Java Beans requirement

Hi everybody,
I want to use java beans to make code reusability, but I need arguments to explain their benefits so I need to be more informed about:
- what using java beans demand in terms of technical tools
- and whatever can help me to present their benefits
I am also all ears for whatever you think usefull in this case
thanks a lot in advance

No, using java beans does not require you to use any tools. Any java bean can be called like any other java class.
The benefit is if you use java beans, you can make use of tools to reduce your development time, and the code you write will be more reusable because it handles change better.

Similar Messages

Weblogic 6.1 SP2 Caching Java Bean

Hi,
It seems like Weblogic 6.1 SP2 caches Java Bean, because any changes in Java Bean requires restart of the Instance. Is there any alternative to it , i am sure there will be..
waiting for reply .

Nope don't think so.
Any time you change the code of your javabeans, you need to redeploy them on the server - that normally requires a restart to pick up the changes.
Its the same with Tomcat and JRUN.

JAVA beans and JAVA related services require Oracle client to be installed?

Can you please advice whether an application server that make use of JAVA beans and JAVA related services require Oracle client to be installed? For an example if the solution build based on Java and JBOSS to be used as application server, do we still require oracle client to be installed and configure the tnsnames in order to communicate to database server?

SHANOJ wrote:
Can you please advice whether an application server that make use of JAVA beans and JAVA related services require Oracle client to be installed? For an example if the solution build based on Java and JBOSS to be used as application server, do we still require oracle client to be installed and configure the tnsnames in order to communicate to database server?Oracle client is not required when JDBC is used to connect to the remote DB

Help required in building up the Java Bean for an XML data

Hi ,
I want to build a Java bean which will actually represent an xml data . The class will be named as User and it will typically represent the data in the follwing xml:
<user>
<cwsId>barbete</cwsId>
<firstName>William</firstName>
<lastName>Barber</lastName>
<status>true</status>
<role>
<roleCode>1000000177</roleCode>
<roleName>Customer Administrator</roleName>
</role>
<language>en</language>
<country>US</country>
<preferences>
<equipmentGroup>2717</equipmentGroup>
<dateFormat>MON-dd-yyyy</dateFormat>
<timeFormat>HH:MI AM</timeFormat>
<timeZone>-12:00</timeZone>
<daylightSavings>Y</daylightSavings>
<location>NC</location>
<recordsPerPage>10</recordsPerPage>
<historyPeriod>3</historyPeriod>
<distanceUnit>MILE</distanceUnit>
<fuelUnit>G</fuelUnit>
<unitIdDisplay>E</unitIdDisplay>
<smuUpdate>W</smuUpdate>
<countries>
<country>
<countryCode>GB</countryCode>
<countryName>UNITED KINGDOM</countryName>
</country>
<country>
<countryCode>US</countryCode>
<countryName>UNITED STATES</countryName>
</country></countries>
</preferences>
</user>
Now for single child nodes like cwsId of the main user node i have kept properties like
private String cwsId;
But i am not sure as to how to represent the nodes which contain subnodes like "preferences"node. Any ideas?What is the standard practice?

One thing you could do is create an object model first, which will contain all the data for your user.
then all you need in the bean is a Hashtable with the name of the user as a key, and the user-object (which is actually the complete object model) as a value.
with the XML stated by you, you would get an object model something like this:
Class User
    String cwsid;
    String firstName;
    ArrayList<Role> roles = new ArrayList<Role>(); //I'm assuming a user can have more then one role.
    ArrayList<Country> countries = new ArrayList<Country>();
class Role {
    String code;
    String name;
class Country {
    String code;
    String name;
}And so on for all the varioous elemets of your XML.

What is the difference between java direct or java bean in JSP?

What is the difference if I use java code directly in JSP or use java bean in JSP?
Which class to use for receiving the passed parameter from html or java script? Any difference for java code and java bean in the way receiving the passed data?
How can I pass string from jsp to html or java script?

