Good tutorials explain use of classes

good tutorials explain use of classes, and why do we use static in variable and method... why some variable are private, protected..
any good link to recommend?
as many as possible......
keep posting to let me read up..
i had read the java sun tutorial..

http://www.google.com/search?as_q=java+tutorial&num=100&hl=en&ie=ISO-8859-1&btnG=Google+Search&as_epq=&as_oq=&as_eq=&lr=lang_en&as_ft=i&as_filetype=&as_qdr=all&as_occt=title&as_dt=i&as_sitesearch=&safe=images
7,750 links to "Java Tutorial"

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Any good tutorials for using jQuery and ColdFusion to build mobile apps

Does anyone know of any good tutorials for using jQuery and ColdFusion to build mobile apps?
Thanks!
Lee

I was just this moment looking at this website http://jquerymobile.com/
Then for you a Google search on Jquerymobile and coldfusion
http://www.google.co.uk/search?q=jquerymobile+and+coldfusion&ie=utf-8&oe=utf-8&aq=t&rls=or g.mozilla:en-GB:official&client=firefox-a
http://jquerymobile.com/resources/
Brings me onto this tutorial
http://www.raymondcamden.com/index.cfm/2011/8/26/Making-jQuery-Mobile-templates-even-easie r--with-ColdFusion

Recommended tutorials for using paths/vector art in Photoshop?

Hi all!
Can you recommend any good tutorials for using paths/vector art in Photoshop?
Honestly, I've had a good look for even one - without much success.
I Have lots of experience with paths/vector art in Illustrator, Fireworks and InDesign but I believe you really can do great things with them in Photoshop now for illustration work.
i'm just baffled by it. I can fill and stroke and edit a vector shape in PS - but if I custom DRAW a vector path or shape, things get confusing!
Hoping someone can point me in a helpful direction
John

John,
I wouldn't claim to know everything there is to know, but I'm reasonably certain it hasn't changed.
Are the 'shapes' just vector masks with a raster element inside?
Yes. That's an accurate enough description.
And if you apply a colour to a path that you've drawn - does it rasterise?
It doesn't have to rasterize. If you see color, it's pixels.
I was definitely of the impression that a lot more could be done in PS these days that might formerly have been done in ILLUSTRATOR.
The shape/path tools in Photoshop have been enhanced and improved in recent years, but the product of their use still differs from Illustrator's true vector output.

Can some recommend a good tutorials on how to use timers

I would love a good tutorial on counters to know how they work I am practising using my USB DAQPad-6015, but will implement the solution and would like to get a better understanding before I start

Hi
I find the following diagram really good for explaining counters:
Count Register
The count register stores the current count of the counter. The count register can be queried with software.
Source
The source is an input signal that can change the current count stored in the count register. The counter looks for either rising or falling edges on the source signal. Whether a rising or falling edge changes the count is software selectable. The type of edge (rising or falling) that is selected is referred to as the active edge of the signal. When an active edge is received on the source signal the count will change. Whether an active edge increments or decrements the current count is also software selectable.
Gate
The gate is an input signal that decides if an active edge on the source will change the count. Counting can occur when the gate is high, low, or between various combinations of rising and falling edges. Gate settings are made in software. The gate is similar to a line mask in digital I/O, because it allows you to either acknowledge or ignore active edges on the source.
Out
The out is an output signal used to generate pulses or a series of pulses often referred to as a pulse train. The output signal is TTL compatible.
The Source and Gate signals can be input on any of the PFI lines but there are default pins assigned which are specified in the DAQ assistant when you set up a counter task, you can also find that information on the pinout for the device.
The source and gate can be used in different configurations for multiple applications. I need to have a look at your code but from my initial glance it looks like it's setting up a retriggerable pulse train.
I'll find some more resources and post back with an explanation of how that type of counter application works.
Message Edited by SarahB on 05-17-2007 09:55 AM
Sarah
Applications Engineer | National Instruments | UK & Ireland
Attachments:
Counters.jpg ‏21 KB

Hi total noob here, any good tutorials on how to use garage band?

