Easy question about String

Hi!
I have a string in a variable. how can I check if the String is composed just by numbers?
thank you very much!

Use the following method from Integer API
parseInt
public static int parseInt(String s)
throws NumberFormatExceptionParses the string argument as a signed decimal integer. The characters in the string must all be decimal digits, except that the first character may be an ASCII minus sign '-' ('\u002d') to indicate a negative value. The resulting integer value is returned, exactly as if the argument and the radix 10 were given as arguments to the parseInt(java.lang.String, int) method.If it throws NumberFormatException its alphanumeric else its numeric. You would however have to remove any spaces or commas etc. since they are not mumeric either

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Easy question about Reformatting

Hello all,
I am trying to reformat my HD after I have deleted Windows XP off of a partition. The reason for this is an upgrade to Vista and a larger allotment of HD space. My question is:
I am using Backup v3.1.1. (v369) and I have FULL backup files of my Home folder, and my Music folder (as backup for my backup) for all my iTunes libraries. These are located on a portable HD. Are these the correct files to have backed up in order to have my MAC the way it was before I started the process? If so, then once the reformatting is complete, how do I get it all back onto my MAC permanently? Will all my apps and tweaks work as before?
I am sure this is a simple question, however, I have never had to do this with a MAC, and I want to make sure I have all bases covered before I begin this. Any other comments or advice would be greatly appreciated.
Thanks All!

You call this an easy question ???
Just messin with ya
Your home folder is the most important folder containing your music, documents, preferences etc. but a lot is also stored in the system folder and library folder outside your home folder, if you want to be ensured of an exact copy of your current system the best way to go at this is to clone your system partition.
The app i use for this is carbonCopyCloner
http://www.bombich.com/software/ccc.html
To add to this.. i've heard there is software for the mac that allows you to make adjustments to the size of your partitions without having to format the drive, i don't know the names of these products but i do know that it's very risky to use them, if you decide to use an app like that make sure you have proper backups of everything just in case it goes wrong.
Message was edited by: Pr0digy V.

A question about string.trim()

I got a fragment of code as follows:
String s = "abcd ";
boolean a = (s.trim()=="abcd");
boolean b = (s =="abcd ");
Why a is false, b is true?

The reason why the below code has true assigned to be is quite easy to explain:
String s = "abcd";
String y = "abcd";
boolean b = (s == y);
...The String class has a "Pool" of strings. When you use String literals; the compiler automatically checks if it is in the String pool already and if it exists; a reference to that String is returned; if not a new entry in the pool is added and then you get a reference to that. This is only true for Stirng literals and String created using the intern() method.
If you compile this code you will see that the strings are not equal:
public static void main(String args[])
String s = "abcd";
String y = args[0];
boolean b = (s == y);
System.out.println(b);
}This is because the "abcd" is in the String pool when your program starts; but because the value "abcd" passed in (is not created in the pool automaticlaly). Therefor they are two different String objects.
This code block shows that you can add Strings to the pool. The intern() method checks to see if the String is in the pool already and if it is it will return you a reference to it; if not it will create one and then return it.
public static void main(String args[])
String s = "abcd ";
String y = args[0].intern();
boolean b = (s == y);
System.out.println(b);
}- Chris

Easy question about checking a string

hi guys i have a problem that im sure most of you will know and im probably doing something silly, I have a record and am wanting to check the values in some fields so i have:
IF Rec1.next_record = 'Renault' AND Rec1.prev_record != 'Vauxhall'
the != part doesnt seem to be working, should i be using a different method to check if the string is not equal to the given text?
Thanks.

thats the problem then, the value is null, so you would think if i done
if Rec1.prev_record = NULL it should work? though it doesnt appear to. Would you have any ideas on that?
Thanks for the information, quite helpfull.