it's generally accepted as better design to separate presentation from logic. meaning, the java code in the jsp should be used to support displaying data, as oppsoed to implementing the application - like database access, etc.
when the logic is separated from the presentation, it allows you to reuse logic components within several jsp pages.
if you decide to change the presentation layer in the future (to support wap, for example) you don't need to rewrite your entire application, since the "guts" of the application is outside of the jsps.
it is also a good idea to separate your business logic from your data layer. adding a "buffer zone" between these layers helps in the same manner as in separating presentation from logic. if you're using flat files for storage now, upgrading to a database wouldn't require rewriting all your business logic, just the methods which write out the data to a file, for example.
once you feel comfortable with separating the various layers, check out the struts framework at http://jakarta.apache.org/
to answer your second question, to get parameters passed in from HTML forms, use ServletRequet's getParameter() method.
in tomcat:
<% String lastName = request.getParameter( "lastname" ); %>
to answer your third question: when displaying the HTML from withing a jsp, print out the string to a javascript variable or a hidden form element:
<% String firstName = "mike"; %>
<input type="hidden" name="firstname" value="<%= firstName %>">
<script language="javascript1.2">
var firstName = "<%= firstName %>";
</script>
this jsp results in the following html:
<input type="hidden" name="firstname" value="mike">
<script language="javascript1.2">
var firstName = "mike";
</script>

Urgent : java bean having bidirectional one to many relationship

Hi,
We have complex requirement in our application.
We need to copy java bean having bidirectional one to many relationship to another javabean having bidirectional one to many relationship..
E.g
Class Basket1 {
public String color;
pubic String type;
public List<Basket1> basketList = new ArrayList()
Class Basket2 {
public String color;
pubic String type;
public List<Basket2> basketList = new ArrayList()
We need to exact copy Basket1 to Basket2. We are in trouble to copy List of child because we do not have how many child Basket1 have of same type..
Can someone help us how we can implement such kind of complex object bidirectional one to many relationship??

I can't see anything bidirectional about these relationships. What I can see is a couple of BasketN classes that look identical so I don't know why they both exist, and they both contain lists of themselves as members, which suggests some kind of tree structure. Nothing bidirectional there. I can see tat these things can form circular object graphs but I don't see why you would want to do that.
We need to exact copy Basket1 to Basket2And I don't know what that means. Please explain.

Create XML dynamically from schema and Java bean

Hi,
I'm looking for suggestions on the best approach to create an XML file programatically from a schema and Java bean.
The schema used is not fixed and may vary with each request so a dynamic way to create the XML is required.
Is there an API available that allows me to achieve this easily? Any help would be appreciated to point me in the right direction.
Thanks.

XMLBeans or JAXB should work for you.
- Saish

Upload to Excel using Java Bean

Hi
My requirement is that to upload the data to an excel sheet from a JTable(JTable is actually a java bean which gets its input from forms) and the user need to be given either to view the excel/save the excel/print the excel in any of the networked printers.
Please cud someone help me with their inputs.
Thanks again
Deepa

can you send me your code bean and form?
I have example that i can send you to export to excel using webutil and OLE object.

Runtime in Java- Beans

I have the requirement to write a Java- Bean, which calls a command line Application on the Client. The Problem is: if I call a command- line Application, it seems that Java grabs the Input and Output- streams (I dont see anything in the command line Application; if I call a Windows Application it seems to work).
I cant use getInputStream()/getOutputStream, because I can write data only in the Java- Console Window, not in the Console Window I opened before...
Its also not useful to start a new process using the command line (cmd /c start sqlplus), because after starting the process the called console window closes, and the JavaBean continues with execution (very very bad...)
plz help me ;)
thanks

uhm...that seems to work, yes, but...
I have solved the problem in a Client App with this Topic, but it I have a JavaBean on an Oracle iAS, and if I use System.out.println, then I get the output in the Java- Console Window OF THE BROWSER, not in the Console Window I just called...
I just want to call a simple sqlplus command line client, create packages in the Oracle Database and see in this window how the packages are created/ if there are errors etc.

Using Java Beans in Java Server Pages

Can we not use a method of Java Bean in a Java Server Page ?
I am trying to retrieve the user email from a java bean method "getUserEmail". I am instantiating the class, but when I try to use that in JSP tags, I am getting an error.
<jsp:useBean class = "formjavabean.application" id = "applicationId" scope = "session" />
<%@ page import="java.io.*, java.lang.*" %>
<%!
String user = applicationId.getUserEmail() ;
String f3 = "ftn03" ;
String f3not = "ftn03 file not uploaded";
...........I am failing in debugging that, can anyone help plz ?

