자바 의 간단 한 디지털 처리

import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;

/**
 * 

 * Title:ChangeNumber
 * 
 * 

 * Description:10W   ，5       3   ,    3 。
 * 
 * 

 * Location:Frostburg
 * 
 * 
 * @author: Eric.Chen
 * @date:2017 9 19   10:57:26
 */
public class ChangeNumber {
    public static void main(String[] args) throws IOException {
        // FileReader       
        ChangeNumber re = new ChangeNumber();
    
     FileReader fr = new FileReader("F:\
umber.txt");
        String str = "";
        for (int i = 0; i < 10000; i++) {//           
            char len1 = (char)fr.read();//
            str += len1;
        }
        fr.close();
        String t1 = str;
        String finalNumber = re.cutNumber(t1);//       ，        
        // System.out.println(finalNumber);
        //              
         FileWriter fw = new FileWriter("F:\
ew.txt"); 
        
        char[] charArray = finalNumber.toCharArray();//               
        for (int i = 0; i < charArray.length; i++) {
            fw.write(charArray[i]);//            
            fw.flush();//    

        }
        fw.close();//    
    }

    public String cutNumber(String str)//      ，   3 
    {
        String str1 = str.replaceAll(" ", "");//                  
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < str1.length() - 3; i += 3) {
            String sub = str1.substring(i, i + 3);//   
            sb.append(sub);//   
            sb.append(" ");//      
        }
        String str3 = sb.toString();//          
        return str3;

    }
}