day19/LineNumberReaderDemo.java

/*java.lang.Object  |--java.io.Reader      |--java.io.BufferedReader          |--java.io.LineNumberReaderLineNumberReader 类中特有的方法：setLineNumber(int)设置当前行号getLineNumber()获取当前行号*/import java.io.*;class LineNumberReaderDemo{public static void main(String[] args) throws IOException{FileReader fr = new FileReader("ZhuangShiSheJi.java");LineNumberReader lnr = new LineNumberReader(fr);//LineNumberReader是BufferedReader的子类String line = null;lnr.setLineNumber(100);//设置当前行号while((line=lnr.readLine())!=null){System.out.println(lnr.getLineNumber()+line);//获取当前行号}lnr.close();}}