Java中的IO操作 字符流：FileReader和 FileWriter

Posted 2020-10-19 ztt_tttt

 FileReader和 FileWriter  读写字符串

 1 package object.io;
 2 
 3 import java.io.BufferedReader;
 4 import java.io.BufferedWriter;
 5 import java.io.FileReader;
 6 import java.io.FileWriter;
 7 import java.io.IOException;
 8 
 9 public class FileWrite {
10 
11     public static void main(String[] args) throws IOException {
12         // TODO Auto-generated method stub
13         FileReader reader=new FileReader("D:\\\\Program Files (x86)\\\\io\\\\fileWriter.txt"); 
14         BufferedReader bReader=new BufferedReader(reader);
15         FileWriter writer=new FileWriter("D:\\\\Program Files (x86)\\\\io\\\\fileWriter2.txt");
16         BufferedWriter bWriter=new BufferedWriter(writer);
17         String content="";
18         //readLine一行一行的读取
19         while((content=bReader.readLine())!=null){
20             //\\r\\n换行
21             bWriter.write(content+"\\r\\n");
22         }
23         /**
24          * 关闭流的顺序：
25          *     当A依赖B的时候先关闭A，再关闭B
26          *     带缓冲的流最后关闭的时候会执行一次flush
27          */
28         reader.close();
29         bReader.close();
30         bWriter.close();
31         writer.close();
32         
33     }
34 
35 }

　　操作结果：

　　

 

练习：

 

 

 1 package object.io;
 2 
 3 import java.io.BufferedReader;
 4 import java.io.BufferedWriter;
 5 import java.io.FileNotFoundException;
 6 import java.io.FileReader;
 7 import java.io.FileWriter;
 8 import java.io.IOException;
 9 
10 public class FileWrite2 {
11 
12     public static void main(String[] args) throws IOException {
13         // TODO Auto-generated method stub
14         FileReader reader=new FileReader("D:\\\\Program Files (x86)\\\\io\\\\fileWriter11.txt"); 
15         BufferedReader bReader=new BufferedReader(reader);
16         FileWriter writer=new FileWriter("D:\\\\Program Files (x86)\\\\io\\\\fileWriter22.txt");
17         BufferedWriter bWriter=new BufferedWriter(writer);
18         String content="";
19         while((content=bReader.readLine())!=null){
20             if(content.contains("{title}")){
21                 content=content.replace("{title}", "放假");
22             }
23             if(content.contains("{description}")){
24                 content=content.replace("{description}", "元旦放假三天");
25             }
26             bWriter.write(content+"\\r\\n");
27         }
28         /**
29          * 关闭流的顺序：
30          *     当A依赖B的时候先关闭A，再关闭B
31          *     带缓冲的流最后关闭的时候会执行一次flush
32          */
33         reader.close();
34         bReader.close();
35         bWriter.close();
36         writer.close();
37         
38     }
39 
40 }

结果：