if (date != null ? !date.equals(solution1.date) : solution1.date == null) return true;
if (solution != null ? !solution.equals(solution1.solution) : solution1.solution == null) return true;
if (string != null ? !string.equals(solution1.string) : solution1.string == null) return true;
Date date = new Date();
System.out.println(new Solution(0, "", 0d, date, null)
.equals(new Solution(0, "ыф", 0d, date, null)));