P376 throws方式

      
public class ExceptionTest2 {
    public static void main(String[] args)throws IOException {
       try {
           method2();
       }catch (IOException e){
           e.printStackTrace();
       }
       method3();
    }
    public static void method3(){
        try {
            method2();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public static void method2()throws FileNotFoundException,IOException{//调用method1出现异常，要往上抛
        method1();
    }
    public static void method1()throws FileNotFoundException, IOException {
         File file = new File("Hello.txt");
           FileInputStream fis = new FileInputStream(file);
         int data=fis.read();
           while (data!=-1){
               System.out.println((char)data);
              data=fis.read();
           }
         fis.close();
    }
}