Easy Question about resizing video

I searched 'Resizing Video' and there was too many unrelated results to a really simple question.
In my old program "Premiere', to resize and move a video around was very easy. You could adjust the scale and X-Y values numerically, or you could use a Free Transform like in Photoshop. Simply dragging bounding boxes for size and aspect and also dragging the clip to decide it's location.
The only way I know how to do this in FCP is I double click a clip in the sequence, it loads into the viewer, I go to the Motion Tab and then I can adjust the Scale, which is cool. But then I'm left with the Distort section to adjust position (and aspect if need be). In the Distort section there are 8 numeric fields of info to figure out and fill out just to get one clip in a different position correctly.
I'm thinking there must be another way to adjust the location (or aspect) of a video clip without spending a bit of time on exact coordinates, I want to eye-ball where I want the clip to go and simply move it there. Is the Distort feature the only way to do this? If not, which is the fastest way to move and change the dimension of a clip.
Thanks for reading, I hope there is another way, I'm not use to these calculations and they're slowing me down.
Monty

I searched 'Resizing Video' and there was too many unrelated results to a really simple question.
That's because it's not a simple question at all and yet every one of those threads was related to the OP's question. As you discovered, there are lots of ways to interpret "resize," during capture, editing, effects, output, viewing, encoding, printing. But the solution was even simpler than you thought. All you had to do was open the manual or the online help system. Start taking the manuals to the gym with you. FCP is not Premiere. You're going to hate FCP, you're going to love FCP but it will never behave like Premiere beyond the elements of the functional paradigm. Forget Premiere.
bogiesan

Easy question about JScrollPane issue

The problem is I do not understand why it is not possible, or what I am doing wrong to not be able to initialize a JScrollPane with a variable and call it later, real easy to see in the code below.
NOTE! I CAN use scrollbars, but only without initializing first, am just trying to understand how to properly do this with initialization or if it is not possible.
Thank you!!!!
just look for the First 3 commented sections with stars ******
import java.awt.Container;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class SquareIntegers extends JApplet {
     // set up GUI and calculate squares of integers from 1 to 10
     public void init() ///all variables below are LOCAL, because used only in "init()" if needed elsewhere make above in the CLASS
                         //OR SAVE VALUES between calls to the class's methods
          // get applet's content pane (GUI component display area)
          Container container = getContentPane();
          container.setLayout(new FlowLayout());
          //creaing a layout because I wanted to add a scroll pane
          //container.setLayout(new BorderLayout());
          // JTextArea to display results
          JTextArea outputArea = new JTextArea(8, 8);
          // JScrollPane myscrollbar = new JScrollPane( outputArea ); //********************this is line 27 why does this along with line 33 NOT work????????
          // attach outputArea to container
          container.add( outputArea);
          //container.add( myscrollbar); ******************************this is Line 33 why does this along with line 277 NOT work????????
          container.add(new JScrollPane( outputArea ));//***********this is Line 34, if I comment out 27/33, and just use this, scrollbars
                                                                 // work correctly, but I have heard/seems better to "initialize variables first"
          int result; // store result of call to method square
          String output = ""; // String containing results
          // loop 10 times
               for ( int counter = 1; counter <= 10; counter++ ) {
               // calculate square of counter and store in result
               result = square( counter );           //***********************uses the CUSTOM method from line 44
               // append result to String output
               output += "The square of " + counter +
               " is " + result + "\n";
               } // end for structure
     outputArea.setText( output ); // place results in JTextArea
} // end method init
     // square method definition...***** This is a CUSTOM method creation..... if "Math.sqrt" was used, we would not have to do this
     public int square( int y )
     return y * y;      // return square of y this is RETURNED to the statement in "init()" that originally invoked the
                         // "square()" method - in this case line 32, where RESULT invoked the METHOD, so "result" gets the value of RETURN
                         // if it were "public int square()" that means the method does NOT return a value
The general format of a method definition is
return-value-type method-name( parameter-list )
declarations and statements
including "return;" or "return EXPRESSION;"
     } // end method square ALL METHODS must always be created inside the CLASS definition, as this one is... notice the closing
          // CLASS bracket below
} // end class SquareIntegers

Thank you!!!
I think I understand...... since the JScrollPane already assigned itself to the JTextArea....
when "adding" to the parent container, the only necessary component to call was in fact the JScrollPane with the container.add( myscrollbar); I do not know if this is correct, but I thank you for your help, because this definitely confused me, back to studying :)
I have it 100% operational, just posting this to say thank you that it worked, and it will help further my and possibly others understanding of this.

