javax.servlet.ServletException: Cannot find bean: "element" in any scope
javax.servlet.jsp.JspException: Cannot find bean: "element" in any scope

If I iterate through the index, numerical values (0,1,2,3...18) will show with the correct number of records (19). If I bean:write the employee itself, it will show as [element1,element2...].

I'd really appreciate any help I can get!

Thanks in advance,
Alex

[Alex Lau]

Solved it

Thanks anyways =]

[Brent Sterling]

hmmm...nothing jumps out at me. I have not used generics much and never with nested collections. It seems like it should work fine. Is this valid code or just a post error?
ArrayList<String> employee = new ArrayList<Employee>();

About all I can say it to make sure you have taglib directive for logic. I am not sure how many hours I have wasted tracking down issues that turned out to be this simple mistake.

- Brent