Identical random sort for 2 arrays

Hi,
I got this function, which is sorting my array in a random way.
private function randomSort(objA:Object, objB:Object):int {
return Math.round(Math.random() * 2) - 1
arr.sort(randomSort);
I need to shuffle another array, but I need it to have exactly the same random order as the first one. If I use the same funcition:
arr2.sort(randomSort);
I will get different order in both arrays.
Is there a possiblility to randomize two arrays in the same order?

you're not randomizing array elements because:
1. you probably don't want a uniform distribution of -1,0,1. you probably only want to return 0, if the array elements are the same.
2. if you do want a uniform distribution of -1,0,1:
n = Math.round(Math.random() * 2) - 1
won't give it to you: n=0 (1/2 the time), n=-1 (1/4 the time), n=1 (1/4 the time)

Similar Messages

TreeSet vs Collection.Sort / Array.sort for Strings

Gurus
I am pondering weather to use TreeSet vs the Collections.sort / Array.sort for sorting Strings.
Basically I have a list of Strings, i need to perform the following operations on these Strings
1) Able to list Strings starting with a Prefix
2) Able to list Strings Lexically greater than a String
Any help would be greatly appreciated!
Thanks a bunch

SpaceShuttle wrote:
Gurus
I am pondering weather to use TreeSet vs the Collections.sort / Array.sort for sorting Strings.
Basically I have a list of Strings, i need to perform the following operations on these Strings
1) Able to list Strings starting with a Prefix
2) Able to list Strings Lexically greater than a String
Any help would be greatly appreciated!
Thanks a bunchBig-O wise, there's no difference between sorting a list of N elements or inserting them one by one in a tree-set. Both take O(n*log(n)). But both collections are not well suited for looking up string that start with a certain substring. In that case you had better use a Patricia tree (or Radix tree).
Good luck.

Randomly Sort array of integers

All,
I have a question. I am writing an applet that loads a bunch of images into an array and then draws all the images in the array. However,I want to be able to randomly shuffle the images in the array and print them out.
I can randomly do this with numbers but how would I do it for a array of images?
Thanks

Here's something I use for shuffling object arrays: public class Shuffler {
    static private final Random RNG = new java.util.Random() ;
    static public void shuffleObjects(Object[] objs) {
        int offset = 0 ;
        int cnt = objs.length ;
        while (cnt > 1) {
            int swapIdx = RNG.nextInt(cnt) + offset ;
            if (swapIdx != offset) {
                Object tmp = objs[swapIdx] ;
                objs[swapIdx] = objs[offset] ;
                objs[offset] = tmp ;
            offset++ ;
            cnt-- ;
}

Sorting Methods for an Array

I'm trying to sort an object array of bank accounts based on their balance. JGRASP doesn't like my calling statement, which I don't think is correct.
My question is am I calling the method correctly (trying to set the bankArray[counter].getBalance()) and am I using the sort method correctly?
my call method
bankArray = bankArray[counter].selectionSort(bankArray[counter].getBalance(), counter);My sort method:
public static void selectionSort (double [] sort, int length)
for (int i = length; i < 1; i--)
double currentMax;
int currentMaxIndex;
currentMax = sort[0];
currentMaxIndex = 0;
for (int j = 1; j < i; j++)
if (currentMax < sort[j])
currentMax = sort[j];
currentMaxIndex = j;
}//End if
}//End for

