docs: public static int[] validate4(int[] data, String paramName){
          if(data == null) {
              return null;
          }
  
          Preconditions.checkArgument(data.length == 1 || data.length == 2 || data.length == 4,
                  "Need either 1, 2, or 4 %s values, got %s values: %s",
                  paramName, data.length, data);
  
          if(data.length == 1){
              return new int[]{data[0], data[0], data[0], data[0]};
          } else if(data.length == 2){
              return new int[]{data[0], data[0], data[1], data[1]};
          } else {
              return data;
          }
      }