Here is my whole code in parts:
First the head section:
<head>
<title> Fastran </title>
<jsp:useBean class = "formjavabean.application" id = "applicationId" scope = "session" />
</head>JSP part in the body section :
<%@ page import="java.lang.*, java.io.*" %>
<%!
private String f3 = "ftn03";
private String f3not = "ftn03 file not uploaded";
private String f7 = "ftn07";
private String f7not = "ftn07 file not uploaded";
private String f9 = "ftn09";
private String f9not = "ftn09 file not uploaded";
public String checkFile3()
    File ch3 = new File("C:\\JBoss\\jboss-4.0.5.GA\\bin\\Fastran\\ftn03") ;
    if (ch3.exists() == true)
        return f3 ;
    else
        return f3not ;
public String checkFile7()
    File ch7 = new File("C:\\JBoss\\jboss-4.0.5.GA\\bin\\Fastran\\ftn07") ;
    if (ch7.exists() == true)
        return f7 ;
    else
        return f7not ;
public String checkFile9()
    File ch9 = new File("C:\\JBoss\\jboss-4.0.5.GA\\bin\\Fastran\\ftn09") ;
    if (ch9.exists() == true)
        return f9 ;
    else
        return f9not ;
%>Java Script in the body section, using methods defined in the JSP part:
<script type="text/javascript">
        function validate_file ( )
                var file3 = "<%= checkFile3() %>" ;
                var file7 = "<%= checkFile7() %>" ;
                var file9 = "<%= checkFile9() %>" ;
                if ( file3 != "ftn03" || file7 != "ftn07" || file9 != "ftn09" )
                    alert("Please upload the required file") ;
                    return ("fastran.jsp") ;
                else
                    return ("processForm.jsp") ;
        function validate_upload ( )
                valid = true;
                if ( document.val_file.filefield.value == "")
                        alert("Please select a file for upload") ;
                        valid = false;
                return valid;
    </script>Finally the form and button part of the page, in the body section:
<form name = "val_file" method="post" action="upload.jsp" name="submit" enctype="multipart/form-data" onSubmit = "return validate_upload();">
Upload Files: <input type="file" name="filefield" >&nbsp&nbsp<input type="submit" name="submit" value="Upload"><br>
<font color = "Red"><h5>(ftn03,ftn07, and ftn09)</h5></font><br><br><br>
Files on the server :<br><br>
<font color = "Green"><h5>
<%= checkFile3() %><br>
<%= checkFile7() %><br>
<%= checkFile9() %><br>
</h5></font>
<br><br><br><br><br><br><br><br><br>
<input type=button onClick="location.href='logintest.jsp'" value='Home'> <input type=button onClick="location.href=validate_file()" value='Proceed' ><br>
</form>Now try this:
Change <%! to <%, or try using bean method as:
String userEmail = applicationId.getUserEmail() ;..........and that is my problem. I would really appreciate any help, thanks

Java bean for database access

Hi,
I am writing a JSP/servlet/Javabean based app. using MVC architecture.The database related logic is in java beans.
I want a generalized class/bean that can form a connection , execute the passed query and return the results.Does any one has any URLs or sample code to explain how to do this using introspection?
I would greatly appreciate any help as this design is very crucial for our application.
Thanks -
k

i don't think it need help,every book has such code,maybe i haven't understanding your meaning correctly,follow steps:
1 create a class named DBconnect,
2 in the constructor of the class,you create the connection,
3 add several methods that execute the operation into your class ,such as :executeQuery(),executeUpdare().....
that depands the requirement of your project.

