reversing method string 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

As we know that String is immutable. String class do not have reverse() method.