Question

How would i rotate a string array in java for a tetris game i am making. For example, the string array

[
"JJJJ",
"KKKK",
"UUUU"
]

would become

[
"UKJ",
"UKJ",
"UKJ",
"UKJ"
]

I can do it with a char matrix using this code

public char[][] rotate(char[][] toRotate)
{
    char[][] returnChar = new char[toRotate[0].length][toRotate.length];
    for(int rows = 0; rows<toRotate.length; rows++)
    {
        for(int cols = 0; cols<toRotate[0].length; cols++)
        {
            returnChar[cols][toRotate.length-1-rows]=toRotate[rows][cols];
        }
    }
    return returnChar;
}

Answer 1

With the Array String is similar to want you have done:

public static String[] rotate(String [] toRotate)
  {

      String [] returnChar = new String[toRotate[0].length()];
      String [] result = new String[toRotate[0].length()];
      Arrays.fill(returnChar, "");

      for(int rows = 0; rows<toRotate.length; rows++)
          for(int cols = 0 ; cols < toRotate[rows].length(); cols++)
              returnChar[cols] = returnChar[cols] + toRotate[rows].charAt(cols);

      for(int i = 0; i < returnChar.length; i++)
          result[i] =  new StringBuffer(returnChar[i]).reverse().toString();

      return result;
  }

I go through all char in each String on array toRotate, concat this char (toRotate[rows].charAt(cols)) to each String returnChar[cols] on the array returnChar