Java class into jsp page

hi i,m a beginnner
how can i run my own java class into a JSP file?
please help me!
thanks

If you understand the OO concepts and wrote the Java class right, then all you need to do is something like:YourJavaClass yourJavaClass = new YourJavaClass();
yourJavaClass.doSomething();After all I rather recommend to use servlets for business logic instead of JSP (read: scriptlets).

Similar Messages

Importing java classes into jsp page

I'm trying to import java classes inside my jsp page, while doing that i am getting compilation error "package uma.natarajan.javaclasses" not found. I don't know where to copy the java files. i'm keeping my jsp files under public_html folder


Hi uma,
          create uma\natarajan\javaclasses under weblogic_home\myserver and copy java
          classes(u want to import) to uma\natarajan\javaclasses and then u try.
          Concept is the java classes u import should be present in a classpath. Hope
          this may help u,
          Arun,
          [email protected]
          "uma natarajan" <[email protected]> wrote in message
          news:3a490bcb$[email protected]..
          > I'm trying to import java classes inside my jsp page, while doing that i
          am getting compilation error "package uma.natarajan.javaclasses" not found.
          I don't know where to copy the java files. i'm keeping my jsp files under
          public_html folder

How to load java class from jsp page?

hi all!
Does anyone know how to load java class from jsp page?
I try to load java class from jsp page.
Is it possible to load java class fom jsp page?
thanks and have a good day!

What I mean is How to load/open java class file from jsp page?
I think we can open Applet from jsp page by using
<applet code=helloApplet.class width=100 height=100>
</applet>
but, how to open java class which is an application made by Frame?
thanks and have a good day

Calling java class from jsp page

Dear Friends.
I wrote jsp page and java class.
Am calling java class from jsp page. after processing result,
I have to refresh jsp page from java class.
processing time may take 5 minutes or 1 minute etc. that depends on user.
Can It be possible ? if possible , How ?

Ok, I get a very strange error now:
org.apache.jasper.JasperException: Unable to compile class for JSPerror: An error has occurred in the compiler; please file a bug report (http://java.sun.com/cgi-bin/bugreport.cgi).
What is this??? Anyone?

Import java-classes in JSP-page

Hi,
I'm starting with JSP and with trying one of the first examples in the book "beginning J2EE 1.4" from wrox, i got following problem.
i'm trying to import a java-class in the package CH03 with
<%@ page import="Ch03.FaqCategories" %>but he didn't find the package Ch03.
I try already many things and i have no idea of the cause of the problem. So it's difficult to give information that leads to the solution.
Maybe helpfull is the direcory-structure:
jsp-page: /Ch03/welcome.jsp
java-classe: /Ch03/WEB-INF/classes/Ch03/FaqCategories.class
If you need source-codes or other information, just ask.
Thanks,
Dennis

Thank you,
Your help was one step into the good direction and that problem is solved.
The application work now with studio one, but if i try it to work it with a stand-alone tomcat server it doesn't work anymore. I go first try to solve this problem by my self or at least try to describe the problem more exactly, before i ask for new help.
but if you have any idea, that's always welcome...
with regards,
Dennis

Tag to take a java class in JSP page

Hi,
� need to get a tag to get a java class for example Test.java into a JSP page like MyJSP.jsp so that � can ,after doing this, call its methods, variables etc.
Thank you !

� know a way to do th�s us�ng JRun but the programme � have (NETBEANS IDE 3) does not accept �t.

How to use java class in jsp page of JSPProvider?

Hello everybody.
I created simple JSPProvider channel with portal amconsole and named it "jspprov1". Then I created "jspprov"1 directory under "/ets/opt/SUNWps/desktop/sampleportal". I put "index.jsp" in it. And it worked until I add this line into "index.jsp": <% @page import="jspprov1package.aclass1" %>. Then I created directory "jspprov1package" under "/ets/opt/SUNWps/desktop/classes" and put "aclass1.class" into it and into "/ets/opt/SUNWps/desktop/classes" itself. I created "aclass1.class" on the other machine (with no installed portal) in j2sdk1.4.1_02: "javac aclass1.java". The text of this class is simple:
"package jspprov1package;
public class aclass1{
public int int_field = 10;
But the page still don't work. It writes on the portal desktop "ERROR: Content is not available".
Does anybody know why this happened?

