How to exchange information(parameters) between servlets & jsps

with an examle if possible.

Hi
Exchanging parameters/objects between JSP and Servlets is done by creating an Object and placing it in the ServletContext , User Session or the Request depending on whether the Object requires Application Wide scope, Session Scope or Request Scope respectively.
If the object is created in the Servlet then it can shared by placing it in either Context, Session or Request through the setAttribute method and similarly retrieved through the getAttribute method.
For JSP use the <jsp:useBean> tag to retrieve/create the Object (bean).
For eaxmples see the following Links:
http://java.sun.com/docs/books/tutorial/servlets/communication/attributes.html
http://developer.java.sun.com/developer/onlineTraining/JSPIntro/contents.html#JSPIntro11
Good Luck!
Eshwar Rao
Developer Technical Support
Sun microsystems
http://www.sun.com/developers/support

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Crypt & decrypt parameters between servlets

Hi,
I am developing a web application and I would like to know how to crypt the parameters
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First, POST is not a solution. Just because its not in the URL doesn't mean a user can't get at them. If it was just cosmetic (he wanted a clean URL) then POST would be okay. He wants things encrypted, so I assume that he doesn't want people to know what the values are.
There are a couple of possible solutions. One requires server side storage overhead.
1) Map the actual values to dummy values before you write the page. Create a HashMap, store the key id in the HashMap with a randomly generated key. Use the randomly generated key in the URL.
String keyid = "realkeyid";
HashMap map = new HashMap();
String randkey = Integer.toString(Random.nextInt());
map.add(randkey, keyid);
session.setAttribute("map", map);
//--- Now use the randkey value on your web page URL
When the next request comes in, take the key in the URL, get the HashMap from the session and use the key to get the real keyid.
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long cryptKey = Long.longValue((Long) session.getAttribute("cryptkey"));
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Considerations:
Option 1 will not work for large data sets. You would have to store too much information in the session incurring memory overhead. This the more secure of the two though as the actual data never gets to the client.
Option 2 is much less secure but very lightweight. You can use any cipher you wish. The more often you change the key, the more secure this option is. Changing a key with every request is best.
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Hello all
First of all, my apologies for my English. This is the first time writing to forum.
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See the J2EE API:
http://java.sun.com/javaee/5/docs/api/

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im trying to do this but i could not find any way for this.
can any one help me how can i pass parameters between two forms
in forms4.5. any help will be appreciated
thanks.
null

Global variables can be used, but you can do what the online help
says ...
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list. A parameter list is a named programmatic construct that is
simply a list of parameter names (called keys) and their values.
You can pass parameter values to forms invoked by the built-in
subprograms CALL_FORM, OPEN_FORM, and NEW_FORM. In addition, you
can pass parameter values to other Oracle tools with the
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n a user-defined form parameter defined in a form invoked
by the CALL_FORM, OPEN_FORM, or NEW_FORM built-in subprograms
n a command line or user-defined parameter for a product
invoked with the RUN_PRODUCT built-in subprogram
Data Parameters The value of a data parameter being passed to a
called product is always the name of a record group defined in
the current form. (A record group is a data structure that
stores records derived from a query or through programmatic
assignment.) Data parameters are used to pass data to products
invoked with the RUN_PRODUCT built-in subprogram. You cannot
pass data parameters to forms.
The following table shows the structure of a parameter list that
contains four parameters:
Key Paramtype Value
CITY Text_Parameter 'BOGOTA'
CATEGORY Text_Parameter 'EXPORTS'
MULTIPLIER Text_Parameter '.0275'
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arun reddy (guest) wrote:
: im trying to do this but i could not find any way for this.
: can any one help me how can i pass parameters between two forms
: in forms4.5. any help will be appreciated
: thanks.
null

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Parameters are passed to called forms by means of a parameter
list. A parameter list is a named programmatic construct that is
simply a list of parameter names (called keys) and their values.
You can pass parameter values to forms invoked by the built-in
subprograms CALL_FORM, OPEN_FORM, and NEW_FORM. In addition, you
can pass parameter values to other Oracle tools with the
RUN_PRODUCT procedure.
A parameter you include in a parameter list can be either a text
parameter or a data parameter. The parameter type determines how
its value is interpreted.
Text Parameters The value of a text parameter being passed to a
called product is a CHAR string that can represent the following:
n a user-defined form parameter defined in a form invoked
by the CALL_FORM, OPEN_FORM, or NEW_FORM built-in subprograms
n a command line or user-defined parameter for a product
invoked with the RUN_PRODUCT built-in subprogram
Data Parameters The value of a data parameter being passed to a
called product is always the name of a record group defined in
the current form. (A record group is a data structure that
stores records derived from a query or through programmatic
assignment.) Data parameters are used to pass data to products
invoked with the RUN_PRODUCT built-in subprogram. You cannot
pass data parameters to forms.
The following table shows the structure of a parameter list that
contains four parameters:
Key Paramtype Value
CITY Text_Parameter 'BOGOTA'
CATEGORY Text_Parameter 'EXPORTS'
MULTIPLIER Text_Parameter '.0275'
NEW_DATA Data_Parameter 'RECORD_GROUP8'
arun reddy (guest) wrote:
: im trying to do this but i could not find any way for this.
: can any one help me how can i pass parameters between two forms
: in forms4.5. any help will be appreciated
: thanks.
null