Using java.beans.EventHandler to create javafx.event.EventHandler instances

One thing I do not like about the JavaFX EventHandler is all the anonymous classes that need to be created. This messes up the way the code looks and I heard that creating all these anonymous classes adds to the total number of classes that get loaded.
In searching for a way around this I found java.beans.EventHandler's create method. This method (there are a few variations of it) its suppose to provide a one liner to create anonymous implementations of listener interfaces (like JavaFX's EventHandler). So I decided to try it out against some of the sample JavaFX code that is out there.
I used.... http://docs.oracle.com/javafx/2.0/events/KeyboardExample.java.htm... as my test code.
I replaced...
        private void installEventHandler(final Node keyNode) {
            // handler for enter key press / release events, other keys are
            // handled by the parent (keyboard) node handler
            final EventHandler keyEventHandler = new EventHandler<KeyEvent>() {
                @Override
                public void handle(final KeyEvent keyEvent) {
                    if (keyEvent.getCode() == KeyCode.ENTER) {
                        setPressed(keyEvent.getEventType() == KeyEvent.KEY_PRESSED);
                        keyEvent.consume();
            keyNode.setOnKeyPressed(keyEventHandler);
            keyNode.setOnKeyReleased(keyEventHandler);
        }with....
        private void installEventHandler(final Node keyNode) {
            // handler for enter key press / release events, other keys are
            // handled by the parent (keyboard) node handler
            final EventHandler keyEventHandler = (EventHandler)java.beans.EventHandler.create(EventHandler.class, this, "handle", "");
            keyNode.setOnKeyPressed(keyEventHandler);
            keyNode.setOnKeyReleased(keyEventHandler);
public void handle(final KeyEvent keyEvent) {
            if (keyEvent.getCode() == KeyCode.ENTER) {
                setPressed(keyEvent.getEventType() == KeyEvent.KEY_PRESSED);
                keyEvent.consume();
        }It worked. The new code behaved just like the old code.
One caveat though. The class count did in fact go up by about 20 classes. I ran multiple runs and this was true for all of them. But I only applied this technique on one anonymous class. It could be the case that the real savings in class count come after many instances of swapping out anonymous classes with this technique.
From the javadoc
"Also, using EventHandler in large applications in which the same interface is implemented many times can reduce the disk and memory footprint of the application.
The reason that listeners created with EventHandler have such a small footprint is that the Proxy class, on which the EventHandler relies, shares implementations of identical interfaces. For example, if you use the EventHandler create methods to make all the ActionListeners in an application, all the action listeners will be instances of a single class (one created by the Proxy class). In general, listeners based on the Proxy class require one listener class to be created per listener type (interface), whereas the inner class approach requires one class to be created per listener (object that implements the interface)."
Edited by: jmart on Apr 23, 2012 2:13 AM

Well, the idea is that with Java 8 they can be rewritten to something like this:
private void installEventHandler(final Node keyNode) {
            // handler for enter key press / release events, other keys are
            // handled by the parent (keyboard) node handler
            EventHandler keyEventHandler = keyEvent => {
                    if (keyEvent.getCode() == KeyCode.ENTER) {
                        setPressed(keyEvent.getEventType() == KeyEvent.KEY_PRESSED);
                        keyEvent.consume();
            keyNode.setOnKeyPressed(keyEventHandler);
            keyNode.setOnKeyReleased(keyEventHandler);
        }Basically what you are doing now is sacrificing performance (both in real performance and in a lot of extra garbage created) for a little bit of memory gain. Unless you have good reasons and measurements to back this up I think this would definitely qualify as premature optimization.
I'm a heavy user of anonymous inner classes myself, having several hundreds of them now in my project and I have yet to run into problems. I often write code like the example below purely for readability and convience:
Set<String> someSet = new HashSet<>() {{
add("A");
add("B");
new HBox() {{
getChildren.add(new VBox() {{
    getChildren.add(new Label("Hi"));
getChildren.add(new VBox() {{
    getChildren.add(new Label("There"));
}};

