How to reverse a string

Question

I need to reverse the string of a user\'s input.

I need it done in the simplest of ways. I was trying to do reverseOrder(UserInput) but it wasn\'t working.

Answer 1

There is an interesting method to do it so too.

   String input = "abc";
   //Here, input is String to reverse
   int b = input.length();
   String reverse = ""; // Declaring reverse String variable
     while(b!=0){
        //Loop for switching between the characters of the String input
        reverse += (input.charAt(b-1));
        b--;
        }
        System.out.println(reverse);

Answer 2

I prefer using Apache's commons-lang for this kind of thing. There are all kinds of goodies, including:

StringUtils.reverse("Hello World!");

yields: !dlroW olleH

StringUtils.reverseDelimited("Hello World!", ' ');

yields: World! Hello

Answer 3

If you are new to programming, which I guess you are, my suggestion is "Why use simple stuff?". Understand the internals and play some!!

public static void main(String[] args) {
String str = "abcasz";
char[] orgArr = str.toCharArray();
char[] revArr = new char[orgArr.length];
for (int i = 0; i < orgArr.length;i++)  {
revArr[i] = orgArr[orgArr.length - 1 - i];
}
String revStr = new String(revArr);
System.out.println(revStr);

Answer 4

Without going through the char sequence, easiest way:

public String reverse(String post) {       
    String backward = "";
    for(int i = post.length() - 1; i >= 0; i--) {
        backward = backward + post.substring(i, i + 1);
    }        
    return backward;
} 

Answer 5

new StringBuilder(str).reverse().toString()

java.util.Collections.reverseOrder is for sorting in reverse of normal order.

Answer 6

    public String reverseString(final String input_String)
          {
              char temp;
              char[] chars = input_String.toCharArray();
              int N = chars.length;
              for (int i = 0 ; i < (N / 2) ; i++)
              {
                  temp = chars[i];
                  chars[i] = chars[N - 1 - i];
                  chars[N - 1 - i] = temp;
              }

              return new String(chars);
          }

Run :

    Pandora
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