<c:forEach var="user" items="${users }">
<form action="user_update_Users">
<tr>
<td> <input name = "user.id" value="${user['id'] }" readonly="readonly"></td>
<td> <input name = "user.userId" value="${user.userId }" readonly="readonly"></td>
<td> <input name="user.userName" value="${user.userName }"></td>
<td> <input name="user.password" value="${user.password }"></td>
<td> <input name="user.userType" value="${user.userType }"></td>
<td> <input type="submit" value="修改"></td>
</tr>
</form>
</c:forEach>
form一定要放在forEach里面,表示要提交的表单。