There are some points to notice:
Point 1: Your method receive an array of double and an int, as you passing a double and an int.
Point 2: Your algorithm doesn't work properly. First of all, the selection sort works by selecting the smallest unsorted item remaining in the list, and then swapping it with the item in the next position to be filled. Also, note that you don't swap the array elements in any moment.
Point 3: In Java, your selectionSort method don't need to receive a parameter to inform the array length. The array itself already have that information ("myArray.length").
Point 4: About the call of your method, you made it as the selectionSort method returns an array of BankAccounts - Supposing that you represent a bank account through an BankAccount class and bankArray[i] is an array of [i]BankAccount objects. It's not true. As you can see, your selectionSort method returns void, or either, returns nothing.
Observing those 4 first points, we can re-write your selectionSort method like this
     public static void selectionSort(double[] numbers) {
            for (int i = 0; i < numbers.length - 1; i++)
              int minIndex = i;
              for (int j = i + 1; j < numbers.length; j++)
                if (numbers[j] < numbers[minIndex])
                  minIndex = j;
              double temp = numbers;
          numbers[i] = numbers[minIndex];
          numbers[minIndex] = temp;
Now, when I try to re-write the call, I noticed other important odd thing about your approach: The [i]selectionSort method was written to sort bankAccounts, but it receives an array of double values. Being thus, you must to previously create a double[] object filled with the accounts' balances and then sort it. But, once sorted, how can you return the balances to their proper account? There is no way to do it. You have to sort a bunch of BankAccount objects, instead of an array of balances...
An intuitive implementation of this sorting cound be something like that:     public static void selectionSort(BankAccount[] accounts) {
          for (int i = 0; i < accounts.length - 1; i++) {
               int minIndex = i;
               for (int j = i + 1; j < accounts.length; j++) {
                    double
                         currBalance = accounts[j].getBalance(),
                         minBalance = accounts[minIndex].getBalance()
                    if (currBalance < minBalance)
                         minIndex = j;
               BankAccount temp = accounts;
               accounts[i] = accounts[minIndex];
               accounts[minIndex] = temp;
I noticed form your call that the [i]selectionSort method boleng to the BankAccount class. Once this method is static, It's strongly recomended that you invoke this method in a static way (from the class, instead of from an object).
Here it goes a fictional BankAccount class and a TestBankAccount class. Read it, Run it, Study it, Understand it.
package help.sun.imbrium;
public class BankAccount {
     private double balance;
     private int number;
     public static void selectionSort(BankAccount[] accounts) {
          for (int i = 0; i < accounts.length - 1; i++) {
               int minIndex = i;
               for (int j = i + 1; j < accounts.length; j++) {
                    double
                         currBalance = accounts[j].getBalance(),
                         minBalance = accounts[minIndex].getBalance()
                    if (currBalance < minBalance)
                         minIndex = j;
               BankAccount temp = accounts;
               accounts[i] = accounts[minIndex];
               accounts[minIndex] = temp;
     public BankAccount(int number, double balance) {
          this.balance = balance;
          this.number = number;
     public double getBalance() {
          return balance;
     public void setBalance(double balance) {
          this.balance = balance;
     public int getNumber() {
          return number;
     public void setNumber(int number) {
          this.number = number;
     public String toString(){
          return "[Account #" + number + " balance: $" + balance + "]";
class TestBankAccount{
     public static void main(String[] args) {
          BankAccount[] accounts = {
               new BankAccount(1, 154.23),
               new BankAccount(2, 1554.23),
               new BankAccount(3, 15.3),
               new BankAccount(4, 854),
               new BankAccount(5, -4.79),
          System.out.println("Unsorted:\n\t" + arrayToString(accounts, " "));
          BankAccount.selectionSort(accounts);
          System.out.println("Sorted:\n\t" + arrayToString(accounts, " "));
     private static String arrayToString(Object[] objs, String separator){
          StringBuilder sb = new StringBuilder();
          for (int i = 0; i < objs.length; i++) {
               Object obj = objs[i];
               sb.append(obj.toString());
               if(i < objs.length - 1)
                    sb.append(separator);
          return sb.toString();

We need a "random" option for sorting images

I often need to randomly sort huge collections of images for web sites. This is a pain to use the "user sort" mode. Dragging and dropping is to slow.

