IO字节流和缓冲流
IO字节流的读取和写入
读取
1 import java.io.FileInputStream;
2 import java.io.FileNotFoundException;
3 import java.io.IOException;
4
5 public class Test {
6 public static void main(String[] args) {
7 try (FileInputStream fis = new FileInputStream("java.txt")
8 ) {
9 byte[] bytes = new byte[40];
10 int temp;
11 while ((temp = fis.read(bytes)) != -1) {
12 System.out.println(new String(bytes, 0, temp));
13 }
14 } catch (FileNotFoundException e) {
15 e.printStackTrace();
16 } catch (IOException e) {
17 e.printStackTrace();
18 }
19 }
20 }
写入
1 import java.io.*;
2
3 public class Test {
4 public static void main(String[] args) {
5 try (FileOutputStream fos = new FileOutputStream("file" + File.separator + "1024.txt", true) //写入时不清除原有数据
6 ) {
7 fos.write("Hello".getBytes());
8 fos.write("\n".getBytes()); //换行
9 fos.write("Wrold!".getBytes());
10 fos.flush(); //刷新
11 } catch (FileNotFoundException e) {
12 e.printStackTrace();
13 } catch (IOException e) {
14 e.printStackTrace();
15 }
16 }
17 }
IO字节流的文件拷贝
1 import java.io.*;
2
3 public class Test {
4 public static void main(String[] args) {
5 try (
6 FileOutputStream fos = new FileOutputStream("file" + File.separator + "new.txt");
7 FileInputStream fis = new FileInputStream("java.txt")
8 ) {
9 int temp;
10 byte[] bytes = new byte[50];
11 while ((temp = fis.read(bytes)) != -1) {
12 fos.write(bytes);
13 }
14 } catch (FileNotFoundException e) {
15 e.printStackTrace();
16 } catch (IOException e) {
17 e.printStackTrace();
18 }
19 }
20 }
IO缓冲流的读取和写入
读取