Good extended math + utility class

It has proved surprisingly difficult to find a free "extended" math class for java - all I'm after is a utility class with things like erf, cosh, sinh... things that java.lang.Math lacks.
I must be doing something wrong, but if some altruistic person could point me in the right direction, I'd be grateful. :)

this might be even more useless to you, hehe. but you can have a look anyway:
http://www.jiefei.pwp.blueyonder.co.uk/Computing/Coursework/GraphicCalculator/docs/index.html

Similar Messages

Extending Math class

As I understand, in actionscript 2 you could extend flash's Math class to add your own functions, but this is no longer possible in actionscript 3. I want to add a mod() function to the Math class, and I'm assuming I have to write a wrapper class to accomplish this. How do I import the existing Math class into my MathPlus or whatever class? Also, is there anything else I should know about this?

Thanks for the replies (very good to know about %). The only reason I would prefer to extend Math or build a wrapper around it is if I were to write a sufficient number of additions such that trying to remember which were in Math and which were in my custom class became difficult. I just think it would be nice to have access to all of my (and Flash's) math related code within one class.
It just occurs to me that I just need to make functions in my class that call the ones in Math.

Extending java.util.EventObject to create user defined Events

Dear All,
Can someone point me to a decent tutorial/article/example that explains how and when to extend java.util.EventObject class to create my own EventObject and Event mechanism.
Please not the waterEvent, pipe and source example from the java beans tutorial :))
regards
Rupinder

??

Util class to extract Data from Data base Table.

Is there any Util class to extract all records from Data base table into DAT file.For example(get all amployees from EMPLOYEE table in to employee.DAT )

What is a DAT file?
Anyway, this can be achieved using a shot of JDBC [1] and some business logic [2] to populate/group/concat the data together in a DAT format and writing [3] it to that DAT file.
[1] JDBC tutorial: http://www.google.com/search?q=jdbc+tutorial+site:sun.com
[2] Use your brains and things you ever learnt in maths and basic Java tutorials/books.
[3] I/O tutorial: http://www.google.com/search?q=io+tutorial+site:sun.com

Compiling a servlet with utility class

Hello,
I am having trouble compiling a servlet that uses a utility class.
The compiler doesn't seem to recognize the utility class for some reason.
my classpath is set to:
.;C:\ServletDevel;C:\Program Files\Apache Software Foundation\common\lib\servlet-api.jar
the error:
Cannot find symbol: ServletUtilities
the servlet code:
package coreservlets;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
/** test the use of packages and utilities on the server */
public class helloservlet3 extends HttpServlet {
public void doGet(HttpServletRequest request,
               HttpServletResponse response)
               throws ServletException, IOException {
     response.setContentType("text/html");
     PrintWriter out = response.getWriter();
     String title = "Hello (3)";
     out.println(ServletUtilities.headWithTitle(title) +
          "<body bgcolor=\"#FDF5E6\">\n" +
          "<h1>" + title + "</h1>\n" +
          "</body></html>");
the utility class:
package coreservlets;
import javax.servlet.*;
import javax.servlet.http.*;
/** time saving static methods */
public class ServletUtilities {
     public final static String docType =
     "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 " +
     "Transitional//EN\">";
public static String headWithTitle(String title){
return (docType + "\n" + "<html>\n" +
          "<head><title>" + title + "</title></head>\n");
any help wouldbe greatly appreciated.

Nope still getting an error
helloservlet3.java:17:cannot find symbol
symbol : class ServletUtilities
location: package coreservlets
out.println(coreservlets.ServletUtilities.headWithTitle(title) +
thanks for the help, i'll keep on trying to figure it out.

Obtain CallerPrincipal in a utility class

Hi,
I'd like to obtain the caller principal of a ejb from a utility class. I know I can easily get the EJBContext inside the ejb itself using the callback from the container to the setSeccionCoontect method, but what if I need to knwo the caller principal in a utility class called by a business method of my ejb?
By the way, I'm using EJB2.1 in Weblogic 8.1 and I'm talking about SessionBeans. I know I could obtain the caller principal inside my ejb and simply pass it as a parameter to my utility class, but I dont liek to idea of adding a user parameter to my utility clases method.
I'm aware that I could do a InitialContext.lookup("java:/comp/EJBContext") if I was using a EJB3 container, but I cant find the equivalent with EJB2.
Thanks!