I tried to make my onw order of pictures into a slide show,
but I do not find how to move them.
can you help me ?
thx
An

Desperate HELP with Random Numbes in an Array & Do / While

Please somebody help, I have been working this problem for over 7 days now and can't get it. I have tried everything from a while to a do while to this and that. I need to have an Array of 8 that when run will produce random numbers for output between 15 to 25. I CAN"T GET IT PLEASE HELP. I am new to JAVA and have done everything I can think of to resolve this. I even have purchased a new book and looked at every site trying to find a solution. PLEASE HELP! Here it is:
import javax.swing.*;
public class RandomArray{
public static void main (String [ ] args) {
JTextArea outputArea = new JTextArea ( );
int myArray [ ]; //array declaration
myArray = new int [ 8 ]; //allocating memory
String output = "Array values at initializatioon ";
output += "\nIndex\tValues";
for ( int i = 0; i < myArray.length; i ++)
output += "\n" + i + "\t" + myArray [ i ];
output += "\n\nArray values after assigning values within the range of 15 and 25";
do {( int i = 0; i <myArray.length; i++)
     while     myArray [ i ] = 15 + (int) (Math.random ( ) * 25);
output += "\n" + i + "\t" + myArray [ i ];}
outputArea.setText (output);
JOptionPane.showMessageDialog (null, outputArea,
"Array Value before and after",
JOptionPane.INFORMATION_MESSAGE);
     System.exit ( 0 );
The output that I need is in two columns one with the initial array 0-7 and the second should be random numbers 15-25. Please help, please

here you are :
import javax.swing.*;
public class RandomArray
public static void main (String [ ] args)
     JTextArea outputArea = new JTextArea();
     int       myArray [] = new int[8];
     String output = "Array values at initializatioon ";
     output += "\nIndex\tValues";
     for (int i = 0; i < myArray.length; i ++)
          output += "\n" + i + "\t" + myArray [ i ];
     output += "\n\nArray values after assigning values within the range of 15 and 25";
     for (int i = 0; i < myArray.length; i++)
          myArray [ i ] = 15 + (int) (Math.random ( ) * 10);
          output += "\n" + i + "\t" + myArray [ i ];
     outputArea.setText(output);
     JOptionPane.showMessageDialog (null, outputArea,
          "Array Value before and after",
          JOptionPane.INFORMATION_MESSAGE);
     System.exit(0);

Newbie trying to sort 2D string array

Dear all,
After read some book chapters, web sites including this, I still don't get the point.
If I have a file like,
1 aaa 213 0.9
3 cbb 514 0.1
2 abc 219 1.3
9 bbc 417 10.4
8 dee 887 2.1
9 bba 111 7.1
and I load into memory as a String[][]
here comes the problem, I sort by column 1 (aaa,...,bba) using an adaptation of the Quicksort algorithm for 2D arrays
* Sort for a 2D String array
* @param a an String 2D array
* @param column column to be sort
public static void sort(String[][] a, int column) throws Exception {
QuickSort(a, 0, a.length - 1, column);
/** Sort elements using QuickSort algorithm
static void QuickSort(String[][] a, int lo0, int hi0, int column) throws Exception {
int lo = lo0;
int hi = hi0;
int mid;
String mitad;
if ( hi0 > lo0) {
/* Arbitrarily establishing partition element as the midpoint of
* the array.
mid = ( lo0 + hi0 ) / 2 ;
mitad = a[mid][column];
// loop through the array until indices cross
while( lo <= hi ) {
/* find the first element that is greater than or equal to
* the partition element starting from the left Index.
while( ( lo < hi0 ) && ( a[lo][column].compareTo(mitad)<0))
++lo;
/* find an element that is smaller than or equal to
* the partition element starting from the right Index.
while( ( hi > lo0 ) && ( a[hi][column].compareTo(mitad)>0))
--hi;
// if the indexes have not crossed, swap
if( lo <= hi )
swap(a, lo, hi);
++lo;
--hi;
/* If the right index has not reached the left side of array
* must now sort the left partition.
if( lo0 < hi )
QuickSort( a, lo0, hi, column );
/* If the left index has not reached the right side of array
* must now sort the right partition.
if( lo < hi0 )
QuickSort( a, lo, hi0, column );
* swap 2D String column
private static void swap(String[][] array, int k1, int k2){
String[] temp = array[k1];
array[k1] = array[k2];
array[k2] = temp;
----- end of the code --------
if I call this from the main module like this
import MyUtil.*;
public class kaka
public static void main(String[] args) throws Exception
String[][]a = MyUtil.fileToArray("array.txt");
MyMatrix.printf(a);
System.out.println("");
MyMatrix.sort(a,1);
MyMatrix.printf(a);
System.out.println("");
MyMatrix.sort(a,3);
MyMatrix.printf(a);
for the first sorting I get
1 aaa 213 0.9
2 abc 219 1.3
9 bba 111 7.1
9 bbc 417 10.4
3 cbb 514 0.1
8 dee 887 2.1
(lexicographic)
but for the second one (column 3) I get
3 cbb 514 0.1
1 aaa 213 0.9
2 abc 219 1.3
9 bbc 417 10.4
8 dee 887 2.1
9 bba 111 7.1
this is not the order I want to apply to this sorting, I would like to create my own one. but or I can't or I don't know how to use a comparator on this case.
I don't know if I am rediscovering the wheel with my (Sort String[][], but I think that has be an easy way to sort arrays of arrays better than this one.
I've been trying to understand the Question of the week 106 (http://developer.java.sun.com/developer/qow/archive/106/) that sounds similar, and perfect for my case. But I don't know how to pass my arrays values to the class Fred().
Any help will be deeply appreciated
Thanks for your help and your attention
Pedro