Any one know of any good tutorials on the general use of garage band '11 for a complete beginner? I am just getting started and would like a decent walk through. Any suggestions?

daveridesbikes wrote:
Thank you that is exactly what I am looking for, ...
You're Welcome...
daveridesbikes wrote:
... But who hasnt wanted to be a rock star at some point?
No kidding...
Enjoy your voyage of discovery...

Needs help.....Please about using different classes

I don't know how to use differenet classes.
Please tell me how to write class to suit Start. This stuff me up. Please .... help me
<<My program>>
//Start
public class Start
{ private Artist[] Artists;
private Record[] records;
private Person[] Manager;
private TextMenu makeMenu = new TextMenu();
public static void main(String[] args)
     Start studio = new Start();
studio.menu();
public Start()
{ //Person.Manager(ManagerName,HouseNumber,StreetNumber,PhoneNumber)
     Manager = new Person[1];
     Manager[0] = new Person("Yangfan",88,"Young ST",11118888);
     //Artist(GroupID,ArtistName,HouseNumber,StreetNumber,PhoneNumber)
     Artists = new Artist[5];
Artists[0] = new Artist(1,"Backstreet Boys",58,"Music ST",99998888);
Artists[1] = new Artist(2,"Santana",68,"Music ST",99998899);
Artists[2] = new Artist(3,"Macy Gray",78,"Music ST",55558888);
Artists[3] = new Artist(4,"Ricky Martin",88,"Music AVE",77778888);
Artists[4] = new Artist(5,"Did Rock",55,"Music Road",66667777);
//Record(RecordingID,RecordName,Artist,StartTime,FinishTime,RecordingDate,GuestArtist1,GuestArtist2)
records = new Record[6];
records[0] = new Record(1,"I want it that way",Artists[0],11,12,"05/08/2001",Artists[1],Artists[3]);
records[1] = new Record(2,"Smooth",Artists[1],11,12,"05/08/2001",Artists[1],"");
records[2] = new Record(3,"Do something",Artists[2],11,"05/08/2001",Artists[3],"");
records[3] = new Record(4,"Livin La Vida Loca",Artists[3],11,12,"05/08/2001",Artists[1],Artists[3]);
records[4] = new Record(5,"Bawitdaba",Artists[4],11,13,"05/08/2001",Artists[1],"");
records[5] = new Record(6,"The one",Artists[0],11,14,"05/08/2001",Artists[1],"");
public void menu()
{ String[] choices = {">>>List Manager Details",">>>List All Artist Names",">>>List An Artist Telephone-Number",">>>Show Details For One Recording",">>>Add A New Recording",">>>List The Recording Costs For All Artists",">>>List Artist's Reocording",">>>Exit Program"};
while (true)
{ switch (makeMenu.getChoice(choices))
{ case 1: showAllArtists();
break;
case 2: showAllRecords();
break;
case 3: System.exit(0);
break;
case 4: System.exit(0);
break;
case 5: System.exit(0);
break;
case 6: System.exit(0);
break;
case 7: System.exit(0);
break;
case 8: System.exit(0);
break;
default:
public void showAllArtists()
{ int numArtists = Artists.length;
for(int i = 0; i < numArtists; i++)
{ Artists[i].displayArtistDetails();
public void showAllRecords()
{ for (int i = 0; i < records.length; i++)
{ System.out.println();
records.printRecordDetails();
<<Assignment>>
Due - midnight, Wednesday August 22nd
This assignment will test your knowledge of Java programming using classes, encapsulation and javadoc.
The base requirements
Write a complete Java class to manage a Digital Recording Studio. The studio wants to keep a list of all Artists that use the studio and also wishes to keep track of all Recordings that have been made. An important function of the program is to calculate the time spent making a recording and charge the Artist for the time used.
You must create at least the following classes, Start, Studio, Person, Artist, Recording, Address. You may create other classes if needed as well
Start will contain main(), create one instance of a Studio and execute a Menu of commands to test your code. Studio should contain a studio name, an array of Artist and an array of Recording plus the studio manager (a Person). Each Artist should contain the name of the group and an Address. Each Person will have a name and a home address. Each recording will have a Title (usually song title), an Artist (only one), and a list of guestArtist (they are Artist�s but will not receive royalties) the number of the CD the recording is stored on (numbers are numerical and recordings are saved on CD-R), plus the recording start and finish times for the recording session (suggest you use Java Date class � refer to the API). An Address will contain, house number (integers only), a street name and a telephone number. There is no need to store city and country.
To enter a set of data for testing your program � main() should call a method in the Start class that will fill in a set of values by creating objects and filling in values by calling methods in each class. This is the ONLY method allowed to be longer than 1 page long � normally we would read the data from a file but there are no O-O principles that can be learnt with simply filling in data values. It is suggested to create say at least 4 Artist�s and 6 Recordings (at least one with 1 guest Artist and one with 2 guestArtist�s)
A menu for testing your program should be provided (it is suggested to put the Menu into a separate class as you need at least 3 menus). While other commands are possible, only the following ones will receive marks.
Menu commands needed are
List the Managers name, address and telephone number
List all Artist Names
List an Artist telephone number (a sub menu showing valid Artist�s is required)
Show all details for one Recording ( sub menu of valid Recordings will be needed and remember there can be more than one guestArtist)
Add a new Recording, user will need to be prompted for all details.
List the recording costs for all Artists � show each Artist on a separate line with their name and total amount, charge for using the studio is $1000 per hour or part thereof, example for a 1 hour and 10 minute recording the Artist will be billed for 2 hours.
List all the Recording�s one Artist has worked on (sub menu of Artists needed), the list should show whether they were the Artist or a guestArtist
Exit program
Use fixed sizes for arrays, suggest 20 is suitable for all arrays. Java can handle dynamic data structures (where the number of elements can grow or shrink), but that is beyond a first assignment.
