Beginner Java questions

Hello:
I'm looking for some guidance on a few things I am confused on. Can somebody tell me or point me in the right direction on how you would write and equivalent compound statement for
x = 2 * x;
sum = sum + num;
y = y / (x +5);
lastly
What type of input would I use for :
import java.util.*;
public class Strange
static Scanner console = new Scanner (System.in);
public static void main (String[ ] arg)
int x;
int y;
String name:
x = console.nextInt ();
name = console.nextLine ();
y = console.nextInt ();
I appreciate any guidance and help provided on this. I'm struggling to wrap my head around some of these things.

eaolson wrote:
BigDaddyLoveHandles wrote:
This is obviously a homework question. Please don't expect anyone here to do your homework for you.Well, if you notice, he's asking for "guidance" and for people to "point him in the right direction". He's not stating a problem and demanding a solution like so many others. If you ask me, he's asking for help with homework in exactly the right way.
For the first question, I would suggest reviewing this section and the following ones of the Java Tutorials:
http://java.sun.com/docs/books/tutorial/java/nutsandbolts/operators.html
http://java.sun.com/docs/books/tutorial/java/nutsandbolts/op1.html
I don't understand what the second question is asking for.In reply #2 the OP tried to clarify the second question:
Well, I'm tasked wtith stating "what type of input the progragms requires and in what order the input must be provided" for the program I stated. >Beyond that, I'm not sure either and that's why I'm looking for help. "Looking for help", eh?

Similar Messages

Very Beginner Java Question

Using Java, what kind of loop, test, and code would you use to create a simple 3 pixel thick black border on the inside of an image?

In pseudocode drawing the top and bottom lines might look like:
FOR i FROM 0 TO width-1
    setToBlack (i,0)
    setToBlack(i,height-1)
    setToBlack(i,1)
    setToBlack(i,height-2)
    setToBlack(i,2)
    setToBlack(i,height-3)I'm assuming width and height are variables that you would figure out from the image. The image runs from the pixel I'm calling (0,0) to (width-1,height-1).
Exactly how you would set a pixel to black depends on what sort of image it is. The BufferedImage class has a method to do this.
The vertical borders use a similar loop.
Notice I haven't used a nested for loop. You might change it to use a nested for loop if you wanted to deal with borders of different thicknesses. Something along the lines of
FOR x FORM 0 TO width-1
    FOR t FROM 0 TO thickness-1
        setToBlack(i,t)
        setToBlack(i,height-t-1)A small complication arises in that for very narrow or short images the pixels you are trying to change might not be "legal".
FOR x FROM 0 TO width-1
    FOR t FROM 0 TO thickness-1
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Beginner font questions

These are some beginner font questions if someone has the time/patience.
I've never paid much attention to fonts over the years, never installed
any other than those that might have come with applications. Early on,
15 years ago or so, I settled on Palatino and I've stayed with it for
most docs (Word 5.1a and now Word vX) and often for other apps (Safari,
Now).
I just upgraded to Tiger (10.4.4) and I use Word vX.
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Tiger that OS X is getting it from my OS 9 System folder for Classic.
It does not look like Palatino is in any other locations including MS
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3. If I decide to stop using Classic, and I'm close to that time, can I
transfer those fonts to OS X? If so, to which location is best.
4. And are the same fonts used for printing and screen? In other words
back in pre OS X days I thought some fonts came in screen versions and
print versions but my memory is hazy on that. Not only that.
Thank you for any education or links for info.
Powerbook G4 Ti Mac OS X (10.4.4)

1. I gather from looking at Font Book that when I'm
using Palatino in
Tiger that OS X is getting it from my OS 9 System
folder for Classic.
It does not look like Palatino is in any other
locations including MS
Office vX. Does that make sense?
That's correct.
2. I always thought that Palatino was a very basic,
always available
font. Not so?
It seems to be out of favor.
3. If I decide to stop using Classic, and I'm close
to that time, can I
transfer those fonts to OS X? If so, to which
location is best.
Yes, you can just put it in Users/username/Library/Fonts (or Library/Fonts for all users).