Question about string manipulation

Hello, I am practicing with Java and trying to learn it, and have a quick question. I am trying to get the count on a string of numbers for after a decimal point. the numbers are generated as the result of a math, so I can't use index, since the location of the decimal changes based on the number imputed. I want to figure this out on my own, but have hit a wall here, i've spent the past few hours trying every string command I can think of, and haven't figured it out yet, anyone mind pointing me in the right direction for which string to use? Thanks in advance for any help you can provide!

Is this what you want?
public class Fallen{
public static void main(String[] args){
    String number = "123.45678";
    String frac = number.substring(number.indexOf('.') + 1);
    System.out.println(frac + " length=" + frac.length());
    frac = number.replaceFirst("^.+\\.", "");
    System.out.println(frac + " length=" + frac.length());
}

Very easy question about variables

Can I convert float-variable to String-variable?

Hi, a very easy way to convert almost anything is
called "typecasting". It might sound difficult, but
it isn't.
You use it like this example
> String outcome;
Double input;
input = 3.54789654587;
Output = ""+input;
That's not casting. It's implicit formatting.
What it does is making an empty string and pasting
your number behind it. VERY easy! You can do this
with allmost every type of variables.What it's doing is creating a StringBuffer, appending an empty string to it, then appending the result of calling toString on the Double, which is itself a String. (Though things change a bit in jdk1.5.) It works because StringBuffer.append has versions for each primitive type, and toString exists for all Objects.
One problem is that it's not efficient -- you're doing a lot of work behind the scenes to do something that can be done much more simply. But the bigger problem is that it's using operators in a roundabout way and with implicit results. So it's sort of a hack. "+" is the append operator for Strings (well it actually comes down to an implicit method call, or several). Putting the double on the right side of that also causes an implicit format. So you're implicitly formatting a value, and then appending it to nothing, to get a result. You're not actually meaning to append, you're meaning to format, but you're using an append operator.
The more straightforward way to do it is simply to explicitly format it, using the methods already shown on this thread, or using java.text.DecimalFormat.

Quick (hopefully easy) question about rotating video...

I'm going to be shooting some video soon that I will later be editing with FCP. I'm going to shoot the video on a Canon Vixia HF10 (AVCHD) camcorder.
In the situation I'll be shooting, with the mount I'll be using, it would be much easier for me to shoot this video with the camera fully upside-down.
If I shoot the video fully upside down, can I easily rotate it 180 degrees in FCP with no loss of quality?
Thanks!

An interesting thing about video that is shot upside down is the ballistics of the camera movement can be weirdly disconcerting. For instance, if it's a helmet- or wing-style mount, pans and tilts just feel odd.
As Eric suggests, flipping the image 180 degrees is easy but practice and evaluate.
bogiesan

Quick Easy Question About N580GTX-M2D15D5 Bios

Hey guys!!
I just have a real quick and easy (i suppose) question!
I had bios version KH0, and MSI live update found KH1, i downloaded and flashed successfully (DOS window said please restart and press any key to exit) so i did, restarted my computer, and MSI live update utlity and gpu-z and MSI afterburner are all reporting the same bios version i had with the KH0, version 70.10.17.00.01 & date November 09, 2010
MSI live update is not picking up the update again, so my question is, how do i know if it flashed correctly since the bios date and version remained the same?
Thanks !

