java - 用扫描仪回显文本文件并将其设为双倍行距？

Question

我必须创建一个 EchoDouble 类来扩展 Echo 类，后者将文本文件回显到控制台。

这个文本文件的内容是

Nature's first green is gold, 
Her hardest hue to hold. 
Her early leaf's a flower; 
But only so an hour. 

但我正在尝试编辑 EchoDouble 类中的 processLine 方法，以便它会像这样回显双倍行距的文本文件

Nature's first green is gold, 

Her hardest hue to hold. 

Her early leaf's a flower; 

But only so an hour. 

回声等级

 import java.util.Scanner;
 import java.io.*;

    public class Echo{
      String fileName; // external file name
      Scanner scan; // Scanner object for reading from external file

      public Echo(String f) throws IOException
      {
        fileName = f;
        scan = new Scanner(new FileReader(fileName));
      }

      // reads lines, hands each to processLine
      public void readLines(){
        while(scan.hasNext()){
          processLine(scan.nextLine());
        }
        scan.close();
      }

      // does the real processing work
      public void processLine(String line){
        System.out.println(line);
      }
    }

EchoDouble 类

import java.io.*;

public class EchoDouble extends Echo
{
  public EchoDouble (String datafile) throws IOException
  {
    super(datafile);
  }

  // Prints the given line and inserts a blank line
  // Overrides the processLine method in Echo class
  public void processLine(String line)
  {
    /* **code here** */
  }
}

我是 java 中的这个回显和扫描仪的新手，并且被困在这个问题上。如果有人可以就如何解决这个问题给我任何建议，我们将不胜感激!

Answer 1

这个怎么样:

@Override
public void processLine(String line){
     System.out.println(line);
     System.out.println();
}