Sorry, there were mistakes in jsp page and java files.
I maked the channel "show exceptions" and found them out.

Importing classes into JSP page

Hi There,
I am new to this and here is my problem.
I am doing a shopping cart tutorial and trying to get a JSP page to import two classes :
<%@ page language="java" contentType="text/html"
import="ShoppingBasket,Product"
errorPage="errorpage.jsp" %>
I get :
C:\jakarta-tomcat-4.1.30\work\Standalone\localhost\_\shop_0002dbasket_jsp.java:7: '.' expected
import ShoppingBasket;
^
C:\jakarta-tomcat-4.1.30\work\Standalone\localhost\_\shop_0002dbasket_jsp.java:8: '.' expected
import Product;
^
C:\jakarta-tomcat-4.1.30\work\Standalone\localhost\_\shop_0002dbasket_jsp.java:50: cannot resolve symbol
symbol : class ShoppingBasket
location: class org.apache.jsp.shop_0002dbasket_jsp
ShoppingBasket basket = null;
The classes compile ok . I read that instead of comma seperating the classes it might be better to put them in a package but I do not know the correct syntax or where to put the package if this is correct.
The tutorial is from this book and the shopping cart source code is here.
http://www.ineasysteps.com/books/?1840781971
Any help appreciated
Jim Ascroft

A little beginners explanation of classpaths and packages is in order here. A package works like an extension of the name to keep class names unique. For example, if you have a ShoppingBasket.class and you want to use my ShoppingBasket.class along with it the two class names must be unique or different from one another in some way. Yours could be in com.yourcompany package and mine could be in org.mycompany package. When you reference you Shopping backet in your code you would use com.yourcompany.ShoppingBasket and when you reference mine in the same code you would use or.mycompany..ShoppingBasket. Shorthand for the class can be used by adding an import at the top of the referencing java file. An import is like saying "hay compiler, whenever you see ShoppingBasket look for it in the com.mycompany package!" That brings us to the next point. The package name must always be reflected in the directory structure of the .class file location in order to be found. Your shopping basket must be stored under the directory com/yourcompany if it is in package com.yourcompany. That directory structure should extend off of a classpath entry in order to be made available to the JVM. Classpath entries point to folders, jar or zip files that contain packaged and unpackaged classes. So If you have a classpath entry that points to C:\jakarta-tomcat-4.1.30\webapps\ROOT\WEB-INF\classes then all unpackaged classes (classes compiled from a .java file without a package statement) will be pulled directly out of this folder. Also, packaged classes will be pulled out of they're packaging directory structure, which should be located in this folder. You can have as many classpath entries as you want but the classes will be pulled out of the first entry that they can be found under. Now with a web app you don't normally fuss with the setting of classpaths since they are already predefined and configured for you. You just need to know to put all of your class files under the WEB-INF/classes directory in the root of your web app. You do, however, still need to know how they work. You also should know that any jar files should be placed in the lib folder of your web app and not under the classes folder.
Getting back to your immediate problem, why are you getting class not found errors? Well this stems from what was said above. To fix these kind of problems follow these steps:
1st off, find out exactly which .java file the .class file was compiled from. (This can be a problem in some environments where multiple copies of source hang around.) This step may involve a recompile and paying close attention to the compiler arguments. In an IDE there should be a setting or dialog that lets you find out exactly where it's placing the .class files created from you source.
Next, determine what package the .class file should be in by examining (and maybe changing) the package statement at the top. For example, if you intended to put ShoppingBasket in the com.bloodoo package make sure it has a package "com.bloodoo;" statement at the top.
Next recompile the .java source and move the packaging directory structure into the classes folder of your app. (This would be WEB-INF/classes under the root of the web-app.) For example if ShoppingBasket.class was compiled into the com/bloodoo folder under C:\Program Files\YourIDE\projects\yourproject\output then copy the com folder out of the output folder and into the WEB-INF\classes folder.
Next examine the calling code (JSP or servlet .java code) and make sure it references the problem class out of the right package. For example, yourpage.jsp should reference the class com.bloodoo.ShoppingBasket and not ShoppingBasket if the shopping basket is deployed in package com/bloodoo. This gets tricky with jsp usebean tags because the desire is to use shorthand but I'm not sure if that works with the use bean tag. Make any modifications and recompile if necessary.
Lastly, as a rule of thumb avoid wild-card imports (eg. import com.package.*) because they are a common cause of confusion especially when refactoring package names and resolving these kind of issues.Those steps should allow you to resolve 85-90% of your class not found issues. The other 10-15% are rare cases involving the use of custom classloaders, the Java extension mechanism and/or classpath trickery. If you still have questions/problems post back.
Cliff

