Write a program that reads a group number from a file and shorts the numbers in ascending order and writes the numbers into another file.( File must be save as: File_Read_Write.java)

// Demonstrate CharArrayWriter.

import java.io.*;

class File_Read_Write

{

            public static void main(String args[]) throws IOException

            {

                        CharArrayWriter f = new CharArrayWriter();

                        char c,t;

                        int b,i=0,p,k,d;

                        int a[]=new int[50];

                        //String s = "This should end up in the array";

                        FileReader fr = new FileReader("file1.txt");

                        BufferedReader br = new BufferedReader(fr);

                        String s="",s1="",s2="";

                        while((b = br.read()) != -1)

                        if(b>47&&b<58)

                        a[i++]=b-48;

                        //s1=s1+a[2];

                        for(p=1;p<i;p++)

                        {

                        for(k=p;k<i;k++)

                        if(a[p-1]>a[k])

                        {

                                    d=a[p-1];

                                    a[p-1]=a[k];

                                    a[k]=d;

                                    s1=s1+a[p-1];

                                    s2=s2+k;

                        }

            }

                        for(k=0;k<i;k++)

                        s=s+a[k];

                        char buf[] = new char[s.length()];

                        s.getChars(0, s.length(), buf, 0);

                        f.write(buf);

                        /*//System.out.println("Buffer as a string");

                        //System.out.println(f.toString());

                        //System.out.println("Into array");

                        char c[] = f.toCharArray();

                        for (int i=0; i<c.length; i++)

                        {

                                    System.out.print(c[i]);

                        }

                        System.out.println("\\nTo a FileWriter()");*/

                        FileWriter f2 = new FileWriter("test.txt");

                        f.writeTo(f2);

                        f2.close();

                        System.out.println("Doing a reset");

                        f.reset();

                        for (int l=0; l<3; l++)

                        f.write('X');

                        System.out.println(s);

            }

}

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