Java中的繼承

Question

我只是在學習如何在Java中使用繼承。 該程序的目的是編寫包含有關某些日志條目信息的類，並提供設置和獲取適當信息的方法。 請讓我知道是否需要任何更正。

ArithmeLog.java

//super class ArithmeLog with three functions to capture three instances

import java.util.*;

import java.text.*;

public class ArithmeLog {

 public ArithmeLog() {

 }



 public void captid1(String a) {

      System.out.println("");

 }



 public void captid2(String SongName) {

      System.out.println("");

 }

 public void Date() {

      Date capttim = new Date( );

      SimpleDateFormat formt = new SimpleDateFormat

 ("E yyyy.MM.dd 'at' hh:mm:ss a zzz");

      System.out.println("Time is : " +

formt.format(capttim));

   }

    }

SongLog.java

//class SongLog which inheriting ArithmeLog class

import java.util.*;

import java.text.*;

public class SongLog extends ArithmeLog {

 public SongLog() {

      super();

      System.out.println("");

 }



 @Override

 public void captid1(String SongID) {

      System.out.println("SongID is: "+SongID);

 }



 @Override

 public void captid2(String SongName) {

      System.out.println("Song name is: "+SongName);

 }

 @Override

 public void Date() {

      Date capttim = new Date( );

      SimpleDateFormat formt = new SimpleDateFormat

  ("E yyyy.MM.dd 'at' hh:mm:ss a zzz");

      System.out.println(" Date and time is : " +

  formt.format(capttim));

 }

 }

 AdLog.java

// AdLog class which inheriting ArithmeLog class

import java.util.*;

import java.text.*;

 public class AdLog extends ArithmeLog {

 public AdLog() {

      super();

      System.out.println("");

 }



 @Override

 public void captid1(String AdvertisementID) {

 System.out.println("AdvertisementID is:"+AdvertisementID);

 }



 @Override

 public void captid2(String AdvertiserID) {

      System.out.println("AdvertiserID is:"+AdvertiserID);

 }

 @Override

 public void Date() {

      Date capttim = new Date( );

      SimpleDateFormat formt = new SimpleDateFormat

 ("E yyyy.MM.dd 'at' hh:mm:ss a zzz");

      System.out.println(" Date and time is : " +

 formt.format(capttim));

 }

 }

  Mainpgm.java

// main class creating objects of classes and calling methods

public class Mainpgm {

 public static void main(String[] args) {

      //creating first object of classes

      ArithmeLog animal = new ArithmeLog();

      AdLog ao1 = new AdLog();

      SongLog so1 = new SongLog();

      System.out.println();

      ao1.captid1("1");

      ao1.captid2("7");

      ao1.Date();

      so1.captid1("1");

      so1.captid2("songg1");

      so1.Date();

      //creating second object of classes

      AdLog ao2 = new AdLog();

      SongLog so2 = new SongLog();

      ao2.captid1("2");

      ao2.captid2("ad2");

      ao2.Date();

      so2.captid1("2");

      so2.captid2("songg2");

      so2.Date();

      //creating third object of classes

      AdLog ao3 = new AdLog();

      SongLog so3 = new SongLog();

      ao3.captid1("3");

      ao3.captid2("ad3");

      ao3.Date();

      so3.captid1("6");

      so3.captid2("songg3");

      so3.Date();



    }

  }

Answer 1

根據您的評論，您是否所有這些都在1個文件中？

每個“節”都應在其自己的文件中。 因此，一個名為ArithmeLog.java的文件ArithmeLog.java的所有內容都與SongLog.java ，然后是一個名為SongLog.java的文件，其下具有所有內容， SongLog.java 。