Java读取文件的简单实现方法

import java.io.*;public class FileToString {   public static String readFile(String fileName) {    String output = "";     File file = new File(fileName);    if(file.exists()){      if(file.isFile()){        try{          BufferedReader input = new BufferedReader (new FileReader(file));          StringBuffer buffer = new StringBuffer();          String text;          while((text = input.readLine()) != null)            buffer.append(text +"/n");          output = buffer.toString();                  }        catch(IOException ioException){          System.err.println("File Error!");        }      }      else if(file.isDirectory()){        String[] dir = file.list();        output += "Directory contents:/n";                for(int i=0; i<dir.length; i++){          output += dir[i] +"/n";        }      }    }    else{      System.err.println("Does not exist!");    }    return output;   }   public static void main (String args[]){     String str = readFile("C:/1.txt");     System.out.print(str);   }}