Java Question... please help

I am running Snow Leopard (mac os x version 10.6.8)
For the past couple of years I've played gin in yahoo games.
Yesterday when I entered the gin lobby ...the font was so tiny
I wasn't able to read it.   I checked Java on my computer and
it is enabled, however I just realized when I go into the gin
lobby... there is no java icon on the dock.   Since the font size
is fine in all other applications, I am presuming this is a Java
issue.
Help if you are able.. please and thanks

Huh? Is this a Java question? Where's the Java? I just see a little JavaScript. Do you know how to use servlets and JSPs?
Jesper

What kind of Java questions can I ask?

Here's a change:
I want to interview some good java people. I have lots of Java questions in mind which I could ask them, however fellow JavaGuru's
I would like some potential questions from you which I could ask someone who claims he/she is a good java programmer??
I am asking because I want to be as fair as possible to the applicant and not ask them questions which I think are tough etc...

Touchy subject.
The language is not as important, as understanding programming concepts.
So fine, when the programmer's horizont involves some abstraction levels.
If a programmer can write an UML class diagram for a linked list.
If a programmer knows a design pattern Singleton.
If a programmer can write his/her own single linked list class with sorted insertion.
Language concepts:
- Why:
import java.util.*;
Map map = new HashMap();
- Answer:
Hiding the choice of implementation (HashMap) by using the more general
interface Map.
Don't expect much on an interview though. The situation might not be
adequate to distinghuish between the good and the bad apples.
Talking code is a good starting point, code of your making unfortunately.
A good programmer will hesitate to show really useful code.
A bad programmer might have stolen his/her code.
The problem you might have, that you are in search of an expert, not
having the expertise in-house. In that case you might get a better
picture, talking about which IDE would be opportune, whether he/she
has experience with the source version system CVS, what would his/her
ideas be about coming projects.
That would establish a common line of communication.

Interesting Java Questions. Need answers Pls

Hi All,
I have come accross few java question, could any one please provide best answers please?
1. Why the wait() method is there in the Object class? Not in the Threads?
2. Why JDBC has all interfaces & not classes?
3. Which type of collection do u prefer to make the incoming objects in sort order?
4. Why the hasCode() method should be implemented if we are overiding the equals(0 method?
Please provide me best answers ASAP.
Girish.K

do u prefer tohttp://www.catb.org/~esr/faqs/smart-questions.html#writewell
How To Ask Questions The Smart Way
Eric Steven Raymond
Rick Moen
Write in clear, grammatical, correctly-spelled language
We've found by experience that people who are careless and sloppy writers are usually also careless and sloppy at thinking and coding (often enough to bet on, anyway). Answering questions for careless and sloppy thinkers is not rewarding; we'd rather spend our time elsewhere.
So expressing your question clearly and well is important. If you can't be bothered to do that, we can't be bothered to pay attention. Spend the extra effort to polish your language. It doesn't have to be stiff or formal - in fact, hacker culture values informal, slangy and humorous language used with precision. But it has to be precise; there has to be some indication that you're thinking and paying attention.
Spell, punctuate, and capitalize correctly. Don't confuse "its" with "it's", "loose" with "lose", or "discrete" with "discreet". Don't TYPE IN ALL CAPS; this is read as shouting and considered rude. (All-smalls is only slightly less annoying, as it's difficult to read. Alan Cox can get away with it, but you can't.)
More generally, if you write like a semi-literate b o o b you will very likely be ignored. So don't use instant-messaging shortcuts. Spelling "you" as "u" makes you look like a semi-literate b o o b to save two entire keystrokes.

Beginner XCode/Java Question - printf problem

Hello,
I have just started playing around with XCode and Java. I entered the statement:
System.out.printf("%s\n%s\n", "Welcome to", "Java Programming!");
into the default working java project (File -> New Project -> Java Tool) and Im getting the error "cannot find symbol" after I compiled it. I do not believe this is a syntax error since it was copied straight from a textbook. So, my questions are:
1. What "symbol" is Xcode refering to?
2. Does Xcode coem with the latest version of Java?
3. How can I check the Java version?
4. Is there a library that needs to be imported to get it working?
Thanks in advance!

