public class Application {
public static void main(String[] args) {
StudentRepository myStudent = new StudentRepository();
myStudent.addStudent("St","Rt","0742", "1993.03.04", PersonGender.MALE, "1930303");
myStudent.addStudent("Sr","Ro","0742", "1994.03.04", PersonGender.MALE, "1940304");
myStudent.addStudent("Se","Rb","0742", "1995.03.04", PersonGender.MALE, "1950305");
myStudent.addStudent("Sm","Re","0742", "1996.03.04", PersonGender.MALE, "1950306");
myStudent.deleteStudent("Stumer","Robert","0742", "1992.03.04", PersonGender.MALE, "null");
myStudent.deleteStudent("Sr","Ro","0742", "1994.03.04", PersonGender.MALE, "1940304");
myStudent.displayStudents();
myStudent.calculateAge();// not working
}
}
public static int calculateAge(Date birthDate) {
/** if ((birthDate != null) && (currentDate != null)) {
return Period.between(birthDate, currentDate).getYears();
} else {
return 0;
}*/
int thisYear = Calendar.getInstance().get(Calendar.YEAR);
Calendar birthdateCalendar = Calendar.getInstance();
birthdateCalendar.setTime(birthDate);
int birthYear = birthdateCalendar.get(Calendar.YEAR);
int yearsSinceBirth = thisYear - birthYear;
return yearsSinceBirth;
}
日期代码是构造函数的第四个参数，在它下面是我为年龄计算实现的方法
int age = (new Date().getTime() - birthDate.getTime())/(1000 * 60*60 * 24*365):
好吧，如果您能够/允许使用java.time，那么您就可以在一个语句/仅仅几行中计算出一个人的年龄超过他/她的出生日期。
请参见此示例:
public static int getAgeInFullYears(LocalDate birthDate) {
Period period = Period.between(birthDate, LocalDate.now());
return period.getYears();
}
您必须将出生日期作为java.time.localdate的实例传递，您可以从之前的字符串（格式化为问题代码中的字符串）中解析该实例，请参见以下示例用法:
public static void main(String[] args) {
// provide the date of birth as String
String birthday = "1993.03.04";
// parse it to a LocalDate using a formatter that parses the String format
LocalDate birthDate = LocalDate.parse(birthday, DateTimeFormatter.ofPattern("yyyy.MM.dd"));
// then calculate the years using the method
int ageInYears = getAgeInFullYears(birthDate);
// and print some result statment
System.out.printf("The person is %d years old (date of calculation %s)",
ageInYears,
LocalDate.now());
}
输出如下:
The person is 27 years old (date of calculation 2020-06-11)
您可以使用新的java.time类，它们更方便。
final LocalDate birth = birthDate.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
final LocalDate now = LocalDate.now();
final int age = Period.between(birth, now).getYears();
