小弟谢了一个计算器程序，一样的代码就是改了下输入的数，然后就一直报错求解答

这个是我第一次敲的读取输入的方法运行，可以正常

static HashMap ops=new HashMap();
static{
try {

            File f1=new File("E:\\app.txt");
            FileWriter fw = new FileWriter(f1);
            BufferedWriter bw=new BufferedWriter(fw);
            bw.write("+:com.cisst.Add");
            bw.newLine();
            bw.write("-:com.cisst.Jian'");
            bw.newLine();
            bw.close();
            fw.close();
            FileReader fr=new  FileReader(f1);
            BufferedReader br=new BufferedReader(fr);
            String line=null;
            String[] sps=null;
            while((line=br.readLine())!=null){
                sps=line.split(":");
                ops.put(sps[0],sps[1]);
            }
            br.close();
            fr.close();

        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } 
}
public static Calculator createJiSuan(String op) throws InstantiationException, IllegalAccessException, ClassNotFoundException{
    Calculator ca = null;
    ca = (Calculator)Class.forName(ops.get(op)).newInstance();

    return ca;

    这是我第二敲的，两个基本一样，这个就是运行报错

    static HashMap<String,String> ops=new HashMap<String,String>();
static{
    try {


        File f1=new File("E:\\yunsuan.txt");
        FileWriter fw=new FileWriter(f1);
        BufferedWriter bw=new BufferedWriter(fw);
        bw.write("+:com.lianxi.Add");
        bw.newLine();
        bw.write("-:com.lianxi.Jian'");
        bw.newLine();
        bw.close();
        fw.close();
        FileReader fr=new  FileReader(f1);
        BufferedReader br=new BufferedReader(fr);
        String line=null;
        String[] sps=null;
        while((line=br.readLine())!=null){
            sps=line.split(":");
            ops.put(sps[0],sps[1]);
        }
        br.close();
        fr.close();
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}
public static Calculator createJiSuan(String op) throws InstantiationException, IllegalAccessException, ClassNotFoundException{
    Calculator ca = null;
    ca = (Calculator)Class.forName(ops.get(op)).newInstance();

    return ca;



    求指教

是不是你的txt文件格式有问题？