jsp problem - ArrayList or Vector
hey, im new to java servlets and jsp - im doing some school project (web application) with java servlets and i got stuck - i need to send some data through session set/get Attribute, i made ArrayList but dont know how to initizalise Array list within jsp. i have following Arraylist
ArrayList<Sales> salesLst;
salesLst=new ArrayList<Sales>();
ArrayList<String> productName;
productName=new ArrayList<String>();
ArrayList<String> username;
username=new ArrayList<String>();
they are all submited to jsp via
session.setAttribute("salesLst", salesLst);
session.setAttribute("productLst", productName);
session.setAttribute("userLst", username);
so how do i create ArrayList of Sales, productName and username in jsp? tnx in advance
or should i got with Vector class?
PS some example code will be more than welcome
tnx
[941 byte] By [
auZa] at [2007-11-26 17:33:52]
# 1
If you use JSP scriptlets inside a JSP all you have to do is enclose Java code inside
<%
%>
so in your case it would be:
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%
ArrayList<Sales> salesLst;
salesLst=new ArrayList<Sales>();
ArrayList<String> productName;
productName=new ArrayList<String>();
ArrayList<String> username;
username=new ArrayList<String>();
salesLst = session.getAttribute("salsLst");
// similarly the other two ArrayLists
%>
As you become more familiar with JSPs , you can start learning JSP Tag Libraries (JSTL) - since its the new and improved way of writing JSPs.
Although I don't really know how to use ArrayLists with JSTL in JSPs, but I guess there's probably a way to use them with JSTL.
Many articles suggest not to use Vectors since they are synchronized - using ArrayList is much better than using Vectors.
Message was edited by:
appy77
# 2
Just a couple of pitfalls with using this code in JSP on Tomcat.
The current compiler distributed with Tomcat5.5 is the JDT compiler.
I believe that is still only JDK1.4 compliant
ie - you can't use Java1.5 syntax in a jsp page, unless you change the internal compiler used by Tomcat
You set this in the [TOMCAT]/conf/web.xml configuration file .
In any case, scriptlet code in a JSP is discouraged.
Put that code in a Servlet/Bean/Struts action.
About the only thing you can do with a list in JSTL is read it.
You can not set values into a list using JSTL.
Of course if you are wanting to set values into a list, the code shouldn't be in a JSP anyway.
Cheers,
evnafets
# 3
tnx for the help but tomcat has thrown exception for jsp file
<%@page import="java.util.ArrayList"%>
<%!
String date;
ArrayList<data.Sales> salesLst; //sales class is in the data package
salesLst=new ArrayList<data.Sales>();
%>
<%
date = (String)session.getAttribute("date");
salesLst=(ArrayList)session.getAttribute("salesLst");
%>
<html>
<head>
<title>Orishlajm cosmetics :: sales on <%=date%></title>
</head>
<body>
<a href="onDateSales.jsp">select another date</a>
<a href="loginAdmin.jsp">choose another option</a>
<a href="index.jsp">back to login</a>
<a href="javascript:window.print()">print this page</a>
</body>
</html>
and the exception is
An error occurred at line: 5 in the jsp file: /onDateSold.jsp
Generated servlet error:
Syntax error on token ";", , expected
but when i comment part with ArrayLIst it works
Message was edited by:
auZ
auZa at 2007-7-9 0:01:53 >