Hi Arcus
I think you might have to change some of the Xcode settings to force it to use Java 1.5. Try this:
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Best wishes
Bob

Beginner's Question on simulation of java card application

Hi,
I am trying to run a basic Java card application.
To simulate the java card application, I created jcwde.app and tried C:\>jcwde -p 9025 jcwde.app
I got and exception like:
Exception in thread "main" java.lang.UnsatisfiedLinkError: markHeap
at com.sun.javacard.impl.NativeMethods.markHeap(Native Method)
at javacard.framework.Dispatcher.cardInit(Dispatcher.java:188)
at javacard.framework.Dispatcher.main(Dispatcher.java:63)
at javacard.framework.JCWDEDispatcher.main(JCWDEDispatcher.java:28)
at com.sun.javacard.jcwde.Main.run(Main.java:85)
at com.sun.javacard.jcwde.Main.main(Main.java:148)
Can anyone help me to find out the reason for this exception?
The content of jcwde.app is
// applet AID
com.sun.javacard.installer.InstallerApplet 0xa0:0x0:0x0:0x0:0x62:0x3:0x1:0x8:0x1
wallet.Wallet
Thanx in advance.
anju

I see terms like ...
Core Java: The main libraries.
JDK: (J)ava (D)evelopement (K)it) - AKA: (S)oftware (D)evelopement (K)it although the terms are not exactly synonomous
J2EE:(J)ava 2 (E)nterprise (E)dition (builds on the J2SE with additional librarities for true business application building)
J2SE: (J)ava 2 (S)tandard (E)dition (The core libraries for general Java program developement, w/o the extra stuff that is in the J2EE
Go to java.sun.com and check out the tutorials, the readme files that come with the downloads, the release notes, etc ... HTH

JAVA questions coming from a windows world..

Hello.. I consider myself a beginner in JAVA programming.
I have some windows questions related to SUN Java.
1. How do I connect to the windows registry (local/remote) using JAVA?
2. How do I call/get/set Windows WMI on windows system from JAVA?
3. How to I run system specific commands (ex. dir c:) and use the output in JAVA?
4. Is there a way to edit INI files, including listing/editing parameters, adding values etc?
5. Can I call windows components (ActiveX Library) or DLL from java?
6. What are the advantages og using JAVA compared to .NET
7. How good are JAVA IDEs (Netbean, IntelliJ, SunOne, Eclipse etc) compared to VS .NET?
8. What�s the difference between J2ME, J2SE and J2EE?
9. What�s the difference between Servlet and JSP?
I would appreciate serious answers related to any of the above.
/W.

1. How do I connect to the windows registry (local/remote) using JAVA?
jst.jar
2. How do I call/get/set Windows WMI on windows system from JAVA?
whats WMI ?
3. How to I run system specific commands (ex. dir c:) and use the output in JAVA?
Runtime.execCommand(), although i am kinda curious why you need the dir c: executed
4. Is there a way to edit INI files, including listing/editing parameters, adding values etc?
Offcourse, Java come with a very complete IO package and even more IO has been added in java 1.4
5. Can I call windows components (ActiveX Library) or DLL from java?
Yes
6. What are the advantages og using JAVA compared to .NET
Java is alot broader then .NET
7. How good are JAVA IDEs (Netbean, IntelliJ, SunOne, Eclipse etc) compared to VS .NET?
No idea, but Intellij really is very good.
8. What�s the difference between J2ME, J2SE and J2EE?
see http://java.sun.com/
9. What�s the difference between Servlet and JSP?
One is a class , the other gets translaed into a class

Beginner: some questions

Hello all,
I am just a beginner for EJB, and writing a simple example of EJB. Some questions confuse me.
1.     about server
I just use JDK1.3.1 and JSDKEE1.3, is it all right? Do I need another things, for instance, weblogic ( what is this?)?
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I wrote some code( CMP) include: home interface, remote interface, implement class, and primary key. Now , deploy it? Use ��C:\j2sdkee1.3\bin\deploytool�� command, is it?
I thought every EJB need a XML deployment descriptor, my question is: I write this by myself or use deploytool?
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I notice some example use Cloudscape, is this database? Whether can I use another database, for instance, MS Access? If I can, how to access it in CMP, and what is the ��Database JNDI Name��( if I use MS Access) when I deploy using deploytool?
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if I finish coding, then compile, and deploy, now, is it OK? I mean, I should move some file to special direction? (I remember the .class file is placed in special direction when I use servlets. )(suppose: I work in C:\mybean. Every file in it)
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1. No you do not need anything other than J2SE 1.3.1 and J2EE SDK 1.3 J2EE SDK 1.3 includes a reference implementation that you can use to do pretty much everything that is J2EE platform standard.
Products such as WebLogic, WebSphere are comercial implementations of J2EE platform specifications. And you would use them for commercial/production quality applications.
See http://java.sun.com/j2ee/faq.html Especially the questions about using reference implementation.
2. You as a developer write the deployment descriptor and the deployment engineer customizes it if required at deployment time.
3. You can use JDBC-ODB driver to work with Microsoft Access databse.
See http://java.sun.com/j2se/1.3/docs/guide/jdbc/getstart/bridge.doc.html#996747
4. No. The files go to the right place at deploy time.
5. No. If you have J2SE 1.3.1 and J2EE SDK 1.3, you arealready on your way to achieving EJBs.

