Sort array(list) of files on filename

Hey all,
Is there a way to sort an array(list) of files on the names of those files. (the files are not in same directory)
Thanks

Gogoe wrote:
Hey all,
Is there a way to sort an array(list) of files on the names of those files. (the files are not in same directory)
Thanks
Why do you need to sort the actual Files? Can't you just sort the list of name using Arrays.sort()? Once the names are in order you call up the Files in the order you read the names. Or is there more to the request yet?

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Sorting array list

can u please give me the source code for:
sorting array list for ascending and descending order

You already have the source code.

Sort array list and using comparable

With the following code I would like to setup a score object for the current player.
Change it to a string(Is it correct to say parse it to a string type)
Then add it to the arraylist.
So I can sort the array list according to the string size.
That's why I have the variables in that order.
So if 3 players have the same amount of guesses, they can be positioned on the high score list according to their gameTime.
//create score object
               Score currentScore = new Score(guessCount, gameTime, name);
               String currentScoreToString = currentScore.toString();
               //add score to arrayList
               scores.add(currentScoreToString);So the error message says " The method add(Score) in the type arrayList <Score> is not applicable for the arguments(string)"
Now, I understand that, I would like to know if there is another way to achieve what I am trying to do.
Is the string idea I am trying here possible? is it practical or should I use comparable?
I have looked at comparable, but I don't get it.
Will my Score class implement comparable. I am looking at an example with the following code.
Employee.java
public class Employee implements Comparable {
    int EmpID;
    String Ename;
    double Sal;
    static int i;
    public Employee() {
        EmpID = i++;
        Ename = "dont know";
        Sal = 0.0;
    public Employee(String ename, double sal) {
        EmpID = i++;
        Ename = ename;
        Sal = sal;
    public String toString() {
        return "EmpID " + EmpID + "\n" + "Ename " + Ename + "\n" + "Sal" + Sal;
    public int compareTo(Object o1) {
        if (this.Sal == ((Employee) o1).Sal)
            return 0;
        else if ((this.Sal) > ((Employee) o1).Sal)
            return 1;
        else
            return -1;
ComparableDemo.java
import java.util.*;
public class ComparableDemo{
    public static void main(String[] args) {
        List ts1 = new ArrayList();
        ts1.add(new Employee ("Tom",40000.00));
        ts1.add(new Employee ("Harry",20000.00));
        ts1.add(new Employee ("Maggie",50000.00));
        ts1.add(new Employee ("Chris",70000.00));
        Collections.sort(ts1);
        Iterator itr = ts1.iterator();
        while(itr.hasNext()){
            Object element = itr.next();
            System.out.println(element + "\n");
}The thing I don't understand is why it returns 0, 1 or -1(does it have to do with the positioning according to the object is being compared with?)
What if I only use currentScore in a loop which loops every time the player restarts?
//create score object
               Score currentScore = new Score(guessCount, gameTime, name);
               String currentScoreToString = currentScore.toString();
               //add score to arrayList
               scores.add(currentScoreToString);Also why there is a method compareTo, and where is it used?
Thanks in advance.
Edited by: Implode on Oct 7, 2009 9:27 AM
Edited by: Implode on Oct 7, 2009 9:28 AM

jverd wrote:
Implode wrote:
I have to hand in an assignment by Friday, and all I have to do still is write a method to sort the array list. Okay, if you have to write your own sort method, then the links I provided may not be that useful. They show you how to use the sort methods provided by the core API. You COULD still implement Comparable or Comparator. It would just be your sort routine calling it rather than the built-in ones.
You have two main tasks: 1) Write a method that determines which of a pair of items is "less than" the other, and 2) Figure out a procedure for sorting a list of items.
The basic idea is this: When you sort, you compare pairs of items, and swap them if they're out of order. The two main parts of sorting are: 1) The rules for determining which item is "less than" another and 2) Determining which pairs of items to compare. When you implement Comparable or create a Comparator, you're doing #1--defining the rules for what makes one object of your class "less than" another. Collections.sort() and other methods in the core API will call your compare() or compareTo() method on pairs of objects to produce a sorted list.
For instance, if you have a PersonName class that consists of firstName and lastName, then your rules might be, "Compare last names. If they're different, then whichever lastName is less indicates which PersonName object is less. If they're the same, then compare firstNames." This is exactly what we do in many real-life situations. And of course the "compare lastName" and "compare firstName" steps have their own rules, which are implemented by String's compareTo method, and which basically say, "compare char by char until there's a difference or one string runs out of chars."
Completely independent of the rules for comparing two items is the algorithm for which items get compared and possibly swapped. So, if you have 10 Whatsits (W1 through W10) in a row, and you're asked to sort them, you might do something like this:
Compare the current W1 to each of W2 through W10 (call the current one being compared Wn). If any of them are less than W1, swap that Wn with W1 and continue on, comparing the new W1 to W(n+1) (that is, swap them, and then compare the new first item to the next one after where you just swapped.)
Once we reach the end of the list, the item in position 1 is the "smallest".
Now repeat the process, comparing W2 to W3 through W10, then W3 to W4 through W10, etc. After N steps, the first N positions have the correct Whatsit.
Do you see how the comparison rules are totally independent of the algorithm we use to determine which items to compare? You can define one set of comparison rules ("which item is less?") for Whatsits, another for Strings, another for Integers, and use the same sorting algorithm on any of those types of items, as long as you use the appropriate comparison rules.Thanks ;)
massive help
I understand that now, but I am clueless on how to implement it.
Edited by: Implode on Oct 7, 2009 10:56 AM