Do NOT make ANY methods static - this defeats the Object Oriented approach and will result in ZERO marks for the entire assignment.
Data MUST be encapsulated, this means that all the data relating to an object are to be stored INSIDE an object. None of the data detail is to be globally available within your program - hence do not store Artist names in either Studio or Recordings � just store a reference instead. Do NOT create ID numbers for Artists, you should use References instead � for many students this will be the hardest part as you have to use Objects, not program in a C style to solve the problem. Note that if there are any non-private data in classes then zero will given for marks for encapsulation.
Good programming style is expected (see web page or lecture notes). In particular, you must use javadoc to generate a set of html pages for your classes. Make sure you use the special javadoc style comments in your source code. Marks will be granted for both using javadoc and also for including sensible javadoc comments on each class and each public method.
What to Hand In
Read the turnin page, basically the .java files, a readme.txt to tell the marker which file the program starts from plus the javadoc (html) files. Do NOT send .class files (if you do send these we will delete them and recompile your program), do NOT compress with gtar, tar, zip or use any other tool on your files. Turnin automatically compresses all your files into a single archive for us to mark.
The simplest way to turnin all your files is to place all files in one directory then just use the *.* wildcard to turn in all files within that one directory.
You must turnin all files that are not part of Java 1.3. In particular, you are allowed (actually encouraged) to use EasyIn or SavitchIn but should include the one you use in the files you submit. It is STRONGLY suggested that you copy all the files into another directory, test it works there by compiling and executing then turnin files from that directory. A common problem is students adding comments at the last minute then not testing if it still compiles. The assignment will be marked as submitted � no asking later for leniency because you added comments at the last minute and failed to check if it still worked.
If the tutors are unable to compile your submission, they will mark the source code but you will lose all the execution marks. Sorry, but it is your responsibility to test then hand in all files.
Comments
For CS807 students, this program should be fairly easy if it was to be programmed in C (you would use several struct). The real art here is to change over to programming objects. Data is contained in an object and is not global. This idea is essential to using Java effectively and is termed encapsulation. Instead of using function(data), you use objectName.method( ). Effectively you switch the data and functions around, the data has a method (function) attached to it, not the other way around as in C (where you have a function and send data to it).
While there will be some marks for execution, the majority of the marks will be given for how well you write your code (including comments and documentation) and for how well you used O-O principles. Programs written in a C style with most of the code in one class or using static will receive ZERO marks regardless of how well they work.
You are responsible for checking your turnin by reading the messages turnin responds with. Failure to read these messages will not be an acceptable excuse for submitting an incorrect assignment. About 2% of assignments sent to turnin are unreadable (usually empty) and obtain 0.
Late submissions
Late submissions will only be accepted with valid reasons for being late. All requests for assignment extensions must be made via email to the lecturer. Replies for acceptance or refusal will made by email. Instant replies are unrealistic (there is usually a flood of queries into my mail box around assignment due dates) and the best advice is to ask at least 4 days in advance so that you will have a reasonable chance of getting a timely reply and allow yourself enough time to submit something on time if the extension is not granted.
ALL late submissions will be marked LAST and will NOT be sent to tutors for marking until all other assignments have been marked. As an example, if you submit late and your assignment is not yet marked by the time assignment 2 is due then it will be pushed to the end of the marking pile as the assignments that were submitted on time for assignment 2 will take priority.
If you make a second submission after the submission date, only the first submission will be marked. We will not mark assignments twice! You can update your submission BEFORE the submission date if you need to - this will just overwrite the first submission. The latest time for a late submission is 5pm on the Wednesday after the due date. This is because, either a solution will be handed out at that lecture or details of the assignment will be discussed at the lecture. I cannot accept any assignment submissions after that time for any reason at all including medical or other valid reasons. For those who are given permission to be later than the maximum submission time � a different assignment will be handed out. Remember, if you decide to submit late you are VERY UNLIKELY to receive feedback on your assignments during semester.
Assignments will be removed from turnin and archived elsewhere then forwarded to tutors for marking on the morning after the assignment is due. A different tutor will mark each of your assignments � do not expect the tutor you see at the tutorials to be your marker.
Marks will be returned via email to your computer science yallara account � ideally within 2 weeks. I will send marks out when I receive them so do not send email asking where your marks are just because a friend has theirs. If you want your email forwarded to an external account, then place a valid .forward file into your yallara account. The Help Desk on level 10 can assist you in setting this up if you do not know how to do it.

