LineNumberReaderDemo

import java.io.*;

class LineNumberReaderDemo
{
public static void main(String[] args)throws IOException
{
FileReader fr = new FileReader(“PersonDemo.java”);

	LineNumberReader lnr = new LineNumberReader(fr);

	String line = null;
	lnr.setLineNumber(100);
	while((line=lnr.readLine())!=null)
	{
		System.out.println(lnr.getLineNumber()+":"+line);
	}

	lnr.close();
}

}

//练习：模拟一个带行号的缓冲区对象。