Ordinary java class and jsp page

hi i want to use some java class(not javabean ) in my jsp . how do i import them and use them?

You can just import the package into your JSP, and access it like any other class of the Standard Java API that you access.
fun_one

Passing parameters from a Java class to Jsp page

Hi everybody. I'm newbie in using Java class in conjunction with JSP pages. Infact I have a problem. How can I pass the parameters used in a Java class (as UserName, Password, and so on..) to a JSP page? What methods (and classes) I have to use?
Thank you in advance
Have a nice day

It still doesn't work. I write the code
//my java class
package channel_service;
import java.util.Vector;
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2002</p>
* <p>Company: </p>
* @author unascribed
* @version 1.0
public class CallMenu {
private Vector parameters = new Vector();
public void setParameters( String UserId ) {
parameters.add(0, UserId);
//parameters.add(2, Pin);
//parameters.add(3, UserName);
//parameters.add(4, Greeting);
public Vector getParameters() {
return parameters;
//my jsp page
<%@ page import="Channel_Service.src.channel_service.CallMenu" %>
<%@ page import="java.util.Vector" %>
<html>
<head><title>User Menu Page</title></head>
<body>
<center><h1><i><b>This is your personal User Menu page</b></i></h1></center>
<br>
<br>
<center><h2><i>In the list below you'll find all your personal information (as UserID, Password and so on...)
and all the function you have the rights to use</i></h2></center>
<br>
<br>
<table align=center>
<tr>
<%
CallMenu cl = new CallMenu();
cl.setParameters();
Vector params = cl.getParameters();
String UserId = (String)params.elementAt(0);
String Pin = (String)params.elementAt(1);
String UserName = (String)params.elementAt(2);
String Greeting = (String)params.elementAt(3);
%>
<td><h2><b><i>User ID = <%= UserId %></td></tr>
<tr><td><h2><b><i>PIN = <%= Pin %></td></tr>
<tr><td><h2><b><i>User Name = <%= UserName %></td></tr>
<tr><td><h2><b><i>The system says <%= Greeting %></td></tr>
</table>
</body>

Scope of a java class in JSP page

Hi
If I use a java bean using the
<jsp:useBean
id="beanSomeName"
scope="page|request|session|applicaton
I can specify the scope of of the bean after which I can assume it is Garbage Collected.
However if I just create a new Java Class in a jsp bean ( I inherited this code ) what will be scope of this java class. When will it be Garbage collected.
Is it Page scope?
Thanks
bib/-

If you do
<% MyClass c = new MyClass(); %>
and don't do anything else to store it in the request or session than it is like page scope.
if you do
<%! MyClass c = new MyClass(); %>
it is more like application scope.