public class StringArrayComparator implements Comparator {
int sortColumn = 0;
public int setSortColumn(c) { sortColumn = c; }
public int compareTo(Object o1, Object o2) {
    if (o1 == null && o2 == null)
      return 0;
    if (o1 == null)
      return -1;
    if (o2 == null)
      return 1;
    String[] s1 = (String[])o1;
    String[] s2 = (String[])o2;
    // I assume the elements at position sortColumn is
    // not null nor out of bounds.
    return s1[sortColumn].compareTo(s2[sortColumn]);
// Then you can use this to sort the 2D array:
Comparator comparator = new StringArrayComparator();
comparator.setSortColumn(0); // sort by first column
String[][] array = ...
Arrays.sort(array, comparator);I haven't tested the code, so there might be some compiler errors, or an error in the logic.

Sort and Object array of Arrays

Hi,
I have an object array that contains a String[] and an int[].
Object[String[], int[]]
The values in the Strings array must be in the same position in the array as those in the int array i.e
String [0] is the string representation of int[0].
Its for a bar chart.
That is all working beautifully.
Now however I want to sort the int array in descending order by the value of the ints in the array and thus the order or the String array has to mirror this.
I am using a comparator to do this but it just wont work. I'm sure this is the way but how should it look?
Has anybody got any ideas?
Thanks in advance,
L.

use the bubblesort:
    for (int i = a.length; --i >= 0; ) {
        for (int j = 0; j < i; j++) {
            if (a[j][1] > a[j+1][1]) {
                int temp = a[j];
                a[j] = a[j + 1];
                a[j + 1] = temp;
    }

What types of sort performed by sort method of Array class ?

I use normal bubble sort and method Array.sort() to sort some given data of an Array and then count the time.But Array.sort() method takes more time then normal bubble sort.
Can anybody tell me what types of sort performed by sort method of Array class?

I'm pretty sure that in eariler versions (1.2, 1.3
maybe?) List.sort's docs said it used quicksort. Or I
might be on crack.You are actually both correct, and wrong :)
From the documentation of the sort methods hasn't changed in 1.2 -> 1.4 (as far as I can notice), and the documentation for sort(Object[]) says (taken from JDK 1.2 docs):
"This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.
The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). This algorithm offers guaranteed n*log(n) performance, and can approach linear performance on nearly sorted lists."
So, how could you be correct? The documentation for e.g. sort(int[]) (and all other primities) says:
"Sorts the specified array of ints into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance."
Your memory serves you well :)
/Kaj

Random order for a slide show?

How do you select a random order for a slide show?