Every thread has a stack of its own and its own copies of local variables, if a static method uses only locals it doesn't have to be synchronized.
Using lazy initialization with the singleton pattern is a good example of side effects. Examine this code:class Singleton {
    static Singleton instance;
    static Singleton getInstance() {
        if (instance == null) instance = new Singleton();
        return instance;
    // don't allow other classes to create an instance
    private Singleton() {}
}Now what happens if two threads simultaneously enter the getInstance method and both find the value of the "instance" variable null in the if-condition? You end up creating an instance of the class twice, which is not what you want. This can be solved by writing the method declaration as "synchronized static Singleton getInstance()" so no two threads can enter the method simultaneously.

Extend the String Class

Is there a way to extend the string class? I know it's final, if i make my class final too would that work? I want to add some functionality to the string class, but I wanna be able to do concatination with the + operator and stuff like that. That's special to the String class.
Any help would be great.
Thanks.
Joe

Well, put your mind at easy with the fact that being
able to use the '+' operator on Strings is a design
flaw in Java. At least from a purist point of view...And from a pragmatist's point of view, it's a reasonable compromise, the benefit of which outweighs the downside. This is consistent with Java's goal as a good general-purpose language. It's not intended to be pure OO or pure anything else.

Trouble extending java.util.Arrays

I have written some utility functions for dealing with arrays and I would like to bundle them into a class along with java's built-in array functions (java.util.Arrays). To do this, I tried to extends the class java.util.Arrays like this:
public class ArrayUtils extends java.util.Arrays
/* some static methods */
When I try to compile this with javac (even with no class body between the braces), I get an error "error:Cannot find constructor "Arrays" with matching parameters [JLS 15.12]". Does anyone know what's going on here? Why is the compiler looking for a constructor? And why can't it find one? I would very much appreciate your insight. Thanks. Eli

Does anyone know what's
going on here? Why is the compiler looking for a
constructor? And why can't it find one?Conceputually....
Inheritance exists to allow one to inherit from an object. In java objects can be created by using a class. However classes in java do not have to be objects. And you are trying to inherit from something that is not an object.
One of the other uses for class in java is to group a number of convienent functions together. (Grouped functions do NOT represent a class.) That is what java.util.Arrays is.
Technically....
The class java.util.Arrays has a private constructor which means you can't derive anything from it.

RE: [iPlanet-JATO] Re: Use Of models in utility classes

Hi all,
if you add the following to your spider2jato.xml
It will automatically map your CSpDataObject.executeImmediate to use
ExecuteImmediateUtil.executeImmediateSelect with the arguments mapped as
well.
Kostas
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[CSpDataObject[.\s]*executeImmediate[\s]*$([^,]*),([^)]*)$]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[CSpDataObject[.\s]*executeImmediate[\s]*$([^,]*),([^)]*)$]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[ExecuteImmediateUtil.executeImmediateSelect($1,$2,
getRequestContext())]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
-----Original Message-----
From: Matthew Stevens
Cc: vnamboori@y...
Sent: 11/29/01 11:23 AM
Subject: RE: [iPlanet-JATO] Re: Use Of models in utility classes
Namburi,
I have included an example in the file ExecuteImmediateUtil.java
The Yahoo Group will not handle the attached file we will put it in the
Files section shortly.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100253094145066046167121181">vnamboori@y...</a>]
Sent: Thursday, November 29, 2001 12:29 PM
Subject: [iPlanet-JATO] Re: Use Of models in utility classes
Matt,
For CSpSelect.executeImmediate() I have an example of custom helpermethod as a replacement which uses JDBC results instead of
CSpDBResult.
Can you send me this example.
Thanks
Namburi
--- In iPlanet-JATO@y..., "Matthew Stevens" <matthew.stevens@E...>
wrote:
Namburi,
I will post a document to the group site this evening which has thedetails
on various tactics of migrating these type of utilities.Essentially, you
either need to convert these utilities to Models themselves or keepthe
utilities as is and simply use the
RequestManager.getRequestContext.getModelManager().getModel()
to statically access Models.
For CSpSelect.executeImmediate() I have an example of custom helpermethod
as a replacement whicch uses JDBC results instead of CSpDBResult.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100208071048">vnamboori@y...</a>]
Sent: Tuesday, August 07, 2001 3:24 PM
Subject: [iPlanet-JATO] Use Of models in utility classes
Hi All,
In the present ND project we have lots of utility classes. These
classes in diffrent directory. Not part of nd pages.
In these classes we access the dataobjects and do the
manipulations.
So we access dataobjects directly like
CSpider.getDataObject("do....");
and then execute it.
Since the migration tool does not do much of conversion for these
utilities we have to do manually.
My question is Can we access the the models in the post migration
sameway or do we need requestContext?
We have lots of utility classes which are DataObject intensive.Can
someone suggest a better way to migrate this kind of code.
Thanks
Namburi
[email protected]
For more information about JATO, please visit:
http://developer.iplanet.com/tech/appserver/framework/index.jsp
[Non-text portions of this message have been removed]
For more information about JATO, please visit:
http://developer.iplanet.com/tech/appserver/framework/index.jsp
[Non-text portions of this message have been removed]

