hashcode方法编写规则

@Override
public int hashCode() {
int result = 17;

long double2long = Double.doubleToLongBits(weight);

result = 37*result + (int)(id ^ id>>>32); //long型 f ^ (f >>> 32)
result = 37*result + (active ? 0 : 1); //boolean型 f?0:1
result = 37*result + (int)(double2long ^ double2long >>> 32); // double 先转换long再按照long型转换
result = 37*result + age; //int,short,byte,char (int)f
result = 37*result + (int)sex;
result = 37*result + (int)ss;
result = 37*result + (int)bb;

return result;
}