You rang?
I had actually started working on this sometime in the past when this question was asked before. I never got around to finishing it but I cobbled this together this AM:
set newList to {}
tell application "Aperture"
activate
          set imageSel to (the selection)
          if imageSel is {} then
                    error "Select images."
          else
                    repeat until (count of newList) = (count of imageSel)
                              set randomPick to random number from 1 to (count of imageSel)
                              if randomPick is not in newList then set newList's end to randomPick
                    end repeat
                    repeat with i from 1 to count of newList
                              tell item i of imageSel to make new custom tag with properties {name:"Random", value:item i of newList}
                    end repeat
          end if
end tell
Takes a selection and assigns random numbers to each image in the selection,
Creates a custom tag Random and populates it with numbers. If you add the custom field Random to the list view metadata parameters you can sort on it and then switch back to icon view and the images will remain in the random order.
You have to be careful if you change the sort order of course the randomness will be gone and you will need to go back to list view to re-establish it.

Sort an String Array

Im having trouble sorting an Array. Before i add my new post to a[0] I would like to push all values one step. So value of a[0] will be stored in a[1] and value of [1] will be stored in [2] before a[0] = new value.
I haven found a way yet, anyone else?
Sebastian Green

Hmm, I worked my own way of handle it. Like this:
for (int i=4; i >= 0 ; i--) {
               if (i==0){
                    a[i] = getNewData();
               } else {
                    a[i] = a[i-1];
             }Which one is best? I could set the "int=4" dynamiclly . But why should I use Vector? I thought that it would be better with a String[]. Then I have set the amount of memory to use for my Array? Or is is better to store it in an Vector and call New Vector () every round so the size dosent get large then it has to?

Random sort order in slideshows

I was trying to import some jpg's into a slideshow, from a folder of jpg's. I found that the slides that ended up in the iDVD slideshow were randomly sorted. The sort order matched neither the date/timestamp, the filename, or any other metadata I could work out. I then imported them into iPhoto and discovered I could force a sort order there and bring them across from iPhoto into iDVD and that worked.
However, the behavior of iDVD when importing from a regular folder of images is very buggy, and of course there are no slideshow sorting options within the program. I do this regularly and pumping everything through iPhoto just so I can get my slideshows sorted is cumbersome. Has anyone else seen this and is there an explanation/fix?
Thanks.

Did you have any luck with this? I have been trying all day to find a solution for this very problem. I know I can do the *into iPhoto first* theory - but as I am adding from Aperture I had thought I was past the iPhoto malarky.

About the sort method of arrays

Hi,
I found that for primitive types such as int, float, etc., algorithm for sort is a tuned quicksort. However the algorithm for sorting an object array is a modified merge sort according to the java API. What is the purpose of using two different sorting strategy?
Thanks.

The language knows how to compare two ints, two doubles, etc. For Object arrays, however, it's not a simple matter of comparing two reference values as ints or longs. We're not comparing the references. We have to compare the objects, according to the class's compareTo() method (if it implements Comparable) or a provided Comparator. The size of an int is known, fixed, and small. The size of an object is unknown, variable, and essentially unbounded. I don't know for sure that that difference is what drove the different approaches, but it is a significant difference, and mergesort is better suited to use cases where we can't fit the entire array into memory at one time. It seems reasonable that we'd get better locality of reference (fewer cache misses, less need to page) with an array of ints than with an array of objects.
Edited by: jverd on Mar 18, 2011 3:16 AM

Sort within an array?

