how to sort an array in java code example

Example 1: sort array java

import java. util. Arrays;
Arrays. sort(array);

Example 2: how to declare an array in java

An array is an ordered collection of elements of the same type, identified by a pair of square brackets []. 
 
 To use an array, you need to:
1. Declare the array with a name and a type. Use a plural name for array, e.g., marks, rows, numbers. All elements of the array belong to the same type.
2. Allocate the array using new operator, or through initialization, e.g.
  
  int[] marks;  // Declare an int array named marks
              // marks contains a special value called null.
int marks[];  // Same as above, but the above syntax recommended
marks = new int[5];   // Allocate 5 elements via the "new" operator
// Declare and allocate a 20-element array in one statement via "new" operator
int[] factors = new int[20];
// Declare, allocate a 6-element array thru initialization
int[] numbers = {11, 22, 33, 44, 55, 66}; // size of array deduced from the number of items

Example 3: Arrays.sort() in java

// java program to sort strings in an alphabetical order
import java.util.Arrays;
public class SortStringAlphabeticalOrder
{
   public static void main(String[] args)
   {
      String[] strAsc = {"Bear","Fox","Deer","Cheetah","Anteater","Elephant"};
      System.out.println("Before sorting: ");
      for(String string : strAsc)
      {
         System.out.println(string);
      }
      // arrays.sort
      Arrays.sort(strAsc);
      System.out.println("-----------------------------------");
      System.out.println("After sorting: ");
      for(String str : strAsc)
      {
         System.out.println(str);
      }
   }
}

Example 4: Arrays.sort() in java

// how to sort an array in java without using sort() method (ascending order)
public class WithoutSortMethod
{
   public static void main(String[] args)
   {
      int temp;
      int[] arrNumbers = {14, 8, 5, 54, 41, 10, 1, 500};
      System.out.println("Before sort: ");
      for(int num : arrNumbers)
      {
         System.out.println(num);
      }
      for(int a = 0; a < arrNumbers.length; a++)
      {
         for(int b = a + 1; b < arrNumbers.length; b++)
         {
            if(arrNumbers[a] > arrNumbers[b])
            {
               temp = arrNumbers[a];
               arrNumbers[a] = arrNumbers[b];
               arrNumbers[b] = temp;
            }
         }
      }
      System.out.println("---------------");
      System.out.println("After sort: ");
      for(int num : arrNumbers)
      {
         System.out.println(num);
      }
   }
}

Example 5: sort array java

Here’s the java program to sort an array using Arrays.sort() method.

import java.util.Arrays;
public class JavaArraySortMethod
{
   public static void main(String[] args)
   {
      String[] strGiven = {"Great Barrier Reef", "Paris", "borabora", "Florence","tokyo", "Cusco"};
      Arrays.sort(strGiven);
      System.out.println("Output(case sensitive) : " + Arrays.toString(strGiven));
   }
}

Example 6: efficient way to sort an array in java

enum Code {
    Str1(1), Str2(2), Str3(3), Str4(4), Str5(5));

    int sortNumber;

    Code(int sortNumber) {
        this.sortNumber = sortNumber;
    }

    int returnNumber() {
        return sortNumber;
    }
};

public static void main(String[] args) {
    List<Object> obj = new ArrayList<Object>();

    Collections.sort(obj, new Comparator<Object>() {
        @Override
        public int compare(Object object1, Object object2) {
            return Code.valueOf(object1.getStr()).returnNumber() > Code.valueOf(object2.getStr()).returnNumber() ? 1 : -1;
        }
    });
}

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Java Example