java之IO流

 1 public class Demo1_FileInputStream {
 2 
 3     public static void main(String[] args) throws IOException {
 4         //demo1();
 5         FileInputStream fis = new FileInputStream("a.txt");  // 内容为  abc
 6         int x;
 7         while((x = fis.read())!=-1) {
 8             System.out.println(x);
 9         }
10     }
11 
12     public static void demo1() throws FileNotFoundException, IOException {
13         FileInputStream fis = new FileInputStream("a.txt");  // 内容为  abc
14         int x = fis.read();                                  // x = 97
15         System.out.println(x);                               // 当 文件中的内容读完后再读时  返回值为 -1
16         fis.close();
17     }
18 
19 }