I can't work with java Beans in IWS6

I have been trying to get my iWS6 to run java bean but has not been able to do so. I tried a few beans and I get the same message on the log:
[27/May/2002:18:30:50] info ( 3160): JSP: JSP1x compiler threw exception
org.apache.jasper.JasperException: Unable to compile class for JSP/local/iplanet/https-hdesk-1/config/../ClassCache/_jsps/_otro_jsp.java:60: Class _jsps.UserData not found.
UserData user = null;
^
/local/iplanet/https-hdesk-1/config/../ClassCache/_jsps/_otro_jsp.java:63: Class _jsps.UserData not found.
user= (UserData)
^
/local/iplanet/https-hdesk-1/config/../ClassCache/_jsps/_otro_jsp.java:68: Class _jsps.UserData not found.
user = (UserData) Beans.instantiate(this.getClass().getClassLoader(), "UserData");
^
3 errors
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:284)
at com.iplanet.server.http.servlet.NSServletEntity.load(NSServletEntity.java:252)
at com.iplanet.server.http.servlet.NSServletEntity.update(NSServletEntity.java:173)
at com.iplanet.server.http.servlet.NSServletRunner.Service(NSServletRunner.java:416)
[27/May/2002:18:30:50] warning ( 3160): Internal error: Failed to get GenericServlet. (uri=/otro.jsp,SCRIPT_NAME=/otro.jsp)
I read a similar answer in this Forum but I couldn't find good results.
I'm using Solaris SPARC and JDK 1.3. When I run the Web server I Find these messages:
Java VM classpath: /local/iplanet/plugins/servlets/examples/legacy/beans.10/SDKBeans10.jar:/local/iplanet/docs:/local/iplanet/bin/https/jar/NSServletLayer.jar:/local/iplanet/bin/https/jar/NSJavaUtil.jar:/local/iplanet/bin/https/jar/NSJavaMiscUtil.jar:/local/iplanet/bin/https/jar/servlet.jar:/local/iplanet/bin/https/jar/servlet-2.3-filters-api.jar:/local/iplanet/bin/https/jar/jsp092.jar:/local/iplanet/bin/https/jar/jaxp.jar:/local/iplanet/bin/https/jar/crimson.jar:/local/iplanet/bin/https/jar/xalan.jar:/local/iplanet/bin/https/jar/jspengine.jar:
[27/May/2002:18:29:21] info ( 3160): Loading IWSSessionManager by default.
[27/May/2002:18:29:21] info ( 3160): IWSSessionManager: Maximum number of sessions is 1000
[27/May/2002:18:29:23] info ( 3160): Successfully initialized web application environment (web-apps.xml) for virtual server (https-hdesk-1)
[27/May/2002:18:29:23] warning ( 3160): The server configuration may require more file descriptors than the operating system provides. If you encounter PR_PROC_DESC_TABLE_FULL_ERROR errors, you may wish to increase the operating system hard file descriptor limit from 1024 to 5763 (see your operating system documentation) or decrease one or more of the following settings: MaxFiles in nsfc.conf and ConnQueueSize, RqThrottle, and MaxKeepAliveConnections in magnus.conf.
[27/May/2002:18:30:46] info ( 3160): Internal Info: loading servlet /otro.jsp
I've run many jsp files without problem, but when I use java Beans it doesn't work.
Thank you
P.D. The Classpath already contains the Java Bean file.

Hola Daniel,
Make this simple thing, import the class in your jsp, for example, in your case this should be:
<%@ page import="UserData" %>
The jasper compiler assumes that any unqualified class is part of the package jsps. I think this is to allow class definitions in the jsps. So if you indicate that the class is not packaged in jsps it will be found.
Juan

What makes a Java Bean invaild for a model import?

I'm busy prototyping some functionality that will expose some MDM 5.5 data through a WebDynpro application. I'm having a problem creating a java bean that will sit in front of an EJB, in that the Bean importer will refuse to import a bean if a certain line of code in a method is visible. Here's the offending code from the method:
try {
     A2iResultSet rs = cat.GetRecordsByValue(ary, rsd, Schema.MyTable.NAME);
     setEventLocation(rs.GetValueAt(0, Schema.MyTable.EVENT_LOCATION).GetStringValue());
} catch (StringException e) {
     setEventLocation("failed to find record");
Note that I have a class instance variable called 'eventLocation', which has get/set methods defined for it, thereby satisfying the Javabean requirement.
The first two lines of the 'try' block are the problem. If I comment them out and assemble the DC, I can import the Bean into a model with no issues. If I uncomment them, I cannot import the bean - I get a message that says 'Invalid Jar - no beans to import'.
Can someone explain why this is happening? Does it have something to do with the StringException? As far as I can tell from the Java bean model import documentation, I think I'm doing everything correctly, but something must be amiss.
Suggestions?

Pablo,
Now I understand your question in comments to my blog better
You have to add "ejb20" classes to your WebDynpro project as well, and import model afterwards.
In WebDynpro DC expand path (<project> -> DC MetData -> DC Definition -> Used DC) and invoke "Add Used DC..." in contextual menu. In dialog select "<dev. config> -> SAP-J2EE -> ejb20 -> DC MetaData -> Public Parts -> default". Set dependencies Built-time (probably Design-time as well). Click OK. Try to import model. If fails, restart IDE and try to import again.
Valery Silaev
EPAM Systems
http://www.NetWeaverTeam.com/

Java Bean object in Developer 6

Hi
When i create a java bean object in developer 6.0 the object is
not visiable in the canvas, but the object is created in the
object navigator. Can some one give a solution to this.
bye
sanjay
null

Dear,
Your path & class_path has not been set in the control panel.
Go to system, then environment set your required path. It will
work.
Adil
Sanjay Subramanyam (guest) wrote:
: Hi
: When i create a java bean object in developer 6.0 the object
is
: not visiable in the canvas, but the object is created in the
: object navigator. Can some one give a solution to this.
: bye
: sanjay
null

Java Beans requirement

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