Hi all,
if you add the following to your spider2jato.xml
It will automatically map your CSpDataObject.executeImmediate to use
ExecuteImmediateUtil.executeImmediateSelect with the arguments mapped as
well.
Kostas
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[CSpDataObject[.\s]*executeImmediate[\s]*$([^,]*),([^)]*)$]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[CSpDataObject[.\s]*executeImmediate[\s]*$([^,]*),([^)]*)$]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[ExecuteImmediateUtil.executeImmediateSelect($1,$2,
getRequestContext())]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
-----Original Message-----
From: Matthew Stevens
Cc: vnamboori@y...
Sent: 11/29/01 11:23 AM
Subject: RE: [iPlanet-JATO] Re: Use Of models in utility classes
Namburi,
I have included an example in the file ExecuteImmediateUtil.java
The Yahoo Group will not handle the attached file we will put it in the
Files section shortly.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100253094145066046167121181">vnamboori@y...</a>]
Sent: Thursday, November 29, 2001 12:29 PM
Subject: [iPlanet-JATO] Re: Use Of models in utility classes
Matt,
For CSpSelect.executeImmediate() I have an example of custom helpermethod as a replacement which uses JDBC results instead of
CSpDBResult.
Can you send me this example.
Thanks
Namburi
--- In iPlanet-JATO@y..., "Matthew Stevens" <matthew.stevens@E...>
wrote:
Namburi,
I will post a document to the group site this evening which has thedetails
on various tactics of migrating these type of utilities.Essentially, you
either need to convert these utilities to Models themselves or keepthe
utilities as is and simply use the
RequestManager.getRequestContext.getModelManager().getModel()
to statically access Models.
For CSpSelect.executeImmediate() I have an example of custom helpermethod
as a replacement whicch uses JDBC results instead of CSpDBResult.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100208071048">vnamboori@y...</a>]
Sent: Tuesday, August 07, 2001 3:24 PM
Subject: [iPlanet-JATO] Use Of models in utility classes
Hi All,
In the present ND project we have lots of utility classes. These
classes in diffrent directory. Not part of nd pages.
In these classes we access the dataobjects and do the
manipulations.
So we access dataobjects directly like
CSpider.getDataObject("do....");
and then execute it.
Since the migration tool does not do much of conversion for these
utilities we have to do manually.
My question is Can we access the the models in the post migration
sameway or do we need requestContext?
We have lots of utility classes which are DataObject intensive.Can
someone suggest a better way to migrate this kind of code.
Thanks
Namburi
[email protected]
For more information about JATO, please visit:
http://developer.iplanet.com/tech/appserver/framework/index.jsp
[Non-text portions of this message have been removed]
For more information about JATO, please visit:
http://developer.iplanet.com/tech/appserver/framework/index.jsp
[Non-text portions of this message have been removed]

Re: [iPlanet-JATO] Re: Use Of models in utility classes - Pease don't forget about the regular expression potential