Transfering data between servlets

hi
how would i transfer data between servlets - Im creating a form (form1) which asks the user to enter information - the user then submits, and this takes them to the next form (form2) - i need to transfer the data from form1 to form2 (ie. name, lastname). code follows
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Have you tryed using the request parameter? It should contain what you seek, I think.
Here for example;
String firstName = request.getParameter("name");
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Passing parameters between JSP and Servlet

The scenario is as follows:
There is a JSP page that sends a string as a hidden parameter to a servlet:
<input type="hidden" name=<%= Book.NAME %> value=<%= book.getName() %> >
In the servlet there is a print statement that checks the parameter value:
System.out.println("Book name: "+request.getParameter(Book.NAME));
The problem is as follows: if the name of the book consists of more than one word
such as "Servlets and JSP", the print statement will print only Servlet.
If the JSP page passes a string directly as shown here:
<input type="hidden" name="Test" value="Test String" >
The servlet will print the complete string: Test String
The same problem appears if the string is passed between two JSP pages.
Any help is greatly appreciated.
Regards,
Basil Mahdi

You might want to try
<input type="hidden" name="<%= Book.NAME %>" value="<%=URLEncode.encode(book.getName(), "UTF-8")%>" >This will take care of any wierd un-url friendly charcters that might appear in the book titles such as the ' or " which may be the problem.

How can pass information between 2 par file in iView???

Hello,using PDK i've have created an iview calling 2 .par file, the first par file contains a menu that the user selects a products and then when press load button generates a table with information. The table with information is generated in second .par file, that collects the information passed by the menu (through beans) and with a BAPI generates the table. I made it because the menu must be separated in one frame, and the table in other...(and the first frame must displace, how a html frame)
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I'm using jsp,HTMLB .
Thanks.

Hi,
try to have a look to the docs contained in this zip file.
They explain how to implement a portal component, a portal service and how to implement comunication between portal components, using POM and other features.
Maybe could be a good starting point for you
the file is
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/com.sapportals.km.docs/documents/a1-8-4/component and service creation tutorial.zip
Ciao
Roberto

How to implement Servlet/JSP in PAR to be used standalone (not as iView)

Hi everyone!
I want to develop a Servlet (or a JSP) that is part of my PAR with the main iView because it will be called in an iframe within that iView.
1. It has to be possible to call it directly from the Browser (iframe).
2. The output has to be exactly what i generate in it, meaning there must not be added anything to the output by the portal.
3. Because it uses the same classes that the iView itself is made of, I think it has to be part of the same PAR file.
4. Creating the servlet in an EAR and then copying (duplicating) the class files from the iView into it or putting them into their own jar and copying that into the PAR and the EAR is not really an option (for maintenance and development reasons)
What I tried so far:
-- implement the functions in a JSP which I put into dist/jsp => JSP is accessible from the browser but importing classes from the src.core is not possible (neither from default package, nor from any other named package in there)
-- implement in a JSP which I put into dist/PORTAL_INF/pagelet => JSP is not accessible from the browser (tried with the URL from IResourceInformation), so I don't know whether the imports would work
-- implement in a Servlet class in the src.core => don't know how to access that from the browser or how to configure it to be accessible or if this is possible at all
Maybe I am looking at the whole thing from the wrong side and the solution is something completely different from what I thought.
I have looked for information on this for nearly 8 hours now but did not find anything that really helped me. So any help is really appreciated.
Kind regards, Roland

First, thanks for the links.
But
3. Put the compiled servlet class in the private lib or classes folder.
seems not very pratical to me as you always have an additional manual step to do after each and every little change and therefore another source for possible errors. Also you have to switch perspectives in Developer Studio to do the copying. Isn't there a way to use the already existing class files from the iView?
Another question away from that: How do I access such a servlet via the web browser? What is the URL to it?
Quite trivial, but didn't find information on that, too.
Thanks anyway, Roland

How to exchange information(parameters) between servlets & jsps

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