Question

Please answer this question using Java programming.

(a) Write a method textFilter(String binaryName, String textName) of a class Filters which reads the binary byte file with name binaryName, removes all non-printable bytes (which are bytes with values < 32 or > 127) and outputs the remaining bytes to an ASCII text file with name textName. Handle possible exception(s) by outputting a suitable message using the getMessage() method if an exception occurs.


(b) What is the possible exception when the following statement is executed?

System.out.println("This is the first argument: " + args[0]);

Answer 1

COMMENT IF YOU HAVE ANY DOUBTS AND LIKE THE ANSWER.

Answer for question a)

/**
* File Name : TextFilter.java
*
*/
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.OutputStream;

public class TextFilter {

   /**
   * Method that takes two file names binaryName and textName as params
   * and then writes the printable characters into textName file as assci chars.
   *
   * @param binaryName
   * @param textName
   */
   public static void textFilter(String binaryName,String textName) {
       try {
           InputStream inp = new FileInputStream(binaryName);
           BufferedWriter bw = new BufferedWriter(new FileWriter(new File(textName)));
           int byteRead = inp.read();
           char byteToChar;
           while(byteRead != -1) {
               if(byteRead >=32 && byteRead <=127) {
                   byteToChar = (char)byteRead;
                   bw.write(byteToChar+"");
               }
               byteRead = inp.read();
           }
           bw.close();
           inp.close();
       }catch(Exception e) {
           System.out.println("Exception occured: "+e.getMessage());
       }
   }
   /**
   * An extra method added to write binary values -128 to 127 to passed file
   * as Byte data.
   * @param binaryName
   */
   public static void writeAllAsciiCharsToFile(String binaryName) {
       try {
           OutputStream out = new FileOutputStream(binaryName);
           for(Integer i = 1;i<=256;i++) {
               //values > 127 will automatically convert to negative values.
               //as it reaches the byte range by using byteValue() method.
               out.write(i.byteValue());
               System.out.println(i.byteValue());
           }
           out.close();
       }catch(Exception e) {
           System.out.println("Exception occured: "+e.getMessage());
       }
   }
   public static void main(String[] args) {
      
       String binaryName = "binaryData.txt";
       String textName="assciData.txt";
       textFilter(binaryName,textName);
//       writeAllAsciiCharsToFile("binaryData.txt");
      
      
   }
}

(b) What is the possible exception when the following statement is executed?

System.out.println("This is the first argument: " + args[0]);

ANSWER:

It throws ArrayOutOfBounds Exception, because if you didn't pass any arguments to the main method , then args array is empty and you are going to access 0_th index value in an empty array which results Array Index Out Of Bounds Exception.