1. import java.io.File;
2. File f1 = new File(“d:\a.txt”);
3. public File(String pathname) public File(String parent, String child)
4. public boolean createNewFile() throws IOException创建文件
5. public boolean delete()删除文件或文件夹，如果文件夹，则需要空
6. public boolean exists()是否存在
7. public String getAbsolutePath()
8. public String getName()
9. public String getParent()
10. public boolean isDirectory()
11. public boolean isFile()
12. public long length()
13. public String[] list()所有文件夹和文件，非绝对路径
14. public File[] listFiles()当前文件夹下所有的文件对象
15. public boolean mkdir()
16. public boolean mkdirs()如果父目录不存在，则创建
17. public boolean renameTo(File dest)如果有同名的，修改失败
18. public boolean setReadOnly()改属性
19. try{ boolean b = f3.createNewFile(); }catch(Exception e){e.printStackTrace();}
20. String[] s = f1.list(); for(int i = 0;i < s.length;i++){ System.out.println(s[i]); }
21. 文件的输入和输出java.io.PrintWriter
22. PrintWriter(file:FILE) PrintWriter(filename:String)
23. print(string,int,long...) println
24. 最后要close();
25. java.util.Scanner
26. Scanner(file:File, name:String);
27. Close();
28. hasNext():boolean;如果还有可读数据则为true
29. Next():string nextLine():string nextByte()...
30. InputStream {FileInputStream FilterInputStream{DataInputStream, BufferInputStream} ObjectInputStream}
OutputStream{FileOutputSteam FilterOutputStream{DataOutputStream BufferInputStream} ObjectOutputStream}
31. InputStream{read(); available();close();skip();markSupported();mark();reset()
32. OutputStream{write(); close(); flush()}
33. DataInputStream{readBoolean(); readByte(); readChar()...readUTF();readLine()}
34. DataOutputStream{writeBoolean()...}
35. java.io.RandomAccessFile{close();getFilePointer();lenght();read();seek();setLength();skipBytes();write();