In this article, you will be learning about string reverse and the different methods to reverse a string in Java.
Java supports numerous methods to reverse a string. You can reverse String using StringBuffer, StringBuilder, iteration, etc. Let’s see the ways to reverse String in Java.
ByteArray method
Sample Java program to ReverseString using ByteArray.
import java.lang.*;
import java.io.*;
import java.util.*;
public class Main {
public static void main(String[] args)
{
String input = "CodersEditor";
byte[] strAsByteArray = input.getBytes();
byte[] result = new byte[strAsByteArray.length];
for (int i = 0; i < strAsByteArray.length; i++)
result[i] = strAsByteArray[strAsByteArray.length - i - 1];
System.out.println(new String(result));
}
}
Output
rotidesredoc
StringBuilder
In stringbuilder method, a string is reversed by using the append method of StringBuilder class.
Sample program to ReverseString using StringBuilder
import java.lang.*;
import java.io.*;
import java.util.*;
public class Main {
public static void main(String[] args)
{
String input = "Coders Editor";
StringBuilder input1 = new StringBuilder();
input1.append(input);
input1.reverse();
System.out.println(input1);
}
}
Output
Rotide sredoc
Reverse a String by converting string to characters one by one
Sample program for Reversing a String by converting string to characters one by one
import java.lang.*;
import java.io.*;
import java.util.*;
public class Main {
public static void main(String[] args)
{
String input = "Coders Editor";
char[] try1 = input.toCharArray();
for (int i = try1.length - 1; i >= 0; i--)
System.out.print(try1[i]);
}
}Output
Rotide sredoc
Swapping Method
In this method, the input string is first Converted into a character array by using the toCharArray() – built-in method of the String Class.
Sample program for reversing a string by swapping method
import java.lang.*;
import java.io.*;
import java.util.*;
public class Main {
public static void main(String[] args)
{
String input = "Coders Editor";
char[] temparray = input.toCharArray();
int left, right = 0;
right = temparray.length - 1;
for (left = 0; left < right; left++, right--) {
char temp = temparray[left];
temparray[left] = temparray[right];
temparray[right] = temp;
}
for (char c : temparray)
System.out.print(c);
System.out.println();
}
}
Output
Rotide sredoc
ListIterator Method
Java also has built in reverse() method for the Collections class. As we know the Collections class reverse() method takes a list object, to reverse the list, we will pass the ArrayList object which is a type of list of characters. For the ArrayList, the input string is converted into ArrayList.
Sample program to Reverse a String using ListIterator
import java.lang.*;
import java.io.*;
import java.util.*;
public class Main {
public static void main(String[] args)
{
String input = "Coders Editor";
char[] hello = input.toCharArray();
List<Character> trial1 = new ArrayList();
for (char c : hello)
trial1.add(c);
Collections.reverse(trial1);
ListIterator li = trial1.listIterator();
while (li.hasNext())
System.out.print(li.next());
}
}
Output
Rotide sredoc
String Buffer method
Sample program using stringbuffer to reverse a string
import java.lang.*;
import java.io.*;
import java.util.*;
public class Test {
public static void main(String[] args)
{
String str = "Coders Editor";
StringBuffer sbr = new StringBuffer(str);
sbr.reverse();
System.out.println(sbr);
}
}
Output
Rotide sredoc