Namburi,
When you said you used the Reg Exp tool, did you use it only as
preconfigured by the iMT migrate application wizard?
Because the default configuration of the regular expression tool will only
target the files in your ND project directories. If you wish to target
classes outside of the normal directory scope, you have to either modify the
"Source Directory" property OR create another instance of the regular
expression tool. See the "Tool" menu in the iMT to create additional tool
instances which can each be configured to target different sets of files
using different sets of rules.
Usually, I utilize 3 different sets of rules files on a given migration:
spider2jato.xml
these are the generic conversion rules (but includes the optimized rules for
ViewBean and Model based code, i.e. these rules do not utilize the
RequestManager since it is not needed for code running inside the ViewBean
or Model classes)
I run these rules against all files.
See the file download section of this forum for periodic updates to these
rules.
nonProjectFileRules.xml
these include rules that add the necessary
RequestManager.getRequestContext(). etc prefixes to many of the common
calls.
I run these rules against user module and any other classes that do not are
not ModuleServlet, ContainerView, or Model classes.
appXRules.xml
these rules include application specific changes that I discover while
working on the project. A common thing here is changing import statements
(since the migration tool moves ND project code into different jato
packaging structure, you sometime need to adjust imports in non-project
classes that previously imported ND project specific packages)
So you see, you are not limited to one set of rules at all. Just be careful
to keep track of your backups (the regexp tool provides several options in
its Expert Properties related to back up strategies).
----- Original Message -----
From: <vnamboori@y...>
Sent: Wednesday, August 08, 2001 6:08 AM
Subject: [iPlanet-JATO] Re: Use Of models in utility classes - Pease don't
forget about the regular expression potential
Thanks Matt, Mike, Todd
This is a great input for our migration. Though we used the existing
Regular Expression Mapping tool, we did not change this to meet our
own needs as mentioned by Mike.
We would certainly incorporate this to ease our migration.
Namburi
--- In iPlanet-JATO@y..., "Todd Fast" <toddwork@c...> wrote:
All--
Great response. By the way, the Regular Expression Tool uses thePerl5 RE
syntax as implemented by Apache OROMatcher. If you're doing lotsof these
sorts of migration changes manually, you should definitely buy theO'Reilly
book "Mastering Regular Expressions" and generate some rules toautomate the
conversion. Although they are definitely confusing at first,regular
expressions are fairly easy to understand with some documentation,and are
superbly effective at tackling this kind of migration task.
Todd
----- Original Message -----
From: "Mike Frisino" <Michael.Frisino@S...>
Sent: Tuesday, August 07, 2001 5:20 PM
Subject: Re: [iPlanet-JATO] Use Of models in utility classes -Pease don't
forget about the regular expression potential
Also, (and Matt's document may mention this)
Please bear in mind that this statement is not totally correct:
Since the migration tool does not do much of conversion for
these
utilities we have to do manually.Remember, the iMT is a SUITE of tools. There is the extractiontool, and
the translation tool, and the regular expression tool, and severalother
smaller tools (like the jar and compilation tools). It is correctto state
that the extraction and translation tools only significantlyconvert the
primary ND project objects (the pages, the data objects, and theproject
classes). The extraction and translation tools do minimumtranslation of the
User Module objects (i.e. they repackage the user module classes inthe new
jato module packages). It is correct that for all other utilityclasses
which are not formally part of the ND project, the extraction and
translation tools do not perform any migration.
However, the regular expression tool can "migrate" any arbitrary
file
(utility classes etc) to the degree that the regular expressionrules
correlate to the code present in the arbitrary file. So first andforemost,
if you have alot of spider code in your non-project classes youshould
consider using the regular expression tool and if warranted adding
additional rules to reduce the amount of manual adjustments thatneed to be
made. I can stress this enough. We can even help you write theregular
expression rules if you simply identify the code pattern you wish to
convert. Just because there is not already a regular expressionrule to
match your need does not mean it can't be written. We have notnearly
exhausted the possibilities.
For example if you say, we need to convert
CSpider.getDataObject("X");
To
RequestManager.getRequestContext().getModelManager().getModel(XModel.class);
Maybe we or somebody else in the list can help write that regularexpression if it has not already been written. For instance in thelast
updated spider2jato.xml file there is already aCSpider.getCommonPage("X")
rule:

<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[CSpider[.\s]*getPage[\s]*\(\"([^"]*)\"]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[CSpider[.\s]*getPage[\s]*\(\"([^"]*)\"]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[getViewBean($1ViewBean.class]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
Following this example a getDataObject to getModel would look
like this:
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[CSpider[.\s]*getDataObject[\s]*\(\"([^"]*)\"]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[CSpider[.\s]*getDataObject[\s]*\(\"([^"]*)\"]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[getModel($1Model.class]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
In fact, one migration developer already wrote that rule andsubmitted it
for inclusion in the basic set. I will post another upgrade to thebasic
regular expression rule set, look for a "file uploaded" posting.Also,
please consider contributing any additional generic rules that youhave
written for inclusion in the basic set.
Please not, that in some cases (Utility classes in particular)
the rule
application may be more effective as TWO sequention rules ratherthan one
monolithic rule. Again using the example above, it will convert
CSpider.getDataObject("Foo");
To
getModel(FooModel.class);
Now that is the most effective conversion for that code if that
code is in
a page or data object class file. But if that code is in a Utilityclass you
really want:
>
RequestManager.getRequestContext().getModelManager().getModel(FooModel.class
So to go from
getModel(FooModel.class);
To
RequestManager.getRequestContext().getModelManager().getModel(FooModel.class
You would apply a second rule AND you would ONLY run this rule
against
your utility classes so that you would not otherwise affect yourViewBean
and Model classes which are completely fine with the simplegetModel call.
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[getModel$]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[getModel\(]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[RequestManager.getRequestContext().getModelManager().getModel(]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
A similer rule can be applied to getSession and other CSpider APIcalls.
For instance here is the rule for converting getSession calls toleverage
the RequestManager.
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[getSession\($\.]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[getSession\.]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[RequestManager.getSession().]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
----- Original Message -----
From: "Matthew Stevens" <matthew.stevens@e...>
Sent: Tuesday, August 07, 2001 12:56 PM
Subject: RE: [iPlanet-JATO] Use Of models in utility classes
Namburi,
I will post a document to the group site this evening which has
the
details
on various tactics of migrating these type of utilities.
Essentially,
you
either need to convert these utilities to Models themselves or
keep the
utilities as is and simply use the
RequestManager.getRequestContext.getModelManager().getModel()
to statically access Models.
For CSpSelect.executeImmediate() I have an example of customhelper
method
as a replacement whicch uses JDBC results instead of
CSpDBResult.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100208071048">vnamboori@y...</a>]
Sent: Tuesday, August 07, 2001 3:24 PM
Subject: [iPlanet-JATO] Use Of models in utility classes
Hi All,
In the present ND project we have lots of utility classes.
These
classes in diffrent directory. Not part of nd pages.
In these classes we access the dataobjects and do themanipulations.
So we access dataobjects directly like
CSpider.getDataObject("do....");
and then execute it.
Since the migration tool does not do much of conversion forthese
utilities we have to do manually.
My question is Can we access the the models in the postmigration
sameway or do we need requestContext?
We have lots of utility classes which are DataObjectintensive. Can
someone suggest a better way to migrate this kind of code.
Thanks
Namburi
[email protected]
[email protected]
[Non-text portions of this message have been removed]
[email protected]
[email protected]

Namburi,
When you said you used the Reg Exp tool, did you use it only as
preconfigured by the iMT migrate application wizard?
Because the default configuration of the regular expression tool will only
target the files in your ND project directories. If you wish to target
classes outside of the normal directory scope, you have to either modify the
"Source Directory" property OR create another instance of the regular
expression tool. See the "Tool" menu in the iMT to create additional tool
instances which can each be configured to target different sets of files
using different sets of rules.
Usually, I utilize 3 different sets of rules files on a given migration:
spider2jato.xml
these are the generic conversion rules (but includes the optimized rules for
ViewBean and Model based code, i.e. these rules do not utilize the
RequestManager since it is not needed for code running inside the ViewBean
or Model classes)
I run these rules against all files.
See the file download section of this forum for periodic updates to these
rules.
nonProjectFileRules.xml
these include rules that add the necessary
RequestManager.getRequestContext(). etc prefixes to many of the common
calls.
I run these rules against user module and any other classes that do not are
not ModuleServlet, ContainerView, or Model classes.
appXRules.xml
these rules include application specific changes that I discover while
working on the project. A common thing here is changing import statements
(since the migration tool moves ND project code into different jato
packaging structure, you sometime need to adjust imports in non-project
classes that previously imported ND project specific packages)
So you see, you are not limited to one set of rules at all. Just be careful
to keep track of your backups (the regexp tool provides several options in
its Expert Properties related to back up strategies).
----- Original Message -----
From: <vnamboori@y...>
Sent: Wednesday, August 08, 2001 6:08 AM
Subject: [iPlanet-JATO] Re: Use Of models in utility classes - Pease don't
forget about the regular expression potential
Thanks Matt, Mike, Todd
This is a great input for our migration. Though we used the existing
Regular Expression Mapping tool, we did not change this to meet our
own needs as mentioned by Mike.
We would certainly incorporate this to ease our migration.
Namburi
--- In iPlanet-JATO@y..., "Todd Fast" <toddwork@c...> wrote:
All--
Great response. By the way, the Regular Expression Tool uses thePerl5 RE
syntax as implemented by Apache OROMatcher. If you're doing lotsof these
sorts of migration changes manually, you should definitely buy theO'Reilly
book "Mastering Regular Expressions" and generate some rules toautomate the
conversion. Although they are definitely confusing at first,regular
expressions are fairly easy to understand with some documentation,and are
superbly effective at tackling this kind of migration task.
Todd
----- Original Message -----
From: "Mike Frisino" <Michael.Frisino@S...>
Sent: Tuesday, August 07, 2001 5:20 PM
Subject: Re: [iPlanet-JATO] Use Of models in utility classes -Pease don't
forget about the regular expression potential
Also, (and Matt's document may mention this)
Please bear in mind that this statement is not totally correct:
Since the migration tool does not do much of conversion for
these
utilities we have to do manually.Remember, the iMT is a SUITE of tools. There is the extractiontool, and
the translation tool, and the regular expression tool, and severalother
smaller tools (like the jar and compilation tools). It is correctto state
that the extraction and translation tools only significantlyconvert the
primary ND project objects (the pages, the data objects, and theproject
classes). The extraction and translation tools do minimumtranslation of the
User Module objects (i.e. they repackage the user module classes inthe new
jato module packages). It is correct that for all other utilityclasses
which are not formally part of the ND project, the extraction and
translation tools do not perform any migration.
However, the regular expression tool can "migrate" any arbitrary
file
(utility classes etc) to the degree that the regular expressionrules
correlate to the code present in the arbitrary file. So first andforemost,
if you have alot of spider code in your non-project classes youshould
consider using the regular expression tool and if warranted adding
additional rules to reduce the amount of manual adjustments thatneed to be
made. I can stress this enough. We can even help you write theregular
expression rules if you simply identify the code pattern you wish to
convert. Just because there is not already a regular expressionrule to
match your need does not mean it can't be written. We have notnearly
exhausted the possibilities.
For example if you say, we need to convert
CSpider.getDataObject("X");
To
RequestManager.getRequestContext().getModelManager().getModel(XModel.class);
Maybe we or somebody else in the list can help write that regularexpression if it has not already been written. For instance in thelast
updated spider2jato.xml file there is already aCSpider.getCommonPage("X")
rule:

<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[CSpider[.\s]*getPage[\s]*\(\"([^"]*)\"]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[CSpider[.\s]*getPage[\s]*\(\"([^"]*)\"]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[getViewBean($1ViewBean.class]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
Following this example a getDataObject to getModel would look
like this:
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[CSpider[.\s]*getDataObject[\s]*\(\"([^"]*)\"]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[CSpider[.\s]*getDataObject[\s]*\(\"([^"]*)\"]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[getModel($1Model.class]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
In fact, one migration developer already wrote that rule andsubmitted it
for inclusion in the basic set. I will post another upgrade to thebasic
regular expression rule set, look for a "file uploaded" posting.Also,
please consider contributing any additional generic rules that youhave
written for inclusion in the basic set.
Please not, that in some cases (Utility classes in particular)
the rule
application may be more effective as TWO sequention rules ratherthan one
monolithic rule. Again using the example above, it will convert
CSpider.getDataObject("Foo");
To
getModel(FooModel.class);
Now that is the most effective conversion for that code if that
code is in
a page or data object class file. But if that code is in a Utilityclass you
really want:
>
RequestManager.getRequestContext().getModelManager().getModel(FooModel.class
So to go from
getModel(FooModel.class);
To
RequestManager.getRequestContext().getModelManager().getModel(FooModel.class
You would apply a second rule AND you would ONLY run this rule
against
your utility classes so that you would not otherwise affect yourViewBean
and Model classes which are completely fine with the simplegetModel call.
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[getModel$]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[getModel\(]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[RequestManager.getRequestContext().getModelManager().getModel(]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
A similer rule can be applied to getSession and other CSpider APIcalls.
For instance here is the rule for converting getSession calls toleverage
the RequestManager.
<mapping-rule>
<mapping-rule-primarymatch>
<![CDATA[getSession\($\.]]>
</mapping-rule-primarymatch>
<mapping-rule-replacement>
<mapping-rule-match>
<![CDATA[getSession\.]]>
</mapping-rule-match>
<mapping-rule-substitute>
<![CDATA[RequestManager.getSession().]]>
</mapping-rule-substitute>
</mapping-rule-replacement>
</mapping-rule>
----- Original Message -----
From: "Matthew Stevens" <matthew.stevens@e...>
Sent: Tuesday, August 07, 2001 12:56 PM
Subject: RE: [iPlanet-JATO] Use Of models in utility classes
Namburi,
I will post a document to the group site this evening which has
the
details
on various tactics of migrating these type of utilities.
Essentially,
you
either need to convert these utilities to Models themselves or
keep the
utilities as is and simply use the
RequestManager.getRequestContext.getModelManager().getModel()
to statically access Models.
For CSpSelect.executeImmediate() I have an example of customhelper
method
as a replacement whicch uses JDBC results instead of
CSpDBResult.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100208071048">vnamboori@y...</a>]
Sent: Tuesday, August 07, 2001 3:24 PM
Subject: [iPlanet-JATO] Use Of models in utility classes
Hi All,
In the present ND project we have lots of utility classes.
These
classes in diffrent directory. Not part of nd pages.
In these classes we access the dataobjects and do themanipulations.
So we access dataobjects directly like
CSpider.getDataObject("do....");
and then execute it.
Since the migration tool does not do much of conversion forthese
utilities we have to do manually.
My question is Can we access the the models in the postmigration
sameway or do we need requestContext?
We have lots of utility classes which are DataObjectintensive. Can
someone suggest a better way to migrate this kind of code.
Thanks
Namburi
[email protected]
[email protected]
[Non-text portions of this message have been removed]
[email protected]
[email protected]

