单例模式
//CopyRight CAnca Software Office. 2006
//Created by CAnca.
import java.util.*;
public class singletonMode{
public static void main(String[] args){
singleton s1 = singleton.init();
System.out.println(s1.getElement(0));
System.out.println(s1.getElement(1));
s1.setElement(0,"日本人");
singleton s2 = singleton.init();
System.out.println(s2.getElement(0));
System.out.println(s2.getElement(1));
}
}
class singleton{
private ArrayList al;
private static singleton single;
protected singleton(){
al = new ArrayList();
al.add("中国人");
al.add("美国人");
}
public static singleton init(){
if(single == null){
single = new singleton();
}
return single;
}
public String getElement(int id){
if(id >= al.size()) - 1;
return ((String)al.get(id));
}
public void setElement(int id,String value){
if(id >= al.size()) - 1;
this.al.set(id,value);
}
}