Sort Array List

Hi,
I have an array List which have values like empid, amount, corpcode eg.
223, 345.95, SDB
791, 567.75, XYZ
115, 345.95, SDB
I need to sort this array like this
115, 345.95, SDB
223, 345.95, SDB
791, 567.75, XYZ
How can I do this?
Thanks

You have to implement a natural order for your object, so that it can be sorted. There are a lot of tutorials out there for this, but I will do it anyway for you:
public YourClass implements Comparable<YourClass>{
int firstNumber;
int secondNumber;
int thirdNumber;
String someIdentifier;
public int compareTo(YourClass otherObject){
   int difference = this.firstNumber - otherObject.firstNumber;
   if(difference != 0) return difference;
   difference = this.secondNumber - otherObject.secondNumber;
   if(difference != 0) return difference;
   return this.someIdentifier.compareTo(otherObject.someIdentifier);
}As you can see, the basic idea is, that you return if an object is greater, equal or less than another. You begin with the most important criteria. If this one is equal, you check the next one.
Some objects already include the comparable interface, like String. If this is the case, you can take advantage of this, and use their compareTo Method.
After this, you can sort your objects with
Collections.sort(someList);

How to write array list to file ?

Hi everyone,
I got a arraylist binaryEncodedData and I want to write to file. how do I make it into a HexString ? I had tried to convert it this way and it doesn't work. I try to print out the temp value but there was nothing . Please help, thanks
byte[] bytes = new byte[binaryEncodedData.size()];
String temp;
for(int i=0;i<binaryEncodedData.size();i++)
     bytes[i] = (byte)binaryEncodedData.get(i);
for(int i=0;i<bytes.length;i++)
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Strings are immutable. The correct way to get anything to print out is this:
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I'm having problems coding these two methods... Could someone explain how to do this? I can't find information on it anywhere... :(
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Then,
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Operating on a list of files with spaces in the filenames

I am writing a script that operates on all files within a directory structure. I want to pass the full filename and path to the commands in the script. I am using a for loop to do this. Unfortunately, I don't know how to get the "for" line to pass this info properly.
I have the following items on the desktop:
a folder with a lot of spaces in its filename
file1
file2
file3
If I run
for i in $( find * /Users/<username>/Desktop/ ) # where <username> = the correct shortname
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folder
with
a
lot
of
spaces
in
its
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Desktop/file1
Desktop/file2
Desktop/file3
If I run:
for i in "$( find * /Users/<username>/Desktop )"
I get every full path for each file on the Desktop, but they're all run together on a single line as below:
Desktop/a folder with a lot of spaces in its filename Desktop/file1 Desktop/file2 Desktop/file3
How do I get the following output?
Desktop/a folder with a lot of spaces in its filename
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Desktop/file2
Desktop/file3

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[[ "$file" = .app/ ]] && continue
echo "$file"
done
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split

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I'd appreciate it if someone could take a look at my code and give me some ideas on what my problem might be.
Thanks in advance! (note: I also posted this question to java-forums.org, as I've been working on this little problem for over five hours and am in desperate need of some help!)
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right[i] = names[i + names.length/2];
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mergeSort(right);
merge(names, left, right);
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// post: result contains result of merging sorted lists;
// add merge method below
public static void merge(String[] names, String[] left, String[] right)
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int i2 = 0;
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Welcome to the forum.
Please read this to learn hot to format your code (and other things relevant for this forum):
https://forums.oracle.com/forums/ann.jspa?annID=1535
923566 wrote:
Hi, I'm trying to sort a list of names alphabetically, case-insensitive by using the mergesort technique.
I wrote this codeDo you know the <tt>TreeSet</tt> class?
http://docs.oracle.com/javase/7/docs/api/java/util/TreeSet.html
With that sorting Strings is a two liner:
http://www.java2s.com/Code/Java/Collections-Data-Structure/TreeSetDemo.htm
bye
TPD

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I had too many problems with printArray() so I figured this could be easier.
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Is there a way that you can get a list of files in a directory that are spelt a certain way? Ex. If in a directory there are html files, txt files, et, In java can I get *.html or a html file with certain text in the name? java.html??
How you can Help
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here are the code to list your files
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Dear all,
I got a question about directory listing and file creation. My development OS is Win2K traditional chinese version and my JDK is 1.4.0 Internationation version.
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ArthurPan

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I'm making a mock up of iTunes, I suppose, for class. My only issue is that I can't figure out how to add all the durations of each sound file when it's stated in the array.
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import java.applet.*;
import java.io.*;
import java.net.*;
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import java.util.Iterator;
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     * Extra Credit
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        Iterator<Sound> iter = playlists.iterator();
        while(iter.hasNext()) {
            ((Sound)iter.next()).playSound();
}

not sure if I'm missing something here, but this could possibly be solved by initializing a variable to 0 before the for loop, and then adding each duration to this variable as you loop. This seems too trivial a solution though. Again, I may be missing something here.
something simple like:
public void calcSum()
    int i = 0;
    for(Fubar foo: fooList) {
        i += foo.getLength();
    System.out.println("Sum = " + i);
}Edited by: petes1234 on Oct 23, 2007 9:09 AM

Sort array(list) of files on filename

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