import java.io.*;

// A binary stream is a series of data type values

// To read and write to them you use different methods

// based on the type of data that you are using

public class JavaLesson33{

public static void main(String[] args){

// Create an array of type Customer

Customer[] customers = getCustomers();

// A DataOutputStream allows you to print

// primitive data types to a file

DataOutputStream custOutput = createFile("/Users/rickeyhrabowskie/Documents/workspace/Java Code/src/customers.dat");

// Enhanced for loop for arrays

// Cycles through all of the people in the customers array

for(Customer person : customers){

createCustomers(person, custOutput);

}

// Closes the connection to the DataOutputStream

try {

custOutput.close();

} catch (IOException e) {

System.out.println("An I/O Error Occurred");

// Closes the program

System.exit(0);

}

getFileInfo();

}

// class that defines all the fields for my customers

private static class Customer{

public String custName;

public int custAge;

public double custDebt;

public boolean oweMoney;

public char custSex;

// constructor that's called when a customer is made

public Customer(String custName, int custAge, double custDebt, boolean oweMoney, char custSex){

this.custName = custName; // String

this.custAge = custAge; // Integer

this.custDebt = custDebt; // Double

this.oweMoney = oweMoney; // Boolean

this.custSex = custSex; // Character

}

}

// Creates an array of Customer Objects

private static Customer[] getCustomers(){

Customer[] customers = new Customer[5];

customers[0] = new Customer("John Smith", 21, 12.25, true, 'M');

customers[1] = new Customer("Sally Smith", 30, 2.25, true, 'F');

customers[2] = new Customer("Paul Ryan", 21, 0, false, 'M');

customers[3] = new Customer("Mark Jacobs", 21, 3.25, true, 'M');

customers[4] = new Customer("Steve Nash", 21, 5.25, true, 'M');

return customers;

}

// Create the file and the DataOutputStream that will write to the file

private static DataOutputStream createFile(String fileName){

try{

// Creates a File object that allows you to work with files

// on the hard drive. There is no difference between File

// for character or binary stream writing, or reading

File listOfNames = new File(fileName);

// FileOutputStream is used to write streams of data to a file

// You define whether a new file is created versus appended

// to based on if you add a boolean to the FileOutputStream

// FileOutputStream(file, true) : Appends to the file

// FileOutputStream(file, false) : Creates a new file

// BufferedOutputStream gathers all the data and then writes

// it all at one time (Speeds up the Program)

// DataOutputStream is used to write primitive data to the file

DataOutputStream infoToWrite = new DataOutputStream(

new BufferedOutputStream(

new FileOutputStream(listOfNames)));

return infoToWrite;

}

// You have to catch this when you call FileWriter

catch(IOException e){

System.out.println("An I/O Error Occurred");

// Closes the program

System.exit(0);

}

return null;

}

// Create a string with the customer info and write it to the file

private static void createCustomers(Customer customer, DataOutputStream custOutput){

try{

// Write primitive data to the file

// Writes a String in UTF format

custOutput.writeUTF(customer.custName);

// Writes an Integer

custOutput.writeInt(customer.custAge);

// Writes a Double

custOutput.writeDouble(customer.custDebt);

// Writes a Boolean

custOutput.writeBoolean(customer.oweMoney);

// Writes a Character

custOutput.writeChar(customer.custSex);

// You also have writeByte, writeFloat, writeLong

// and writeShort

}

catch(IOException e){

System.out.println("An I/O Error Occurred");

System.exit(0);

}

}

// Read info from the file and write it to the screen

private static void getFileInfo(){

System.out.println("Info Written to File\n");

// Open a new connection to the file

File listOfNames = new File("/Users/derekbanas/Documents/workspace3/Java Code/src/customers.dat");

boolean eof = false;

try {

// A DataInputStream object has the methods for reading the data

// The BufferedInputStream gathers the data in blocks

// FileInputStream gets data from the file

DataInputStream getInfo = new DataInputStream(

new BufferedInputStream(

new FileInputStream(listOfNames)));

// Using a while loop that pulls data until EOFException is thrown

while (!eof){

// You have to read data in the exact order it was put in the file

String custName = getInfo.readUTF();

int custAge = getInfo.readInt();

double custDebt = getInfo.readDouble();

boolean oweMoney = getInfo.readBoolean();

char custSex = getInfo.readChar();

System.out.println(custName);

System.out.println(custAge);

System.out.println(custDebt);

System.out.println(oweMoney);

System.out.println(custSex + "\n");

}

} // END OF TRY

catch (EOFException e) {

eof = true;

}

// Can be thrown by FileInputStream

catch (FileNotFoundException e) {

System.out.println("Couldn't Find the File");

System.exit(0);

}

catch(IOException e){

System.out.println("An I/O Error Occurred");

System.exit(0);

}

}

}