/*
  Author  : Michael Robinson
  Program : filesBinary.java
  Purpose : This program 
            creates a binary files
            writes data to it
            closes file and then
            opens the binary file, 
            reads and displays the contents.
           
  Updated : Jan 29, 2099
*/


import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.EOFException; 
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;


public class filesBinary
{    
    //create numbers.dat binary file if it does not exist
    public static void createBinaryFile( int numbers[] ) 
                       throws IOException
    {
        //accepted array to be written to a file:
        //int numbers[] = { 2, 4, 6, 8, 10, 12, 14 };
           	      
        //create the binary outputBinary object
        //if file exists it appends data to it
        //else creates a new file, done by true parameter.
        FileOutputStream outputBinary = new       
                         FileOutputStream( "numbers.dat", true );

        //creates the outputBinFile object to write data into
        //the numbers.dat binary file 
        DataOutputStream outputBinFile = new 
                         DataOutputStream( outputBinary );
                              
        System.out.println( "Writing the numbers to the file..." );
    
        //write the array elements into the numbers.dat binary file    
        for( int i = 0; i < numbers.length; i++ )
        {
            outputBinFile.writeInt( numbers[i] );
            System.out.print( numbers[i] + " " );
        }
                
        //outputBinFile.writeChars("\n");
        System.out.println( "\nDone." );
               	                   	      
        //close the file.
        outputBinFile.close();   
                   
    }//end public static void createBinaryFile()
                        	   
                  	
    //opens and reads all records in numbers.dat binary file 
    public static void openReadBinaryFile( int numbersLength ) 
                       throws IOException
    {       
        int number = 0;             //number read from the file
        boolean endOfFile = false;  //EOF flag
                 	      
        //Create the inputBinary object to help in reading the 
        //numbers.dat binary file
        FileInputStream inputBinary  =  new          
                        FileInputStream( "numbers.dat" );

        //Create the inputBFile object to be able to use the previous 
        //inputBinary object to read the numbers.dat binary file
        DataInputStream inputBFile = new 
                        DataInputStream( inputBinary );
                   	    
        System.out.println( "\nReading numbers from Binary file:" );
                  
        //read and display all the records in the numbers.dat file.    
        while( !endOfFile )
        {
            try
            {
                for( int x = 0; x < numbersLength; x++ )
                {
	            number = inputBFile.readInt();      //read record 
                    System.out.printf( "%d ", number ); //display record 
                }  
                System.out.println();
            }
            catch ( EOFException e )
            {
                endOfFile = true;
            }
             
        }//end public static void openReadBinaryFile( int 
         //numbersLength ) throws IOException
            
        System.out.println( "\nDone." );
	        	      
        //close the file
        inputBFile.close();   
        	   
    }//end public static void openReadBinaryFile() throws IOException
       		
        		
    public static void main( String args[] ) throws IOException
    {   
        //create array to be written into numbers.dat binary file
        int numbers[] = { 2, 4, 6, 8, 10, 12, 14 };
           
        //create numbers.dat binary file and write array data into it
        createBinaryFile( numbers ); 

        //open, read and display all data in numbers.dat binary file 
        openReadBinaryFile( numbers.length );   
                  
    }//end public static void main(String[] args) throws IOException
         
}//end public class filesBinary