Calling my Java class from JSP page

Hello, I am trying to call my Java class from my JSP page passing parameters to it and getting back a collection of result sets. Can someone tell me what I might be doing wrong:
JSP code to call Java class:
<%
String strEssUser = "test";
String strProcessingMonth = "JUL";
String strProcessingYear = "2002";
strQueryList=new ListReturn(strEssUser.toString(), strProcessingMonth.toString(), strProcessingYear.toString());
%>
I get this error when I try to run this JSP page using tomcat:
C:\Program Files\Apache Tomcat 4.0\work\Standalone\localhost\em\jsp\Test_0005fSummarySBU_0005fscreen$jsp.java:77: Class org.apache.jsp.ListReturn not found.
strQueryList=new ListReturn(strEssUser.toString(), strProcessingMonth.toString(), strProcessingYear.toString());
I'm not sure if this problem is the way I am calling the Java class, or if I have a problem in the Java code itself. Can anyone help?

Ok, I get a very strange error now:
org.apache.jasper.JasperException: Unable to compile class for JSPerror: An error has occurred in the compiler; please file a bug report (http://java.sun.com/cgi-bin/bugreport.cgi).
What is this??? Anyone?

Sharing java class among JSP pages. Urgent!

Hi,
I have a class A and two JSP pages P1 and P2 page.
i need to share the class values in both the pages.
that is, whatever am doing in class A through P1 should be impacted on P2.
Please tell me how to do this.
Thaks,
Raja.

Well then you might try
session.setAttribute("myBean", myBean);and
MyBean myBean = (MyBean) session.getAttribute("myBean");The session is common space for storing the user's objects if you want to keep them over multiple requests.
The session is implicitly available to all JSPs and via the Request object in a servlet.
If the information is common to all users, another alternative may be to implement it as a Singleton bean - or have a static instance of it. But that may not be what you actually want.

Using java class from JSP page

I have a class that connects to the database and return the result in form of array of objects, now I wrote a tester and I was able to print the result on the console but when it came to JSP how can I use this class I am a bit confused, how can I declare an array of objects and save the result that comes from the class method
note: my class is not a bean it is a service class that contain methods to retreive different information from the database.
I would apritiate any help but please make it in sequence for example declaring an array to hold the result then call the method that returns the array of objects..etc
please help, I am really confused and don't know what to write
thank you

You can access a class in the same way as a bean, after all a bean is just a class that follows a set of rules.
You need to put your classes in packages to access them.
I have 2 packages, params and DTO. I set the class that returns the Data Transfer Object, or array of objects up as I would a bean
<jsp:useBean id="DTO" scope="request" class="params.DTO" />
I think you skip the above declaration and access it directly in code using
params.DTO();
but setting it up as I would a bean allows me to simply use
DTO();
DTO is the class that passes back the array of objects.
Objects themselves I have in a seperate package, also called DTO (sorry if this is confusing, made sense at the time :-) ) You dont need them in seperate packages, just helped me keep DTO objects seperate from business logic classes......
Now before I use params.DTO() I declare a variable of the Object type DTO() returns
<%! DTO.workSheet[] ws; %>
So, ws is the object type that will be returned by params.DTO()
Then to get my array of objects back from params.DTO() :-
ws = DTO.workSheet(day);
or if you dont like the bean declaration
ws = params.DTO.workSheet(day);
You need to put your packages under WEB-INF/Classes when using Tomcat
So I have
Tomcat 5.0\webapps\myApplication\WEB-INF\classes\params
Tomcat 5.0\webapps\myApplication\WEB-INF\classes\DTO
Under which reside the classes

Passing vector between java class and jsp page

Hi,
I think this is similar to the last post but anyways maybe somebody can help us both out bontyh.....I am getting an error saying undefined variable or class when i try to access a Vector which was returned in a class.
Anyways anyone got any ideas?

Maybe if you give some more information...

Java class into jsp page

Similar Messages

Maybe you are looking for