Quote
I had bios version KH0, and MSI live update found KH1, i downloaded and flashed successfully (DOS window said please restart and press any key to exit) so i did, restarted my computer, and MSI live update utlity and gpu-z and MSI afterburner are all reporting the same bios version i had with the KH0, version 70.10.17.00.01 & date November 09, 2010
Quote
version 70.10.17.00.01
that's suppose to be, this is the version of the both bioses
Quote
& date November 09, 2010
this is GPU release date, not BIOS date
Quote
MSI live update is not picking up the update again, so my question is, how do i know if it flashed correctly
Get this: https://forum-en.msi.com/index.php?action=dlattach;topic=147603.0;attach=7931
extract it somewhere, then run info1 , and look for the last line
Quote
since the bios date and version remained the same?
they are not the same, your looking the wrong stuffs

Really easy question about DVDs

I am about to get a new 5g iPod, and I am excited about being able to watch videos on it. But I have a quick question, is it possible to rip DVDs(like you can with CDs) from iTunes?
Thanks

This article addresses your question:
http://docs.info.apple.com/article.html?artnum=302758

Easy question about parts of this code

Code: The purpose is to find a character in a string, and report how many times the character occurs in the string. Basically the program does looking and counting. The code is complied and working well, but my goal is to make it as short as possible, if you can just write a program does the same job in no more than five lines, i will be very appreciate if you share your idea with me.
public class CharFinder{
public static void main(String args[])throws java.io.IOException{
String content;
char target;
int fromIndex = 0;
int foundIndex;
int count = 0;
content =("hello world, i am a boy, and i need help.");
System.out.print("Enter the character to be counted: ");
target = (char)System.in.read();
for (int i=0;i<=content.length()-1;i++)
foundIndex = content.indexOf(target, fromIndex);
if (foundIndex >= 0)
count++;
fromIndex = foundIndex + 1;
System.out.println(" '" + target + "' occurs " + count + " time(s)");
Question:
1.what does string.indexOf do?
2. what are fromIndex and foundIndex 's jobs in the code? in another word, what are they doing in the code?
3. I have to put it in a method, like public void charFinder(), but it cannot compile cuz of throws java.io.IOException, the compiler always says it needs ; at the end..........i can't understand the problem.
Thank you so much if you can answer them.

I think the from index counts how many letters are from the index... and the found are the letters that were found, and the +1 tells it to go on to the next letter to see if it should send that letter back to you.... your third question, the compilers always say you need stuff, adn when you find a problem it has ntohing to do with what it says... my suggestion is just look for something that might be out of place.

Need help! easy question about scrollpane?

DefaultStyledDocument document = new DefaultStyledDocument();
JTextPane tp = new JTextPane(document);
tp.setMargin(new Insets(5,5,5,5));
JScrollPane tpScrollPane = new JScrollPane();
tpScrollPane.setBounds(new Rectangle(5,5,100,200));
tpScrollPane.getViewport().add(tp, null);
the compile and run are both OK. but i found it quite strange that the vertical scroll bar works well while the horizental scroll bar doesn't work. when the string inputed up to the width, more inputted characters will be showed in a new line. Could anyone have the same experience and know how to solve it?
any suggestions are appreciated!
thanks in advance!

have you tried it using
tpScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS;

Easy question about install time

Hello,
I have been having a lot of problems with my MacBook and after posting on the forums it seems a re-install might help. This is my firt time doing a wipe/install so I backed up my files and booted from my Tiger install DVD and did a wipe/install and I am staring at in installing right now. It seems to be taking forever! It has been going for about 2 hours now and is about 1/3 of the way finished and says it has 3 hours 43 minutes to go. Is it supposed to take this long?

Hi,
I haven't installed Tiger on an Intel Mac but have installed Jaguar, Panther and Tiger a number of times on PPC Macs. It never took more than 30 minutes to complete.
I would suggest you let the installation run its course and then see how the computer is working.
It might be that your HD needed repairing... did you check it with disk utility before starting the installation ?
One more thing... after the first boot (where you set up accounts,etc) you should boot from the install DVD check the disk with disk utility and repair if necessary.
S

Question about String constant pool

Is there is any function available to find how many Sring literal in String Constant pool

Well, there's stuff like BCEL.
But it may not do what you want.
Why do you want to find out what's in the constant pool?

Easy question about String

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