Append apostrophe with string or string items

This code would help in appending apostrophe with the string on both ends.
If there are comma separated items in string, each one would be appended with apostrophes.
Use: Appending apostrophe for query IN clause

public static final String appendAppsotophe(String str) {

            if(str!=null) {

                  String returnData = "";

                  String array[] = str.split(",");

                  returnData = "'" + array[0] + "'";

                  for (int i = 1; i < array.length; i++) {

                        returnData += ",'" + array[i].trim() + "'";

                  }

                  return returnData;

            } else {

                  return null;

            }

      }