java中的简单For循环

 public void reverseString(char[] s) {
    int length = s.length;
    for (int i = 0; i < s.length / 2; i++) {
        // swaping character
        char temp = s[length - i - 1];
        s[length - i - 1] = s[i];
        s[i] = temp;
    }
}

String string="whatever";
String reverse = new StringBuffer(string).reverse().toString();
System.out.println(reverse);

下面是一个使用递归的例子:

public void reverseString() {
    String alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String reverseAlphabet = reverse(alphabet, alphabet.length()-1);
}

String reverse(String stringToReverse, int index){
    if(index == 0){
        return stringToReverse.charAt(0) + "";
    }

    char letter = stringToReverse.charAt(index);
    return letter + reverse(stringToReverse, index-1);
}

它是非常简单的在最少的代码行

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));
            }
    }
}

public static String revString(String str){
    char[] revCharArr = str.toCharArray();
    for (int i=0; i< str.length()/2; i++){
        char f = revCharArr[i];
        char l = revCharArr[str.length()-i-1];
        revCharArr[i] = l;
        revCharArr[str.length()-i-1] = f;
    }
    String revStr = new String(revCharArr);
    return revStr;
}

public void reverString(){
System.out.println("Enter value");
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
 try{

  String str=br.readLine();
  char[] charArray=str.toCharArray();
  for(int i=charArray.length-1; i>=0; i--){
   System.out.println(charArray[i]);
  }
  }
   catch(IOException ex){
  }