Re: [iPlanet-JATO] Use Of models in utility classes

Hi Matt,
Sounds like some of the stuff we need to migrate has a lot in common with
Namburi's project.
I would be very keen to get hold of a copy of the 'tactic' document you
mention below, as well as the sample code you mention to replace CspDBResult
stuff with JDBC results.
Thanks in advance,
Phil
----- Original Message -----
From: Matthew Stevens <matthew.stevens@E...>
Sent: Wednesday, August 08, 2001 7:56 AM
Subject: RE: [iPlanet-JATO] Use Of models in utility classes
Namburi,
I will post a document to the group site this evening which has thedetails
on various tactics of migrating these type of utilities. Essentially, you
either need to convert these utilities to Models themselves or keep the
utilities as is and simply use the
RequestManager.getRequestContext.getModelManager().getModel()
to statically access Models.
For CSpSelect.executeImmediate() I have an example of custom helper method
as a replacement whicch uses JDBC results instead of CSpDBResult.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100253094145066046167121181">vnamboori@y...</a>]
Sent: Tuesday, August 07, 2001 3:24 PM
Subject: [iPlanet-JATO] Use Of models in utility classes
Hi All,
In the present ND project we have lots of utility classes. These
classes in diffrent directory. Not part of nd pages.
In these classes we access the dataobjects and do the manipulations.
So we access dataobjects directly like
CSpider.getDataObject("do....");
and then execute it.
Since the migration tool does not do much of conversion for these
utilities we have to do manually.
My question is Can we access the the models in the post migration
sameway or do we need requestContext?
We have lots of utility classes which are DataObject intensive. Can
someone suggest a better way to migrate this kind of code.
Thanks
Namburi
[email protected]
[email protected]

Hi Matt,
Sounds like some of the stuff we need to migrate has a lot in common with
Namburi's project.
I would be very keen to get hold of a copy of the 'tactic' document you
mention below, as well as the sample code you mention to replace CspDBResult
stuff with JDBC results.
Thanks in advance,
Phil
----- Original Message -----
From: Matthew Stevens <matthew.stevens@E...>
Sent: Wednesday, August 08, 2001 7:56 AM
Subject: RE: [iPlanet-JATO] Use Of models in utility classes
Namburi,
I will post a document to the group site this evening which has thedetails
on various tactics of migrating these type of utilities. Essentially, you
either need to convert these utilities to Models themselves or keep the
utilities as is and simply use the
RequestManager.getRequestContext.getModelManager().getModel()
to statically access Models.
For CSpSelect.executeImmediate() I have an example of custom helper method
as a replacement whicch uses JDBC results instead of CSpDBResult.
matt
-----Original Message-----
From: vnamboori@y... [mailto:<a href="/group/SunONE-JATO/post?protectID=081071113213093190112061186248100253094145066046167121181">vnamboori@y...</a>]
Sent: Tuesday, August 07, 2001 3:24 PM
Subject: [iPlanet-JATO] Use Of models in utility classes
Hi All,
In the present ND project we have lots of utility classes. These
classes in diffrent directory. Not part of nd pages.
In these classes we access the dataobjects and do the manipulations.
So we access dataobjects directly like
CSpider.getDataObject("do....");
and then execute it.
Since the migration tool does not do much of conversion for these
utilities we have to do manually.
My question is Can we access the the models in the post migration
sameway or do we need requestContext?
We have lots of utility classes which are DataObject intensive. Can
someone suggest a better way to migrate this kind of code.
Thanks
Namburi
[email protected]
[email protected]

Is there a Java utility class to help with data management in a desktop UI?

