我的类编译的时候怎么找不到文件啊，一个文件夹下其他文件又可以，javac编译 ...

class SavingsAcount
{   
    private double balance;// 存储余额
//    private double interest;
    private double rate;

    public  SavingsAcount( double initia, double rate ){  //构造一个有初始余额账户
        this.balance = initia;
        this.rate = rate;   
    }
    //在账户存款
    public void deposit( double amount ){
        this.balance = this.balance + amount;
    }
    //在账户取款
    public void withdraw( double amount ){
        this.balance = this.balance - amount;
    }
    public double getBalance(){
        return this.balance;
    }
    public double addInterest( ){
        double interest = this.balance * this.rate ;
        return interest;
    }
   
}//请哪位帮我看看，顺便帮我编译下
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java里面的名字不能太长，太长了编译时候发现不了，
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