我真的需要这个java类的帮助:
我的班级如下:
public class Date {
// fields
private int month;
private int day;
private int year;
// constructor
public Date(int month, int day, int year){
this.month = month;
this.day = day;
this.year = year;
}
public void setMonth(int month){
this.month = month;
}
public void setDay(int day){
this.day = day;
}
public void setYear(int year){
this.year = year;
}
public int getMonth(){
return month;
}
public int getDay(){
return day;
}
public int getYear(){
return year;
}
public String displayDate(){
return month + "/" + day + "/" + "/" + year;
}
public int add( int n)
{
if (n <= 20)
{
if (month==1 || month==3 || month==5 || month==7 || month==8 || month==10 || month==12)
{
if ((day+n > 0) && (day+n <=31))
day= day+n;
else
month +=1;
if(month>12)
year+=1;
}
if (month==4 || month==6 || month==9 || month==11)
{
if ((day+n >0) && (day+n <=30))
day= day+n;
else
month+= 1;
if (month>12)
year+=1;
}
}
}
}
当我运行它时,我在 add 方法上收到错误缺少返回语句?此方法应该在日、月和年中添加一些天 (n)。任何想法我将如何解决这个问题?