Is there a Java utility class to help with data management in a desktop UI?
I am writing a UI to configure a network device that will be connected to the serial port of the computer while it is being configured. There is no web server or database for my application. The UI has a large number of fields (50+) spread across 16 tabs. I will write the UI in Java FX. It should run inside the browser when launched, and issue commands to the network device through the serial port. A UI has several input fields spread across tabs and one single Submit button. If a field is edited, and the submit button clicked, it issues a command and sends the new datum to the device, retrieves current value and any errors. so if input field has bad data, it is indicated for example, the field has a red border.
Is there a standard design pattern or Java utility class to accomplish the frequently encountered, 'generic' parts of this scenario? lazy loading, submitting only what fields changed, displaying what fields have errors etc. (I dont want to reinvent the wheel if it is already there). Otherwise I can write such a class and share it back here if it is useful.
someone recommended JGoodies Bindings for Swing - will this work well and in FX?

Many thanks for the reply.
In the servlet create an Arraylist and in th efor
loop put the insances of the csqabean in this
ArrayList. Exit the for loop and then add the
ArrayList as an attribute to the session.I am making the use of Vector and did the same thing as u mentioned.I am using scriplets...
>
In the jsp retrieve the array list from the session
and in a for loop step through the ArrayList
retrieving each CourseSectionQABean and displaying.
You can do this in a scriptlet but should also check
out the jstl tags.I am able to remove this problem.Thanks again for the suggestion.
AS

Extending a nested class and parent access

I want the child of the abstract inner class to have access to the inner classes parent's variables. I know that an inner class can access it's parent's variables and methods with the "[ParentClass].this.[var/method]" syntax. What's the appropriate syntax for the situation I'm describing?
My setup is like this:
class Canister {
int a = 0;
public abstract class Behavior
class Lonely Behavior extends Behavior
public int getParentVariable() {
return Canister.this.a;
}Thanks!
-stephen

The correction to my code is:
class Canister
int a = 0;
public abstract class Behavior
class LonelyBehavior extends Canister.Behavior
public int getParentVariable() {
return Canister.this.a;
}The compiler doesn't have a problem with me extending Canister.Behavior because it's public inside of Canister. But as I explained, the "[ParentClass].this.[var/method]" syntax doesn't work.
This is inconsistent with inheritance: you'd think that if you extend an inner class, you would inherit the abilities and characteristics of that inner class, just as you would in other cases of inheritance. It's also inconvenient: if the inner class is abstract because you want programmers to extend and upgrade it, those programmers have to change the source code of the enclosing class to include the new classes.
Anyway, thanks for the info.

EXTENDING the string class

ok, i know extending the string class is illegal because it's final, but i want to make an advanced string class that basically "extends" the string class and i've seen online this can be done through wrapper classes and/or composition, but i'm lost
here is my sample code that is coming up with numerous compile time errors due to the fact that when i declare a new AdvString object, it doesn't inherit the basic string features (note: Add is a method that can add a character to a specified location in a string)
class AdvString
     private String s;
     public AdvString(String s)
          this.s = s;
     public void Add(int pos, char ch)
          int this_len = (this.length()) + 1;
          int i;
          for(i=0;i<(this_len);i++)
               if(pos == i)
                    this = this + ch;
               else if(pos < i)
                    this = this + this.charAt(i-1);
               else
                    this = this + this.charAt(i);
     public static void main(String[] args)
          AdvString s1;
          s1 = new AdvString("hello");
          char c = 'x';
          int i = 3;
          s1.Add(i,c);
          //s2 = Add(s1,i,c);
          //String s2_reversed = Reverse(s2);
          System.out.println("s1 is: " + s1);
any tips?

see REString at,
http://www.geocities.com/rmlchan/mt.html
you will have to replicate all the String methods you are interested in, and just forward it to the String instance stored in REString or the like. it is like a conduit class and just passes most processing to the 'real' string. maybe a facade pattern.

Can an abstract class extend another abstract class?

Is it possible for an abstract class to extend another abstract class?
Say
public abstract class AComponent extends JComponent {
Thanks.

Yes

Good extended math + utility class

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