reversing string in java code example

Example 1: java reverse a string

// Library approach
public static String solution(String str) {
	// StringBuilder is not thread-safe, use StringBuffer
	return new StringBuffer(str).reverse().toString();
}

// DIY approach
public static String solution(String str) {
	char[] chars = str.toCharArray();
	for(int i = 0, j = str.length() - 1; i < j; i++, j--) {
		char ch = chars[i];
		chars[i] = chars[j];
		chars[j] = ch;
	}
	return new String(chars);
}

Example 2: reverse a string in java

Solution 1 

public static String StrReverse(String str) {

String reverse="";

for(int i=str.length()-1; i >= 0; i--)

reverse += str.toCharArray()[i];

 

return  reverse;

}

 

Solution 2 (using string buffer)

public  static String  Reverse(String str) {

return new StringBuffer(str).reverse().toString());

}

Example 3: how to reverse a string in java

public class ReverseString {
    public static void main(String[] args) {
        String s1 = "neelendra";
        for(int i=s1.length()-1;i>=0;i--)
            {
                System.out.print(s1.charAt(i));
            }
    }
}

Example 4: string reverse in java

String str = "Hello";
String reverse(String str){
  StringBuilder sb = new StringBuilder();
  sb.append(str);
  sb.reverse();
  return sb.toString();
}

Example 5: Reverse a string in java

// reverse a string using toCharArray() method
class ReverseUsingToCharArrayMethod
{
   public static void main(String[] args)
   {
      String str = "Hello World Java";
      char[] chTemp = str.toCharArray();
      int left, right = 0;
      right = chTemp.length - 1;
      for(left = 0; left < right ; left++, right--)
      {
         // swap values
         char temp = chTemp[left];
         chTemp[left] = chTemp[right];
         chTemp[right]=temp;
      }
      for(char c : chTemp)
         System.out.print(c);
      System.out.println();
   }
}

Example 6: reverse a string in java

// Not the best way i know but i wanted to challenge myself to do it this way so :)
public static String reverse(String str) {
  char[] oldCharArray = str.toCharArray();
  char[] newCharArray= new char[oldCharArray.length];
  int currentChar = oldCharArray.length-1;
  for (char c : oldCharArray) {
    newCharArray[currentChar] = c;
    currentChar--;
  }
  return new String(newCharArray);
}