I have seen other people who have blatantly asked for
other people to do their homework for them, but you
are the first person I've seen to actually cut and
paste the entire assignment as it was handed to you.
Amazing.
Well, unlike some of the people you're talking about, it seems like zyangfan did at least take a stab at it himself, and does have a question that is somewhat more sepcific that "please do this homework for me."
Zyangfan,
marendoj is right, though. Posting the entire assignment is kind of tacky. If you want to post some of it to show us what you're trying to do, please trim it down to the essential points. We don't need to see all the instructor's policies and such.
Anyway, let me see if I understand what you're asking. You said that you know how to write the code, but only by putting it all in one class, is that right? What part about using separate classes do you not understand? Do you not know how to make code in one class aware that the other class exists? Do you not know how code in class A can call a method in class B?
Please be a bit more specifice about what you don't understand. And at least try using multiple classes, then when you can't figure out why something doesn't work, explain what you did, and what you think should have happened, and what did happen instead.
To get you started on the basics (and this should have been covered in your course), you write the code for two classes just like for one class. That is, for class A, you create a file A.java and compile it to A.class. For class B, you create a file B.java and compile it to B.class. Given how rudimentary you question is, we'll skip packages for now. Just put all your class files in the same directory, and don't declare packages in the .java files.
To call a method in class B from code that's in class A, you'll need an object of class B. You instantiate a B, and then call its methods.
public class B {
int count;
public B() { // constructor
public void increment() {
    count++;
public class A {
public static void main(String args[]) {
    B b = new B();
    b.increment();
}Is this what you were asking?

