code: String unescapeString(String st) {
  
          StringBuilder sb = new StringBuilder(st.length());
  
          for (int i = 0; i < st.length(); i++) {
              char ch = st.charAt(i);
              if (ch == '\\') {
                  char nextChar = (i == st.length() - 1) ? '\\' : st.charAt(i + 1);
                  switch (nextChar) {
                  case '\\':
                      ch = '\\';
                      break;
                  case 'b':
                      ch = '\b';
                      break;
                  case 'f':
                      ch = '\f';
                      break;
                  case 'n':
                      ch = '\n';
                      break;
                  case 'r':
                      ch = '\r';
                      break;
                  case 't':
                      ch = '\t';
                      break;
                  /*case '\"':
                      ch = '\"';
                      break;
                  case '\'':
                      ch = '\'';
                      break;*/
                  // Hex Unicode: u????
                  case 'u':
                      if (i >= st.length() - 5) {
                          ch = 'u';
                          break;
                      }
                      int code = Integer.parseInt(
                              "" + st.charAt(i + 2) + st.charAt(i + 3) + st.charAt(i + 4) + st.charAt(i + 5), 16);
                      sb.append(Character.toChars(code));
                      i += 5;
                      continue;
                  }
                  i++;
              }
              sb.append(ch);
          }
          return sb.toString();
      }
docs: Removed octal support