namespace collertion{ public class Collertion{
private static Collertion collertion; private Collertion(){
}
public static collertion getInstance(){
if(collertion==null){
collertion = new collertion();
}
return collertion;
}
}
}
原文：http://www.cnblogs.com/jssyzlm/p/6485368.html