How to use TableSorter class with DefaultTableModel

Hi Friends
Please tell me how to use TableSorter Class which is in the Java. Tutorials with DefaultTableModel.
i saw in a thread there it was given that we have to pass the DefaultTableModel to the TableSorter Class.
I tried to use like that. But i am getting Error Like Exception occurred during event dispatching:
I am posting the part of Code where i use the DefaultTableModel
     private void displayavailablity(String selectedAuthor)
               try
                    Vector columnNames = new Vector();
                    Vector data1 = new Vector();
                    String bname,bauthor,bcategory,bref1,bavail,bid;
                    int bref,mid,num;
                    rs = st.executeQuery("SELECT BId,BName,BAuthorName,BAuthorandPublisher,BCat FROM Books where BAuthorandPublisher='" +selectedAuthor+"'");
                    ResultSetMetaData md= rs.getMetaData();
                    int columns =md.getColumnCount();
                    String booktblheading[]={"NUMBER","BOOK NAME","AUTHOR","CODE","CATEGORY"};
                    for(int i=1; i<= booktblheading.length;i++)
                         columnNames.addElement(booktblheading[i-1]);
                    while(rs.next())
                         Vector row = new Vector(columns);
                         for(int i=1;i<=columns;i++)
                              row.addElement(rs.getObject(i));
                         data1.addElement(row);
                         //System.out.println("data is:"+data);
                    ((DefaultTableModel)table.getModel()).setDataVector(data1,columnNames);
                    TableSorter sorter = new TableSorter((DefaultTableModel)table.getModel());
                    rs.close();
               catch(SQLException ex)
                    System.out.println("ERROR IS HERE");
                    ex.printStackTrace();
     }Please help me on this issue Otherwise Please give me some Sample coding to implement this sorting. with DefaultTableModel
Thank you for your service
Cheers
Jofin

I don't know about any TableSorter class, but I suppose you mean javax.swing.table.TableRowSorter.
The TableRowSorter is to be attached to the JTable, not to the data model. Here's a cut'n'paste from the last time I used it:
RowSorter<TableModel> sorter = new TableRowSorter<TableModel>(tableModel);
myTable.setRowSorter(sorter);
And heres from the JDK1.6 documentation:
TableModel myModel = createMyTableModel();
JTable table = new JTable(myModel);
table.setRowSorter(new TableRowSorter(myModel));
Check out http://java.sun.com/javase/6/docs/api/javax/swing/table/TableRowSorter.html. I find it to be good documentation.

Why Use Nested Classes

Hi All,
Why do we use Nested Classes ? Explain it with example ....
If we say - It is a way of logically grouping classes that are only used in one place. Then we can say we use it through "Package" so why inner class ??
Thanks in advance ....

A real life example to jschell's explaination may be this.
The pistons in your automobile engine are encapsulated by the engine block -- or the engine block encapsulates the pistons inside. This is the desired effect because as soon as we take the pistons out of the engine block, and put them say, in the backseat of the car instead, they no longer perform the function they were intended. There is another side effect to this analogy. When the pistons are properly installed in the engine block, there is only one movement the pistons can move -- up and down movement, that's it... they cannot rotate, spin, twist around or anything inside the engin block. Furthermore, the up and down movement is the only useful thing a piston can do. As soon as we throw the pistons in the backseat of the car, they can roll around, spin, and generally rotate to any configuration or orientation -- which does not produce any useful power.
Inner classes are generally the same way. So we can see this example with a little code -- which we like.
public class Engine
Piston[] pistons = new Piston[8];
class Piston
// the usual methods here..
}Of course, if your program is extremely sohisticated, this may not be a good solution -- for example, if you are making a catalog of automotive parts, then you would probably want your <tt>Piston</tt> class to be stand-alone.
Edited by: pierrot_2. Also notice that the class <tt>Piston</tt> is not an INNER class of Backseat!

