如何使用Java代码读取文件的最后几行呢?

读取文件后几行的实现思路

  运行Apache Commons IO的ReversedLinesFileReader
      即可读取File最后几行
  
  具体实现步骤:
    1.引入指定依赖
	2.获取ReversedLinesFileReader对象
	  使用read方法即可读取后几行代码 

pom.xml

<dependency>
		<groupId>commons-io</groupId>
		<artifactId>commons-io</artifactId>
		<version>2.6</version>
	</dependency>

package com.java265.io;
 
import org.apache.commons.io.input.ReversedLinesFileReader;
 
import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Arraylist;
import java.util.List;
 
public class TestReadLastLine {
 
    public static void main(String[] args) {
 
 		//读取test.log的后5行信息
        List<String> lines = readLastLine(new File("D:\\test.log"), 5);
        lines.forEach(x -> System.out.println(x));
    }
 
    public static List<String> readLastLine(File file, int numLastLineToRead) {
        List<String> result = new ArrayList<>();
        try (ReversedLinesFileReader reader = new ReversedLinesFileReader(file, StandardCharsets.UTF_8)) {
 
            String line = "";
            while ((line = reader.readLine()) != null && result.size() < numLastLineToRead) {
                result.add(line);
            }
 
        } catch (IOException e) {
            e.printStackTrace();
        }

        return result;
    }
}