Simple basic java question

public static void main(String[] args)
..anyone know the statement as above could be start at begining , so what is the (String[ ] args) mean in java ?
in my ideas of this statement is
publc : indicates the statemean can be used as all class , this is open for public use
static mean the main method can used as class method
void indicate that the statement return nothing
main indicate any class should be run this first.
so my question what is the function of (String [ ] args) ? // one string array call args ?

String[] args is indeed an array of Strings called args. The reason it's there is to collect any arguments passed to your code when you start it.
eg. if you have a class called TestClass and you called it from the command line like this:
java TestClass exam tomorrow oh shite
.......then the args array would hold the four Strings:
exam
tomorrow
oh
shite

Submitting a PDF form via HTTP Post: Beginner's Questions

Hi,
I am completely new to PDF forms, so I have been finding the documentation and options overwhelming.
I am hoping to get pointed to the documentation/tutorials/examples I really need.
I would like to build a "proof of concept" for my boss. I would like to include a screen in our Java ( JSP & Spring ) webapp where either a PDF form is embedded or is accessed via a link.
I have
Adobe Acrobat Distiller X standard license
Adobe Acrobat X Standard
Microsoft Office 2010
I made a small, 3 field Microsoft Word form. I then converted it via DIstiller into a PDF form.
I then found this document about how to submit a PDF form to a server side component:
http://acrobatusers.com/tutorials/form-submit-e-mail-demystified
My big problem with this document it doesn't have an example nor an example showing what is going on in a full HTML page. As I result I have some questions:
Can I see such an example somewhere?
Does the call to the javascript function doc.SubmitForm(urlToMyServerSideComponent) go in a script tag on the HTML page like other javascripts?
Can I execute that submit function from an HTML button or do I need to put a "submit" button on the PDF form?
Do I need Adobe LiveCycle in order to create a PDF form with a "submit" button? Free versions?
Can I send via HTTP POST ?
Do I need Adobe LiveCycle to crate a PDF form with a digital signature?
Is there a document/tutorial that fits where I am starting off from? ( Please no books, I am tyring to show my boss that this is something that can be done, in a reasonable amount of time, not time to get and go through a book ).
Thanks in advance for any tips that get me pointed in the right direction
Steve

To answer some of your specific questions:
2, 3. The submit form button needs to be on the PDF. You can either configure a Submit Form action or use the submitForm JavaScript method.
4, 6: No to both questions. You can create the form in Acrobat. Such forms are knows as Acroforms, as opposed to XFA forms that are created with LiveCycle Designer. Acroforms have wider support.
5: Yes, that's the method that's used when submitting to a web server. You have your choice of formats. The "HTML Form" option causes the form data to be submitted in the same format as an HTML form, so the same type of server-side code can be used to process the data. As Dave's tutorial shows, the server should return an FDF as the response, however, as opposed to HTML content.
It's a mistake to try to embed the PDF in a web page. So much depends on the user's browser, PDF viewer, and how both are configured. PDF forms can be submitted directly from Adobe Reader/Acrobat, so it's not necessary for them to be viewed in a browser. Note that Adobe Reader for iOS/Android don't yet support submitting to a web server (apart from FormsCentral), but that's is supposedly being worked on.
Since you mentioned digital signatures, be aware that for Reader users to be able to sign, the document has to be Reader-enabled, either with Acrobat Pro or LiveCycle Reader Extensions (which is not the same as LiveCycle Designer). Digital signatures in PDF forms are not yet supported on mobile devices. Also, you will want to submit the entire PDF, as opposed to just the form data, when submitting a digitally signed form.

