使用Java读取.txt文件？

Question

I am creating the following program, which reads a text.file and print out certain things based on the arguments that are given. If the user inputs "run Profile text.txt", I would like it to print out the file line by line. If the user inputs "run Profile text.txt 5", the first 5 lines should be printed out. I have the following program written:

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

public class Profile{

  public static String file;
  public static int len;
  public static Profile a;
  public static Profile b;

  //Method to read whole file
  static void wholeFile(String file){
    Scanner in = new Scanner(file);
    int lineNumber = 1;

    while(in.hasNextLine()){
      String line = in.nextLine();
      System.out.println("/* " + lineNumber + " */ " + line);
      lineNumber++;
    }
    in.close();
  }

  //Method to read file with line length
  static void notWholeFile(String file, int len){
    Scanner in = new Scanner(file);
    int lineNumber = 1;

    while(in.hasNextLine() && lineNumber <= len){
      String line = in.nextLine();
      System.out.println("/* " + lineNumber + " */ " + line);
      lineNumber++;
    }
    in.close();
  }

Profile(String file){
    this.file = file;
}
Profile(String file, int len){
    this.file = file;
    this.len = len;
    notWholeFile(file, len);
}
  public static void main(String[] args){
    Scanner in = new Scanner (System.in);
    if (args.length == 1){
      file = args[0] + "";
      a = new Profile(file);
      wholeFile(file);
    }     
    if (args.length == 2){
      file = args[0] + "";
      len = Integer.parseInt(args[1]);
      b = new Profile(file, len);
      notWholeFile(file, len);
    }   
  }
}

For testing purposes, I have included a .txt file in my directory by the name of "text.txt", which contains the following text:

blah blah blah blah blah blah blah
blah blah blah blah blah blah blah

blah blah blah blah blah blah blah
blah blah blah blah blah blah blah

blah blah blah blah blah blah blah
blah blah blah blah blah blah blah

blah blah blah blah blah blah blah
blah blah blah blah blah blah blah

I am a beginner with java but believe there shouldn't be any mistakes. However, when I input "run Profile text.txt 5", I get the following output:

> run Profile text.txt 5
/* 1 */ text.txt
/* 1 */ text.txt
> 

Why can I not get the "blah blah" lines to print out? Is there an error with the way I am reading the .txt file? How can I access the lines inside of this text file? Any advice will be helpful.

Answer 1

You are scanning the name of the file, not the contents of the file. That is:

Scanner in = new Scanner(file);  // where file is of type string

creates a Scanner that reads from the String itself. Try something like:

Scanner in = new Scanner(new File(file));

This should read the contents of the file.