Question

I have a servlet ( that I cannot change ) to gather information to be displayed in on a web page. I use a bean in a JSP page to loop through the information.

I tried to simplify, but my information is stored tables basically like this
alt text http://img36.imageshack.us/img36/4295/schemase.jpg

So for example, the bean stores information in nested arrays like this:

---2009
------TOYOTA
---------BLUE 10
---------RED 20
------CHEVY
---------BLUE 30
---------RED 10
---2010
------TOYOTA
---------BLUE 30
---------RED 12
------CHEVY
---------BLUE 12
---------RED 20

This is great for when I display the report per year, per category, per color. I can easily loop through the years, loop through the categories, then loop through the colors. This is the report I have ( simplified )
alt text http://img841.imageshack.us/img841/3666/reportihave.jpg

Now I need to turn that information sideways. I need to create a report to display the count per color, per year. This is the report I need:

alt text http://img33.imageshack.us/img33/461/reportineed.jpg

How can I rearrange the information within the JSP? Should I use arrays to gather the info, or is there an equivalent to a hash that I can use?

Thanks

Answer 1

I solved the problem by looping though the lists in the bean until I got to the color list, then started looping through again and again until I found all the records for each color.

<c:forEach var="year1" items="${Info.list}"  varStatus="yearCounter1" >
    <c:if test="${yearCounter1.count == 1}">
        <c:forEach var="clist1" items="${year1.list}" varStatus="catCounter1">   
            <c:if test="${catCounter1.count == 1}">
                 <c:forEach var="colorlist1" items="${colorlist1.list}" varStatus="colorCounter1">
                                 <!-- this gets me to all possible colors -->
                                 <c:forEach var="year2" items="${Info.list}"  varStatus="yearCounter2" >
                    <c:forEach var="clist2" items="${tlist2.list}" varStatus="catCounter2">
                                             ....
                                                          <c:if test="${colorCounter1.description==colorCounter3.description&& year2.description==year3.description  && clist2.description==clist3.description}" >

Is it efficient? No.

Is it a good use of JSTL? No.

But I am stuck. I cannot change anything in the bean, I had to use JSP to do the work.