FileIO

1.    字节流  

public static void main(String[] args) throws IOException { // TODO Auto-generated method stub File file=new File("E:/S2226.txt"); //创建文件 file.createNewFile(); if(file.exists()){ System.out.println("存在"); //判断是否存在 } long lastModified = file.lastModified();//文件最后一次修改时间 对比时间1970年 1月1日 输出数字为毫秒 System.out.println(lastModified); System.out.println(file.length()); } public static void main(String[] args) throws IOException { // TODO Auto-generated method stub FileInputStream fis=new FileInputStream("E:/S2226.txt"); byte[] bytes=new byte[1024]; int data=fis.read(bytes); while(data!=-1){ String temp=new String(bytes,0,data); System.out.println(temp); data=fis.read(bytes); }

    记得关闭流     

输出的效果图 如下：

这里要关闭流.

2.  字符流  

public static void main(String[] args)throws IOException { // TODO Auto-generated method stub //读取文件 Reader reader=new FileReader("E:/S2226.txt"); BufferedReader bf=new BufferedReader(reader); String line; while ((line=bf.readLine())!=null){ System.out.println(line); } bf.close(); reader.close(); } public static void main(String[] args)throws IOException { // TODO Auto-generated method stub Writer writer=new FileWriter("E:/S2226.txt"); BufferedWriter bw=new BufferedWriter(writer); String words="嗯哼？"; bw.write(words); bw.close(); writer.close(); }

public static void main(String[] args) throws IOException{ // TODO Auto-generated method stub InputStream is=new FileInputStream("D:/001.gif"); DataInputStream dis=new DataInputStream(is); OutputStream os=new FileOutputStream("E:/002.gif"); DataOutputStream dos=new DataOutputStream(os); byte[] bytes=new byte[1024]; int data; while((data=dis.read(bytes))!=-1){ dos.write(bytes,0,data); } dos.close(); os.close(); dis.close(); is.close(); System.out.println("粘贴成功"); }