Java读取文件

 1 package com;
 2 
 3 import java.io.*;
 4 
 5 /**
 6  * Hello world!
 7  *
 8  */
 9 public class ReadFile
10 {
11     public static void main( String[] args ) {
12         String fileName = "F:/aa.json";
13         String result = readFile(fileName);
14         System.out.println(result);
15     }
16     //FileReader读取字符，可能出现乱码，FileInputStream读取字节,不会出现乱码
17     private static String readFile(String fileName) {
18         StringBuilder sb = new StringBuilder();
19         try {
20             // 创建FileReader对象，用来读取字符流
21             FileReader fileReader =new FileReader(fileName);
22             // 缓冲指定文件的输入
23             BufferedReader bufferedReader = new BufferedReader(fileReader);
24             // 创建FileWriter对象，用来写入字符流
25             FileWriter fileWriter = new FileWriter("F:/response2.json");
26             // 将缓冲对文件的输出
27             BufferedWriter bw = new BufferedWriter(fileWriter);
28             String eachLine;
29             //每次读取一行
30             while ((eachLine=bufferedReader.readLine())!=null){
31                 sb.append(eachLine);
32                 //写一行,需要换行，否则打印在一行，需要close，否则为空
33                 bw.write(eachLine);
34                 bw.newLine();
35             }
36             bw.close();
37 
38         } catch (FileNotFoundException e) {
39             e.printStackTrace();
40         } catch (IOException e) {
41             e.printStackTrace();
42         }
43         return sb.toString();
44     }
45     private String readFileByByte(String fileName){
46         FileInputStream inputStream =new FileInputStream()
47         return
48     }
49 }