How to display data from 3 maps in one table in jsp

Question

I have three maps having data in it. How can i display it in a table in jsp page.

Answer 1

Iterate each map using <c:forEach>

<table>
<c:forEach items="#{map1}" var="item1">             
   <tr>       
  <td><c:out value="#{item1.key}" /></td>
  <td><c:out value="#{item1.value}" </td>
  </tr>
</c:forEach>

Answer 2

Merge three Map in to one .

    Map<String, Integer> map1 = new HashMap<String, Integer>();
    Map<String, Integer> map2 = new HashMap<String, Integer>();
    Map<String, Integer> map3 = new HashMap<String, Integer>();

    Map<String, Integer> combinedMap = new HashMap<String, Integer>();
    combinedMap.putAll(map1);
    combinedMap.putAll(map2);
    combinedMap.putAll(map3);

Then Iterate on combinedMap .

    <c:forEach items="#{combinedMap}" var="item1">

Answer 3

There are more than one way to accomplish this (one of them):

By using JSP Standard Tag Library (JSTL) c:forEach Tag as follows:

 <c:set value="${sessionScope.sessionObject.map1}" var="map1">
 <c:set value="${sessionScope.sessionObject.map1}" var="map2">
 <c:set value="${sessionScope.sessionObject.map1}" var="map3">

<c:forEach items="${map1}" var="item1">             
   <tr>       
  <td><c:out value="${item1.key}" /></td>
  <td><c:out value="${item1.value}" </td>
  </tr>
</c:forEach>
<c:forEach items="${map2}" var="item1"> .... etc

Or join them in one map and then iterate.

Answer 4

To solve this problem i used the MultiMap from apache commons collections. This can also be solved if i create a DTO for data to be sent on jsp.