luis_liu
发贴: 5
积分: 0
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于 2004-12-28 20:10
class BirthDate { private int day; private int month; private int year; public BirthDate(int d,int m,int y){ day = d; month = m; year = y; } public void setDay(int d){ day = d; } public void setMonth(int m){ month = m; } public void setYear(int y){ year = y; } public int getDay(){ return day; } public int getMonth(){ return month; } public int getYear(){ return year; } public void display(){ System.out.println(day + " - " + month + " - " + year); } }
public class Example{ public static void main(String args[]){ Example ex = new Example(); int date = 9; BirthDate d1= new BirthDate(7,7,1970); BirthDate d2= new BirthDate(1,1,2000); ex.change1(date); ex.change2(d1); ex.change3(d2); System.out.println("date=" + date); d1.display(); d2.display(); } public void change1(int i){ i = 1234; } public void change2(BirthDate b){ b = new BirthDate(22,2,2004); ////////////////// } public void change3(BirthDate b){ b.setDay(22); }
}
/////////// /* 得到结果 date =9 7-7-1970 22-1-2000
复合类是可以引用的
b = new BirthDate(22,2,2004); 为什么没能改变其值
请赐教 */
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