打印原始数组未排序的数组

Question

I am looking to print out my original unsorted array, I have it printing in order and sorted but I can't seem to get the original one to print out unsorted. I have used printRuleAndArray(String rule) and I have also used LengthCompare for the new sorted array, my problem is the original!!!

import java.util.*;
import java.util.Arrays;

// Example of how to sort an array
public class Sorting2
{
    //declare an array of strings
    static String[] nameArray = {"Alan", "Peter", "Ed", "Stephen", "Pheadraa"};

    public static void main(String[] args)
    {

        // sorting by length
        Arrays.sort(nameArray, new LengthCompare());
        //print out elements of array
        System.out.println(Arrays.toString(nameArray));
        //count the number of elements in the array
        int counter=nameArray.length;
        //print out numeric number of elements in array
        System.out.println("Number of elements in array: " + counter);
        //print out sorted array with shortest first and longest last
        printRuleAndArray("Sorted list by name length:");

    }

Answer 1

Arrays.sort() will always sort the array you pass into it, it doesn't produce a fresh copy - so if you really need the unsorted array to hang around as well as the sorted array, then you'll have to make a copy of it:

String copyArr[] = new String[nameArray.length];
System.arraycopy( nameArray, 0, copyArr, 0, nameArray.length );

However, preferable to this approach (if feasible) would just be to do all the operations you need on the unsorted array (such as printing it or converting it to a string), then sort it afterwards.

As pointed out in the comment, Arrays.copyOf() could also be used to accomplish the same thing.

Answer 2

Arrays.sort will have altered your original array. Your choices are to either print your original array before sorting it, or to copy your original array and sort the copy.

Answer 3

Call String unsortedArr = Arrays.toString(nameArray); before array sorting, and when you need to print unsorted array just call System.out.println(unsortedArr);

Answer 4

Arrays.sort() sorts the array you pass into it. If you would like the original array later, copy the array first and then sort that array.

Answer 5

 for(String arr : nameArray ) {  //arr gets successively each value in nameArray.
System.out.println(arr);
}

this example is using foreach loop

Answer 6

Do something like this

    String orig = Arrays.toString(nameArray);
    Arrays.sort(nameArray, new LengthCompare());
    String sorted = Arrays.toString(nameArray);

    System.out.println(orig);
    System.out.println(sorted);