public class Input3
     private String[] input = new String[40];
     private static int StringNum = -1;
     public static final int NUMBER_OF_TEAMS = 3;
     public static final int NUMBER_OF_PLAYERS = 5;
     public Input3()
          //The first six inputs will be for the first team
          input[0] = "LAKERS";
          input[1] = "Kobe Bryant";
          input[2] = "Derek Fisher";
          input[3] = "Shaquille O'Neal";
          input[4] = "Karl Malone";
          input[5] = "Brian Cook";
          //The next six inputs will be for the second team
          input[6] = "MAVERICKS";
          input[7] = "Antoine Walker";
          input[8] = "Dirk Nowitzki";
          input[9] = "Tony Delk";
          input[10] = "Shawn Bradley";
          input[11] = "Travis Best";
          //The next six inputs will be for the third team
          input[12] = "KNICKS";
          input[13] = "Mike Sweetney";
          input[14] = "Allan Houston";
          input[15] = "Howard Eisley";
          input[16] = "Kurt Thomas";
          input[17] = "Shanon Anderson";
     //This method returns the strings one after the other.
     public String getNextString()
          StringNum++;
          return input[StringNum];
}What I'm supposed to do with this is sort that data by last names within each team. By that I mean I have to sort input[1] through input[5] by last names, input[7] through input[11] by last names, and same for the Knicks team. I'm not sure how to do 3 separate sorts within an array.
The output should look like this:
KNICKS:
Sharon Anderson
Howard Eisley
Allan Houston
Mike Sweetney
Kurt Thomas
Any help is greatly appreciated!

Yeah, I don't really understand it. But my professor actually gave us that code to work with to be part of a bigger assignment. I actually just posted another question about the same assignment if you want to look at that to see if it might help.
I dunno how to use the insert link button on here so I'll just let you copy and paste if you are interested in helping me out... Thanks!
It's here >>> http://forum.java.sun.com/thread.jspa?threadID=5268839

Sorting between multiple arrays.

I thought that I had posted this yesterday; however as I can not find my post...
I need assistance with part of a project where I need to sort between multiple arrays; using one of the columns as the sort criteria. The arrays contain integers, strings, and doubles; however I would like to sort and display the arrays alphabetically using the string column. I was told that a bubble array may work, however as I can not find specific information on the use of a bubble array, I really don't know where to start. The arrays look like the following:
productArray[0] = new Product(1, "binder ", 15, 1.5, 0, 0);
productArray[1] = new Product(2, "marker ", 13, .5, 0, 0);
productArray[2] = new Product(3, "paper ", 24, .95, 0, 0);
productArray[3] = new Product(4, "pen ", 5, .25, 0, 0); \
Any assistance that anyone could provide would be greatly appreciated. I am a newbie when it comes to Java and the course materials are extremely vague.
Dman

