3-26java的日子--IO流，各种流

字节流的IO：

import java.io.BufferedOutputStream;

import java.io.DataOutputStream;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

public class BufferedInputStreams {

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

File f1 = new File("D://io//file.txt");

if (!f1.exists()) {

f1.createNewFile();

}

byte[] b=new byte[5];

System.out.println(f1.getAbsolutePath());

DataOutputStream out=new DataOutputStream(new BufferedOutputStream(new FileOutputStream(f1)));

out.write(10);

out.write('s');

out.write('b');

f1.length();//长度为什么是000000000000？？？？？？？？？？

// System.out.println(f1.length());

out.flush();

out.close();

}

}

字符流的IO:

import java.io.BufferedOutputStream;

import java.io.BufferedReader;

import java.io.DataOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStreamReader;

public class ReadandWrite {

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

File f1 = new File("D://io//file.txt");

if (!f1.exists()) {

f1.createNewFile();

}

byte[] b=new byte[5];

System.out.println(f1.getAbsolutePath());

BufferedReader in=new BufferedReader(new InputStreamReader(new FileInputStream(f1)));

in.read();

f1.length();//长度为什么是000000000000？？？？？？？？？？

System.out.println(Integer.toString((in.read())));

in.close();

}

}