how to handle ResultSet from jsp?
Hi there,
I use a servlet to query the db and put the result into a Vector v of beans(each bean represents one row in the ResultSet). The Vector v is then put in the request by setAttribute() and forward to the display.jsp. In the display.jsp, I tried
<%@page import="java.util.*,Financial.TransactionBean" contentType="text/html"%>
<%@page pageEncoding="UTF-8"%>
<jsp:useBean id="transaction" class="Financial.TransactionBean" scope="session"/>
//cut off...
<body>
<ul>
<%
Vector v = (Vector)request.getAttribute("list");
Iterator i = v.iterator();
while (i.hasNext())
{
transaction = (TransactionBean)i.next();
%>
<li>
<%-- <a href="CORE/Financial/FinancialServlet?cmd=get&id= --%>
<a>
<jsp:getProperty name="transaction" property="id" /> ">
<jsp:getProperty name="transaction" property="day" />
<jsp:getProperty name="transaction" property="amount" />
</a>
<% } %>
</ul>
//cut off....
I though for every bean in the Vector, i can extract it's properties but I got an error :
Cannot find any information on property 'id' in a bean of type 'Financial.TransactionBean'
What can possibly go wrong?
# 2
You r right, the getID() wasnt recognized as accessor it should be getId() - the capitalized "D" is the source of error.
However, after i change it, it doesnt seem that the bean (null) i create in the display.jsp file is referenced to the actual bean objectin the Vector as instructed in the <%%> tags. Thus, using <jsp:getProperty name="transaction" property="day" /> always give null.
Is there any other way to send the resultSet to jsp and display all record in it?
I was thinking about creating a list bean which contains many bean, each coresponds to a record and overwrite the toString() method for the list bean so that it return a well format of all record. However, this way doesnt give me the flexibility of formating data inside the bean.
Hope anyone have a suggestion
# 3
how about dumping the very aged scriptlets and switching to the use of JSTL? JSTL has an "sql" tag library with which you can work with database queries in a JSP, if you really want to do that.
For example, check this link:
http://www.ibm.com/developerworks/java/library/j-jstl0520/
# 5
Servlet centric design is fine, and in fact preferred.
I would probably use a List (ArrayList) rather than a Vector but thats really just semantics. They are the same thing in effect, but ArrayList is "newer" and "better"
Your mistake in the page is mixing up scriptlet variables with <jsp:property> tags.
You have declared a scriptlet variable "transaction"
This has no direct relationship to a bean "transaction" - you can't access it directly via the <jsp:getProperty> tags.
If you want to retain the scriptlet code, then use
<%= transaction.getId() %> rather than <jsp:getProperty> tag for it.
The preferable way is to use JSTL <c:forEach> loop to eliminate the scriptlet code:
<body>
<ul>
<c:forEach var="transaction" items="${list}">
<a href="CORE/Financial/FinancialServlet?cmd=get&id=${transaction.id}">
${transaction.id} ${transaction.day} ${transaction.amount}
</a>
</c:forEach>
</ul>
...