Thank you for your assistance.
The site that I found to be most helpful was the http://www.onjava.com/lpt/a/3286 site; however I am still experiencing problems. I have added code to the program as noted below:
public class Inventoryprogrampart3
/** Creates a new instance of Main */
* @param args the command line arguments
public static void main(String[] args)
// create Scanner to obtain input from command window
java.util.Scanner input = new java.util.Scanner( System.in );
double totalInventoryValue = 0;
NumberFormat nf = NumberFormat.getCurrencyInstance();
System.out.println(); // Displays a blank line
System.out.println( " Welcome to the Inventory Program - Part 2 " ); // Display the string
System.out.println( " ----------------------------------------- " ); // displays a line of characters
System.out.println(); // Displays a blank line
System.out.println( "This program will output an office supply inventory" ); // Display the string
System.out.println( "listing that includes item numbers for the" ); // Display the string.
System.out.println( "inventoried products, the items product names, the" ); // Display the string.
System.out.println( "quantity of each product in stock, the unit price" ); // Display the string
System.out.println( "for each product, the total value of each products" ); // Display the string
System.out.println( "inventory, and a total value of the entire inventory." ); // Display the string
System.out.println(); // Displays a blank line
System.out.println( "*****************************************************" ); // Displays a line of characters
System.out.println(); // Displays a blank line
Product[] productArray = new Product[ 7 ]; // creates 7 product arrays
// adds data to the 7 arrays
productArray[0] = new Product();
productArray[0].setitemNumber(1);
productArray[0].setproductName ( "binder" );
productArray[0].setitemQuantity(15);
productArray[0].setitemPrice(1.5);
productArray[0].setinventoryValue(0);
productArray[1] = new Product();
productArray[1].setitemNumber(2);
productArray[1].setproductName( "paper" );
productArray[1].setitemQuantity(24);
productArray[1].setitemPrice(.95);
productArray[1].setinventoryValue(0);
productArray[2] = new Product();
productArray[2].setitemNumber(4);
productArray[2].setproductName( "pen" );
productArray[2].setitemQuantity(5);
productArray[2].setitemPrice(.25);
productArray[2].setinventoryValue(0);
productArray[3] = new Product();
productArray[3].setitemNumber(3);
productArray[3].setproductName( "marker" );
productArray[3].setitemQuantity(13);
productArray[3].setitemPrice(.5);
productArray[3].setinventoryValue(0);
productArray[4] = new Product();
productArray[4].setitemNumber(5);
productArray[4].setproductName( "pencil" );
productArray[4].setitemQuantity(28);
productArray[4].setitemPrice(.4);
productArray[4].setinventoryValue(0);
productArray[5] = new Product();
productArray[5].setitemNumber(7);
productArray[5].setproductName( "tape" );
productArray[5].setitemQuantity(14);
productArray[5].setitemPrice(1.65);
productArray[5].setinventoryValue(0);
productArray[6] = new Product();
productArray[6].setitemNumber(6);
productArray[6].setproductName( "staples" );
productArray[6].setitemQuantity(13);
productArray[6].setitemPrice(1.25);
productArray[6].setinventoryValue(0);
System.out.println( "Inventory listing prior to sorting by product name:" );
System.out.println(); // Displays a blank line
System.out.println( "Item #"+"\t"+"Product Name"+"\t"+"Stock"+"\t"+"Price"+"\t"+"Total Value"); // Displays a header line for the inventory array display
System.out.println(); // Displays a blank line
System.out.println( "-----------------------------------------------------" ); // Displays a line of characters
System.out.println(); // Displays a blank line
for (int i=0; i<=6; i++)
Product products = productArray;
String productName = products.getproductName();
int itemNumber = products.getitemNumber();
int itemQuantity = products.getitemQuantity();
double itemPrice = products.getitemPrice();
double inventoryValue = products.getinventoryValue();
System.out.println( productArray[i].getitemNumber() +"\t"+ productArray[i].getproductName() +"\t"+"\t" + productArray[i].getitemQuantity() +"\t"+ nf.format(productArray[i].getitemPrice()) +"\t"+ nf.format(productArray[i].getinventoryValue()) );
Arrays.sort(productArray);
System.out.println( "-----------------------------------------------------" ); // Displays a line of characters
System.out.println(); // Displays a blank line
System.out.println( "Inventory listing after being sorted by product name:" );
System.out.println(); // Displays a blank line
System.out.println( "Item #"+"\t"+"Product Name"+"\t"+"Stock"+"\t"+"Price"+"\t"+"Total Value"); // Displays a header line for the inventory array display
System.out.println(); // Displays a blank line
System.out.println( "-----------------------------------------------------" ); // Displays a line of characters
for(int i=0; i <= 6; i++)
totalInventoryValue = totalInventoryValue + productArray[i].getinventoryValue(); // calculates the total value of the entire products inventory
System.out.println( productArray[i].getitemNumber() +"\t"+ productArray[i].getproductName() +"\t"+"\t"+ productArray[i].getitemQuantity() +"\t"+ nf.format(productArray[i].getitemPrice()) +"\t"+ nf.format(productArray[i].getinventoryValue()) );
}// end for
System.out.println(); // Displays a blank line
System.out.println( "The total value of the entire inventory is: " + nf.format(totalInventoryValue) ); // Displays the entire inventory value
System.out.println(); // Displays a blank line
System.out.println( "*****************************************************" ); // Displays a line of characters
} // end public static void main
}// end public class Inventoryprogrampart3 main
The following utilities have been set:
import java.io.*;
import java.text.*;
import java.util.Scanner;
import java.util.*;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.Comparator;
The program compiles, however when I try to run the program I receive the following error (which outputs about 1/2 way through the program:
Exception in thread "main" java.lang.ClassCastException: Product can not be cast to java language comparable.
(along with a listing of other errors - I can't even get my cut and paste to work on my command prompt window).
I've tried about 50 different iterations and nothing seems to work.

Identical random sort for 2 arrays

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