Java 快速按行读取文件

起因：Java的IO总是很繁琐，而且需要你显式地处理IO抛出的异常，在一般的脚本化处理起来非常麻烦。每次仅仅是需要一个需求，那就是——快速按行读取文件，但是总是要查半天！

记录一下快速的按行读取文件的代码。
我们知道Python什么的很好用：open --> read... read... -> close就好了，而JAVA很烦。

传统的

private static void readFile2(File fin) throws IOException {
    // Construct BufferedReader from FileReader
    BufferedReader br = new BufferedReader(new FileReader(fin));
 
    String line = null;
    while ((line = br.readLine()) != null) {
        System.out.println(line);
    }
 
    br.close();
}

try with resource

File file = new File("F:\\dogData\\VCF2Tree\\eGPS_result_ydl20190902\\sample.csv");
try (BufferedReader br = new BufferedReader(new FileReader(file));) {
        String line = null;
        while ((line = br.readLine()) != null) {
            System.out.println(line);
        }

  } catch (IOException e) {
    e.printStackTrace();
}

java8

Charset charset = Charset.forName("US-ASCII");
try (BufferedReader reader = Files.newBufferedReader(file, charset)) {
    String line = null;
    while ((line = reader.readLine()) != null) {
        System.out.println(line);
    }
} catch (IOException x) {
    System.err.format("IOException: %s%n", x);
}

第三方库

import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.IOException;
import java.util.List;

public class ReadTextFile {

    public static void main(String[] args) throws IOException {

        try {

            File f = new File("src/com/mkyong/data.txt");

            System.out.println("Reading files using Apache IO:");

            List<String> lines = FileUtils.readLines(f, "UTF-8");

            for (String line : lines) {
                System.out.println(line);
            }

        } catch (IOException e) {
            e.printStackTrace();
        }

    }

}