Java中使用BufferedReader的readLine()方法和read()方法來讀取文件內容

目標：讀文件

編程時，有很多時候需要讀取本地文件，下面介紹一下讀取方式：

讀單行文件

 

package com;
import java.io.*;
import java.util.ArrayList;
import java.util.List;

import javax.print.DocFlavor.CHAR_ARRAY;

import com.google.common.primitives.Chars;
/*
1、首先創建FileReader對象
2、將FileReader傳遞給BufferedReader
3、采用BufferedReader的readLine()方法和read()方法來讀取文件內容
4、最后一定要的finally語句中關閉BufferedReader15  */
public class MathYsf3{
    public static void main(String[] args){
        BufferedReader br = null;
        BufferedReader br2 = null;
    try {
        br = new BufferedReader(new FileReader("C:\\Users\\91911\\Desktop\\test.txt"));
        // 第一種讀取文件方式
        System.out.println("Reading the file using readLine() method: ");
        String contentLine ;
        List<String> arr1 = new ArrayList<>();
        while ((contentLine = br.readLine()) != null) {
//            contentLine = br.readLine();
            //讀取每一行，並輸出
            System.out.println(contentLine);
            //將每一行追加到arr1
            arr1.add(contentLine);
            }
        //輸出數組
        System.out.println(arr1);
        // 第二種讀取文件方式
        br2 = new BufferedReader(new FileReader("C:\\Users\\91911\\Desktop\\test.txt"));
        System.out.println("Reading the file using read() method: ");
        int num = 0;
        char ch;
        while ((num = br2.read()) != -1) {
            ch = (char) num;
            System.out.print(ch);
            }
        } catch (FileNotFoundException e) { 
            e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
                } finally {
                    try {
                        if (br != null) {
                            br.close();
                            }
                        if (br2 != null) {
                            br2.close();
                            }
                        } catch (IOException e) {
                            System.out.println("Error in closing the BufferedReader");
                            }
            }  
        }    
    }

結果輸出：

from：https://blog.csdn.net/huludan/article/details/54095751