Primefaces Dataexporter and get method - jsf-2

Question

With a simple class wich contains only a list of list of String, I can view all its elements in a p:dataTable with the get(int) method of class List but it fails when I try to export this with the p:dataExporter component.
Here's the Java source code :
#ManagedBean
#SessionScoped
public class MainClass {
private List<ArrayList<String>> listOfListOfString;
public List<ArrayList<String>> getListOfListOfString() {
return listOfListOfString;
}
public void setListOfListOfString(List<ArrayList<String>> listOfListOfString) {
this.listOfListOfString = listOfListOfString;
}
public MainClass() {
listOfListOfString = new ArrayList<ArrayList<String>>();
ArrayList<String> firstList = new ArrayList<String>();
firstList.add("a");
firstList.add("b");
listOfListOfString.add(firstList);
ArrayList<String> secondList = new ArrayList<String>();
secondList.add("1");
secondList.add("2");
listOfListOfString.add(secondList);
}
}
And the XTHML code :
<h:body>
Hello from Facelets
<h:form prependId="false">
<p:dataTable id="tbl" var="myList" value="#{mainClass.listOfListOfString}" paginator="true" rows="10" >
<p:column headerText="First column">
<h:outputText value="#{myList.get(0)}"/>
</p:column>
<p:column headerText="Second column">
<h:outputText value="#{myList.get(1)}"/>
</p:column>
</p:dataTable>
<h:commandLink value=" csv">
<p:dataExporter type="csv" target="tbl" fileName="userList" />
</h:commandLink>
</h:form>
</h:body>
And the error stack when I click on the csv link:
For input string: "get"
- Stack Trace
java.lang.NumberFormatException: For input string: "get"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
at java.lang.Integer.parseInt(Integer.java:449)
at java.lang.Integer.parseInt(Integer.java:499)
at javax.el.ListELResolver.coerce(ListELResolver.java:173)
at javax.el.ListELResolver.getType(ListELResolver.java:72)
Do you have an idea why p:dataTable can use the get(int) method and p:dataExporter can't?
Thanks,
Philippe

Answer 1

Probably both components are implemented differently.
But you can access list elements this way:
#{myList[n]}
where n is the list index.