If I have a JSF backing bean return an object of t开发者_StackOverflow中文版ype ArrayList, I should be able to use <c:foreach>
to iterate over the elements in the list. Each element contains a map and although the question of how to access the map content through JSTL has been answered here, if I pass an array of such maps, I can't find how to iterate over them and still access the map content using JSTL. There's documentation which refers to simple iterators but not to those whose items are themselves maps.
If anyone can give me a simple example of how a java List is iterated over in JSP I'd be massively appreciative. Mark
Mark, this is already answered in your previous topic. But OK, here it is again:
Suppose ${list}
points to a List<Object>
, then the following
<c:forEach items="${list}" var="item">
${item}<br>
</c:forEach>
does basically the same as as following in "normal Java":
for (Object item : list) {
System.out.println(item);
}
If you have a List<Map<K, V>>
instead, then the following
<c:forEach items="${list}" var="map">
<c:forEach items="${map}" var="entry">
${entry.key}<br>
${entry.value}<br>
</c:forEach>
</c:forEach>
does basically the same as as following in "normal Java":
for (Map<K, V> map : list) {
for (Entry<K, V> entry : map.entrySet()) {
System.out.println(entry.getKey());
System.out.println(entry.getValue());
}
}
The key
and value
are here not special methods or so. They are actually getter methods of Map.Entry
object (click at the blue Map.Entry
link to see the API doc). In EL (Expression Language) you can use the .
dot operator to access getter methods using "property name" (the getter method name without the get
prefix), all just according the Javabean specification.
That said, you really need to cleanup the "answers" in your previous topic as they adds noise to the question. Also read the comments I posted in your "answers".
try this
<c:forEach items="${list}" var="map">
<tr>
<c:forEach items="${map}" var="entry">
<td>${entry.value}</td>
</c:forEach>
</tr>
</c:forEach>
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