【求助】自定义类方法的问题

rt，以下是代码

public class Branch{

String subName;
int salary;
int totalBooks;
int totalHrs;

Branch(String subName1,int totalBooks1 ){
subName=subName1;
totalBooks=totalBooks1;
}

void calculata(){
int totalHrs=totalBooks*2;
System.out.println(subName+"学科的总时数是"+totalHrs);
}


public static void main(String[] args){
Branch Science1=new Branch("科学",10);
Branch Arts1=new Branch("艺术",14);
Science1.calculata();
Arts1.calculata();
System.out.println("----------------------");
Science s1;
s1.printall(Science1);
Arts a1;
a1.printall(Arts1);
}

class Science{
void printall(Branch Science1){
Science1.calculata();
}
}
class Arts{
void printall(Branch Arts1){
Arts1.calculata();
}
}
}

烦请大侠们帮忙看看

[此贴子已经被作者于2007-7-26 20:21:52编辑过]

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问题是什么？
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应该这里有问题把
Science s1;
s1.printall(Science1);
Arts a1;
a1.printall(Arts1);

----------------解决方案--------------------------------------------------------
class Science{
void printall(Branch Science1){
Science1.calculata();
}
}
class Arts{
void printall(Branch Arts1){
Arts1.calculata();
}
}
这两个类应该在Branch类的外面.还有:
Science s1;
Arts a1;
是不是还没有初始化!

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多谢热心的各位
问题以解决了
Science和Arts声明成static就通过编译了
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