JAVA基础补漏--文件读取

public class Test2 {


    public static void main(String[] args) throws IOException {

        FileInputStream fis = new FileInputStream("1.txt");
        int len = 0;
        byte[] bytes = new byte[200];
        while ((len = fis.read(bytes)) != -1)
        {
            System.out.println(len);
            System.out.println(new String(bytes,0,len));
        }


    }



}

文件复制

public class Test2 {


    public static void main(String[] args) throws IOException {

        FileInputStream fis = new FileInputStream("C:\sdcs\1.png");

        FileOutputStream fos = new FileOutputStream("D:\sdcs\1.png");

        int len = 0;
        byte[] bytes = new byte[1024];
        while ((len = fis.read(bytes)) != -1)
        {
            
            fos.write(bytes,0,len);
        }

        fos.close();
        fis.close();




    }



}