2020-12-08 c5515644963e7428f2a6e08e94ff8f68 99+ 2 分钟 0.3 k 0次访问

开始学Java之21 读取文件

好难。。

第一种 Scanner

import java.io.*;
import java.util.Scanner;
public class ReadText  {
    String message;
    public static void main(String[] args)throws IOException {
        String message;
        Scanner scan = new Scanner ( new File("data\\small.txt"));
        while (scan.hasNext()){
          message = scan.nextLine();
           System.out.println(message); 
        }
    }
}

第二种 BufferedReader

import java.io.FileReader;
import java.io.BufferedReader;

public class ReadMe {
  public static void main(String[] args) throws java.io.IOException {
    BufferedReader br = new BufferedReader(new FileReader("data\\small.txt"));
    StringBuilder sb = new StringBuilder();
    String line = br.readLine();
    while (line != null) {
      // sb.append(line).append("\n");
      sb.append(line);
      line = br.readLine();
    }
    String fileAsString = sb.toString();
    System.out.println(fileAsString);

  }
}

BufferedReader 的另外一种


import java.io.FileReader;
import java.io.BufferedReader;
import java.io.File;

public class ReadAnotherText {
  public static void main(String[] args) throws java.io.IOException {
    File mytext = new File("data\\small.txt");
    FileReader fr = new FileReader(mytext);
    // BufferedReader br = new BufferedReader(new FileReader("data\\small.txt"));
    BufferedReader br = new BufferedReader(fr);
    StringBuilder sb = new StringBuilder();
    String line = br.readLine();
    while (line != null) {
      // sb.append(line).append("\n");
      sb.append(line);
      line = br.readLine();
    }
    String fileAsString = sb.toString();
    System.out.println(fileAsString);

  }
}