使用LineNumberReader逐行读取文本文件

代码（1.8的语法）：

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.LineNumberReader;

public class TestLineFileReader {
    public static void main(String[] args) {
        try (LineNumberReader lineNumberReader = new LineNumberReader(new FileReader("D:\\logs\\test.txt"));){
            String line = null;

            while ((line = lineNumberReader.readLine()) != null) {
                System.out.println("Line " + lineNumberReader.getLineNumber() +": " + line);
            }
        } catch (FileNotFoundException ex) {
            ex.printStackTrace();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

输出：

Line 1: while i<9 {
Line 2:   sum=sum+1 // hello
Line 3:   i=i+1
Line 4: }
Line 5:
Line 6: sum=sum+1

--END-- 2019-11-19 13:50