Good tutorial for using E63 and how to add extras ...

I got this phone a week ago and still learning. I did not find the user manual very helpful. Any good tutorials that anyone can recommend?
Secondly, I want to add the calculator, alarm clock etc to the home screen. Is it possible to do?
Then I need advice on Ovi, never worked on it.
Any links would be appreciated

Thanks but I want to try to use the orielly servlet class I need some practice using servlets as I am relying on jsp's too much.
Anybody have any pointers on the orielly upload servlet and how to use it.

Encryption? Anyone good at explaining how it is done?

Hi!
Didn't really know where to put this, so move it if this is the wrong part of the forum...
Well, my question to everyone is, how many of you use cryptation on your partitions? and if so, can someone write a tutorial in the wiki on how to do it?
I've been looking for good tutorials, and I can't seem to find any that are good...I would really like to start cryptateing my partitions, I know that it often aint that hard to break for a fbi-guy, but it might make it harder for people that aint suppose to have my data ...
The problem is that I don't feel confident how it works...so if anyone wanna explain and maybe put something up in the wiki that would be great !!
/CyberTron

A terse example of creating an encrypted filesystem image. You can do it with real block devices (/dev/hda1) too.
# dd if=/dev/zero of=fs.img bs=1024 count=1048576
# losetup /dev/loop/0 fs.img
# cryptsetup create myfs /dev/loop/0
# mke2fs /dev/mapper/myfs
# mount /dev/mapper/myfs /mnt
< read/write/copy >
# umount /mnt
# cryptsetup remove myfs
# losetup -d /dev/loop/0
The losetup stuff is only required since I'm using a file to store my filesystem. If you use a real block device, you don't need any loop devices.

Design question about when to use inner classes for models

This is a general design question about when to use inner classes or separate classes when dealing with table models and such. Typically I'd want to have everything related to a table within one classes, but looking at some tutorials that teach how to add a button to a table I'm finding that you have to implement quite a sophisticated tablemodel which, if nothing else, is somewhat unweildy to put as an inner class.
The tutorial I'm following in particular is this one:
http://www.devx.com/getHelpOn/10MinuteSolution/20425
I was just wondering if somebody can give me their personal opinion as to when they would place that abstracttablemodel into a separate class and when they would just have it as an inner class. I guess re-usability is one consideration, but just wanted to get some good design suggestions.

It's funny that you mention that because I was comparing how the example I linked to above creates a usable button in the table and how you implemented it in another thread where you used a ButtonColumn object. I was trying to compare both implementations, but being a newbie at this, they seemed entirely different from each other. The way I understand it with the example above is that it creates a TableRenderer which should be able to render any component object, then it sets the defaultRenderer to the default and JButton.Class' renderer to that custom renderer. I don't totally understand your design in the thread
http://forum.java.sun.com/thread.jspa?forumID=57&threadID=680674
quite yet, but it's implemented in quite a bit different way. Like I was saying the buttonClass that you created seem to be creating an object of which function I don't quite see. It looks more like a method, but I'm still trying to see how you did it, since it obviously worked.
Man adding a button to a table is much more difficult than I imagined.
Message was edited by:
deadseasquirrels

Why to use wrapper class?

hello,
can anybody please tell me why wrapper class are used in JAVA and what are exactly wrapper class?
reply me soon....

