IO流—字符流

字节流：视频，图片

字符流：文本文件

• 字符输入流：Reader（父）---》FileReader（低级流）-->BufferedReader（高级流）
• 字符输出流：Writer（父）---》FileWriter（低级流）-->BufferedWriter（高级流）

低级流：也称节点流，节点流类型常见的有：对文件操作的字符流有FileReader/FileWriter，字节流有FileInputStream/FileOutputStream

高级流：也称缓冲流，缓冲流要“套接”在相应的节点流之上，对读写的数据提供了缓冲的功能，提高了读写效率，同时增加了一些新的方法，常用缓冲流有BufferedReader、BufferedWriter。

 字符输入demo：读取txt中的文本

源代码：

 1 import java.io.*;
 2 
 3 public class ZiFu {
 4     public static void main(String[] args) {
 5     ZiFu.ReadFile("D:/temp/temp.txt");
 6     }
 7     public static void ReadFile(String address){
 8         FileReader fileReader=null;
 9         BufferedReader bufferedReader=null;
10         try {
11             fileReader=new FileReader(new File(address));
12             bufferedReader=new BufferedReader(fileReader);
13             int data=0;
14             try {
15                 while ((data=bufferedReader.read())!=-1){
16                     System.out.print((char)data);
17                 }
18             } catch (IOException e) {
19                 e.printStackTrace();
20             }
21         } catch (FileNotFoundException e) {
22             e.printStackTrace();
23         }
24 
25     }
26 }

或者:

 1 import java.io.*;
 2 
 3 public class ZiFu {
 4     public static void main(String[] args) {
 5     ZiFu.ReadFile("D:/temp/temp.txt");
 6     }
 7     public static void ReadFile(String address){
 8         FileReader fileReader=null;
 9         BufferedReader bufferedReader=null;
10         try {
11             fileReader=new FileReader(new File(address));
12             bufferedReader=new BufferedReader(fileReader);
13             int data=0;
14             try {
15                 while ((data=bufferedReader.read())!=-1){
16                     System.out.print((char)data);
17                 }
18             } catch (IOException e) {
19                 e.printStackTrace();
20             }
21         } catch (FileNotFoundException e) {
22             e.printStackTrace();
23         }
24 
25     }
26 }

字符输出：将字符输出至硬盘

核心代码：

扫描二维码关注公众号，回复： 5168409 查看本文章

 1  public static void WriteFile(String address){
 2         FileWriter fileWriter=null;
 3         BufferedWriter bufferedWriter=null;
 4         try {
 5             fileWriter=new FileWriter(new File(address));
 6             bufferedWriter=new BufferedWriter(fileWriter);
 7             bufferedWriter.write("aaaa  bbb");
 8             bufferedWriter.flush();
 9         } catch (IOException e) {
10             e.printStackTrace();
11         }finally {
12             try {
13                 bufferedWriter.close();
14             } catch (IOException e) {
15                 e.printStackTrace();
16             }
17         }
18 
19     }

该程序所有代码:

 1 import java.io.*;
 2 
 3 public class ZiFu {
 4     public static void main(String[] args) {
 5     //ZiFu.ReadFile("D:/temp/temp.txt");
 6         ZiFu.WriteFile("D:/temp1/temp.txt");
 7     }
 8 
 9     public static void WriteFile(String address){
10         FileWriter fileWriter=null;
11         BufferedWriter bufferedWriter=null;
12         try {
13             fileWriter=new FileWriter(new File(address));
14             bufferedWriter=new BufferedWriter(fileWriter);
15             bufferedWriter.write("aaaa  bbb");
16             bufferedWriter.flush();
17         } catch (IOException e) {
18             e.printStackTrace();
19         }finally {
20             try {
21                 bufferedWriter.close();
22             } catch (IOException e) {
23                 e.printStackTrace();
24             }
25         }
26 
27     }
28 
29     public static void ReadFile(String address){
30         FileReader fileReader=null;
31         BufferedReader bufferedReader=null;
32         try {
33             fileReader=new FileReader(new File(address));
34             bufferedReader=new BufferedReader(fileReader);
35             String str=null;
36             try {
37                 while ((str=bufferedReader.readLine())!=null){
38                     System.out.println(str);
39                 }
40             } catch (IOException e) {
41                 e.printStackTrace();
42             }
43         } catch (FileNotFoundException e) {
44             e.printStackTrace();
45         }finally {
46             try {
47                 bufferedReader.close();
48             } catch (IOException e) {
49                 e.printStackTrace();
50             }
51         }
52 
53     }
54 }