Forte for Java question

By using the JDBC form wizard, I generated a swing program. Along with the java code, there is a form file which looks like an xml file. My question is how to complie and run the java source code without a forte4j IDE?
Thanks

One thing is you need the jdbc in your classpath or specify at runtime. Search compiler in the forte help menu - to see options.
execution : <specify at runtime>
java -classpath:.;postgresql.org Program
-- above for postgresql driver residing in same directory as Program.class
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Ray

TextSamplerDemo.java question

I took the TextSamplerDemo from http://java.sun.com/docs/books/tutorial/uiswing/components/text.html and stripped it down to the one thing I have a question about. Given the code below, how do I implement the toolbar button to make selected text turn bold? I've been beating my head againt this one for a couple of days now and getting nowhere.
Any help would be deeply appeciated.
--gary
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import javax.swing.text.*;
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import java.awt.event.*; //for action events
public class TextSamplerDemo extends JPanel
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private String newline = "\n";
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paneScrollPane.setVerticalScrollBarPolicy(
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paneScrollPane.setMinimumSize(new Dimension(10, 10));
add(textPane);
public void actionPerformed(ActionEvent e) {
private JTextPane createTextPane() {
String[] initString =
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String[] initStyles =
{ "regular", "italic", "bold", "small", "large",
"regular", "regular"
JTextPane textPane = new JTextPane();
StyledDocument doc = textPane.getStyledDocument();
addStylesToDocument(doc);
try {
for (int i=0; i < initString.length; i++) {
doc.insertString(doc.getLength(), initString,
doc.getStyle(initStyles[i]));
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//Initialize some styles.
Style def = StyleContext.getDefaultStyleContext().
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Style regular = doc.addStyle("regular", def);
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s = doc.addStyle("bold", regular);
StyleConstants.setBold(s, true);
s = doc.addStyle("small", regular);
StyleConstants.setFontSize(s, 10);
s = doc.addStyle("large", regular);
StyleConstants.setFontSize(s, 16);
private JToolBar buildToolbar() {
JToolBar toolBar = new JToolBar();
toolBar.setRollover( true );
toolBar.setFloatable( false );
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boldButton.setToolTipText( "Set selected text to bold" );
boldButton.addActionListener( new ActionListener() {
public void actionPerformed( ActionEvent e ) {
// code here to make selected text bold
toolBar.add( boldButton );
return toolBar;
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
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//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
JFrame frame = new JFrame("TextSamplerDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
JComponent newContentPane = new TextSamplerDemo();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
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frame.pack();
frame.setVisible(true);
public static void main(String[] args) {
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//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
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try this, but im'not sure.
StyleContext styleContext = StyleContext.getDefaultStyleContext();
Style def = styleContext.getStyle(StyleContext.DEFAULT_STYLE);
Style bold = styledDocument.addStyle("bold", def);
StyleConstants.setBold(bold, true);into the listener of your component insert this:
int start = getSelectionStart();
int len = getSelectionEnd() - start;
styledDocument.setCharacterAttributes(start, len, bold, true);by gino

EDID and LUT - a java question

Hi all!
I just got my Mac Mini two days ago. I need some help in accessing certain informations to a java app I'm ought to write. I tried to google 'em up, but I got stuck. Maybe someone here could help me?
1. How can I get EDID from my display? I've seen there's something called read-edid under linux, but I don't really know how close a relative Tiger is to linux/BSD.
2. How can I write to LUT on my Mac?
I suppose there are some libraries, that I can use, but I can't find them
If not, maybe someone could direct me to a C library, so I can hopefuly run it via JNI.
Any help would be greatly appreciated.
TIA,
Pablo

blue-rose wrote:
i don't see someone who want to help me =/ ,, if u don't want to ,, it's up to you ,, but there is no need for these words which u said to me ,, it really hurts ,, thanks all anyway =( ,,Seriously though, we help those that show that they are willing and able to do some work first. All you've posted was a classic "homework dump", and these are the typical responses to homework dump questions. Lesson learned.

Beginner Java questions

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