Sort a String Alphabetically in Java

Sorting a string alphabetically means rearranging its characters in order, from A to Z. For example, the string "java" becomes "aajv" after sorting.

Different ways to sort a String Alphabetically

There are two ways to do this in Java using different approaches -

• Using toCharArray() and Arrays.sort() Method

• Sorting the array manually

Using toCharArray() and Arrays.sort() Method

The toCharArray() method of this class converts the String to a character array and returns it. To sort a string value alphabetically -

• Get the required string.

• Convert the given string to a character array using the toCharArray() method.

• Sort the obtained array using the sort() method of the Arrays class.

• Convert the sorted array to a String by passing it to the constructor of the String array.

Example

Following is an example to sort a string alphabetically -

import java.util.Arrays;
import java.util.Scanner;

public class SortingString {
   public static void main(String args[]) {
      String str = "Hello welcome to Tutorialspoint";
      char charArray[] = str.toCharArray();
      Arrays.sort(charArray);
      System.out.println(new String(charArray));
   }
}

Let us compile and run the above program, which will give the following result -

Hello welcome to Tutorialspoint

Sorting the array manually

The following are the steps to sort the array manually -

• Get the required string.

• Convert the given string to a character array using the toCharArray() method.

• Compare the first two elements of the array.

• If the first element is greater than the second, swap them.

• Then, compare the 2^nd and 3^rd elements if the second element is greater than the 3^rd, swap them.

• Repeat this till the end of the array.

Example

Following is an example -

import java.util.Arrays;
import java.util.Scanner;

public class SortingString {
   public static void main(String args[]) {
      int temp, size;
      String str = "Tutorialspoint";
      char charArray[] = str.toCharArray();
      size = charArray.length;
      for(int i = 0; i < size; i++ ) {
         for(int j = i+1; j < size; j++) {
            if(charArray[i]>charArray[j]) {
               temp = charArray[i];
               charArray[i] = charArray[j];
               charArray[j] = (char) temp;
            }
         }
      }
      System.out.println("Third largest element is: "+Arrays.toString(charArray));
   }
}

Let us compile and run the above program, which will give the following result -

Tutorialspoint
Third largest element is: [T, a, i, i, l, n, o, o, p, r, s, t, t, u]