I want to give an example and then explain why it is for. Primitives will be good example for this situation.
Example:
Below are the primitive types and their wrapper classes...
Primitive to Wrapper Class
byte - Byte
short - Short
int - Integer
long - Long
char - Character
float - Float
double - Double
boolean - Boolean
USING OBJECT CREATION
Think a situation when you create an integer object using this code:
---> Integer intVar = new Integer();
you have the methods and constants:
1 MAX_VALUE ,
2 MIN_VALUE ,
3 byteValue() ,
4 compareTo(Integer anotherInteger) ,
5 compareTo(Object o) ,
6 decode(String nm) ,
7 doubleValue() ,
8 equals(Object obj) ,
9 floatValue() ,
10 getInteger(String nm) ,
11 getInteger(String nm, int val) ,
12 getInteger(String nm, Integer val) ,
13 hashCode() ,
14 intValue() ,
15 longValue() ,
16 parseInt(String s) ,
17 parseInt(String s, int radix) ,
18 shortValue() ,
19 toBinaryString(int i) ,
20 toHexString(int i) ,
21 toOctalString(int i) ,
22 toString(),
23 toString(int i) ,
24 toString(int i, int radix) ,
25 valueOf(String s) ,
26 valueOf(String s, int radix)
now you have an object with 2 constants and 24 methods.
USING WRAPPER CLASS
and think using wrapper class of Integer..
CODE ---> int intVar = Integer.parseInt((String)someStringData);
In this case your Integer object have the methods and constants
1 MAX_VALUE ,
2 MIN_VALUE ,
3 parseInt(String s) ,
4 parseInt(String s, int radix) ,
5 toBinaryString(int i) ,
6 toHexString(int i) ,
7 toOctalString(int i) ,
8 toString(int i) ,
9 toString(int i, int radix) ,
10 valueOf(String s) ,
11 valueOf(String s, int radix)
as you in this situation you have 2 constants and 9 methods.
AS YOU SEE THERE ARE 15 METHODS DIFFERENCE FROM THE OBJECT AND THE WRAPPER CLASS OF INTEGER OBJECT.
NOW TALKING ABOUT PRIMITIVE TYPES ALL PROGRAMMERS USED THIS TYPES FOR THEIR CODES AND THEY ALWAYS NEED SOME THIS KIND OF CASTING. IN MY EXAMPLE I TAKE THE VALUE OF AN STRING VARIABLE. AND THERE ARE LOTS OF THINGS SIMILIAR TO THIS EXAMPLE.
IDEA OF THIS WRAPPER CLASSES IS THAT USE AS YOU NEED NOTHING MORE. IN THE WRAPPER CLASS YOU DONT HAVE INTEGER OBJECT. YOU ONLY NEED THE PARSEINT METHOD OF INTEGER OBJECT INSTEAD OF CREATING THE INTEGER OBJECT YOU USE THE WRAPPER CLASS OF THIS TYPE...
OBJECTS ARE STORED IN A MEMORY PLACE CALLED HEAP WHICH IS PLACED ON RAM AND GARBAGING OF THIS OBJECTS TAKES MORE TIME TO ALLOCATE FROM HEAP STORAGE.
AND ANOTHER NOTE FOR THIS WRAPPER CLASSES if you want to store an int inside a container such as an ArrayList (which takes only Object references), you can wrap your int inside the standard library Integer class
EX:
import java.util.*;
public class ImmutableInteger {
public static void main(String[] args) {
List v = new ArrayList();
for(int i = 0; i < 10; i++)
v.add(new Integer(i));
// But how do you change the int inside the Integer?
} ///:~
GOOD LUCK...
REALKINGTA....

Creating a triangle using polygon class problem, URGENT??

Hi i am creating a triangle using polygon class which will eventually be used in a game where by a user clicks on the screen and triangles appear.
class MainWindow extends Frame
     private Polygon[] m_polyTriangleArr;
                   MainWindow()
                          m_nTrianglesToDraw = 0;
         m_nTrianglesDrawn = 0;
                         m_polyTriangleArr = new Polygon[15];
                         addMouseListener(new MouseCatcher() );
        setVisible(true);
                     class MouseCatcher extends MouseAdapter
                         public void mousePressed(MouseEvent evt)
              Point ptMouse = new Point();
              ptMouse = evt.getPoint();
            if(m_nTrianglesDrawn < m_nTrianglesToDraw)
                            int npoints = 3;
                    m_polyTriangleArr[m_nTrianglesDrawn]
                  = new Polygon( ptMouse[].x, ptMouse[].y, npoints);
}When i compile my code i get the following error message:
Class Expected
')' expectedThe two error messages are refering to the section new Polygon(....)
line. Please help

