import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date; 
import java.util.GregorianCalendar;
import java.util.Scanner;

public class TestASE {
    public static void main(String[] args) throws ParseException {
        System.out.println(
 
"請輸入年齡：");
        Scanner scanner = new Scanner(System.in);
        String age = scanner.nextLine();
        System.out.println("請輸入分數：");
        String score = scanner.nextLine();
        System.out.println("請輸入入學日期（格式為2020-10-20）：");
        String date = scanner.nextLine();
        
        
 
//轉換為整數、浮點型、日期類型
        int age2 = Integer.parseInt(age);
        double score2 = Double.parseDouble(score);
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
        Date date2 = df.parse(date);//先轉為時間類型
        Calendar c = new GregorianCalendar();
        c.setTime(date2);
        
        System.out.println(
 
"年齡" + age2 + "歲\n"
                + "分數：" + score2 + "分\n"
                + "入學時間" + date2);
    }
}

轉自https://blog.csdn.net/xxyh1234/article/details/89495876

Java - 尚學堂第八章常用類（將輸入的string類型的值轉為整數、浮點型、日期類型）