Cannot find symbol constructor Polygon(int, int, int)
Can some one tell me where this needs to go and what i should generally
look like pleaseI don't think it is a good idea to try and add the constructor that the compiler
can't find. Instead you should use the constructor that already exists
in the Polygon class: ie the one that looks like Polygon(int[], int[], int).
But this requires you to pass two int arrays and not two ints as you
are doing at the moment. As you have seen, evt.getPoint() only supplies
you with a single pair of ints: the x- and y-coordinates of where the mouse
button was pressed.
And this is the root of the problem. To draw a triangle you need three
points. From these three points you can build up two arrays: one containing
the x-coordinates and one containing the y-coordinates. It is these two
arrays that will be used as the first two arguments to the Polygon constructor.
So your task is to figure out how you can respond to mouse presses
correctly, and only try and add a new triangle when you have all three of its
vertices.
[Edit] This assumes that you expect the user to specify all three vertices of the
triangle. If this isn't the case, say what you do expect.

Uploading bitmapData using FileReference class ?

Hi gurus ;)
Question nr 1.
Is it possibly to upload bitmapData to server using
FileReference class ? How should i approach this issue, is there
any ready classes available for this purpose. I'm generating
bitmaps inside my Flash/Flex App and need to store them under users
profile in server.
Question nr 2.
Can i upload files from remote server to another using
FileReference class
e.g Somehow like :
uploadURL = new URLRequest();
uploadURL.url = "
http://www.[yourDomain
fileURL.url = "
http://www.myLocation.com/myfile.JPG";
file = new FileReference(fileURL.url);
file.upload(uploadURL);
This is just an idea, sure not working ;)
Any ideas are helpful
Thx
iquaaani

I did a small application that uploads a file to the server
every hour. If the server response that a login is required to
upload the file, it goes to a login page to do the login and
retried to upload the file.
I got the server response in order to know if the file did
upload correctly or not (I have to send more form data than just
the file). I didn't try the mime type since it's not relevant for
my application and usualy this information is not very trust worthy
anyways.
I'm not sure what you mean with exceptions, if you are
referring to HTTP errors, I think there is an event for that, but I
used the IOError event for this, and it seems to work good
also.

Add jar files and use those classes at the runtime

Hi All,
I need to add some jar files at the runtime depends on which the user selects where the jar file is located and i need to import those classes in other class for some functionalities . I could add jar files by using the URLClassLoader and Class.forName("myjar.myclassname") is also succeeded and i have no clue how to use those classes with in the jar file as i couldn't import those classes also in the source because the jar files are being added at the runtime(This leads to class not found exception at the compile time).
I had found a complicated way of using those classes after being added at the run time as below.
   Class clazz = Class.forName(myClass);
            final Method method = clazz.getDeclaredMethod(requiredMethod, new Class[]{URL.class});
            final Object returned = method.invoke(clazz.newInstance(), new Object[]{request}); but, its really pain to use in this way in all the places.
Does any of you have simpler suggestions on how to achieve this?
Thanks,
Venky.

Thanks jschell. Yes, you are right. I had found that using reflection API is the only way to load classes at the run time. But according to our application using reflection makes the application little complex, so while start of the application or during other modifications, i am overwriting my jar file to the latest one using FileChannel class as below
      FileChannel ic = new FileInputStream("new.jar").getChannel();
      FileChannel oc = new FileOutputStream("old.jar").getChannel();
      ic.transferTo(0, ic.size(), oc);
      ic.close();
      oc.close();After this code is executed, our application totally uses the new jar file.It is little fast than using reflection. Is this a good idea?

Good tutorials explain use of classes

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