How do I create a Data folder in my C: Drive using my Java program

[Xavier Downing]

My assignment requires that I use exception handling to create a directory and file if necessary.

I was able to create a C:Data\inventory.dat file, provided that there's an existing Data folder (directory) in my C: drive; however, I have a feeling that the assignment wants me to create an actual Data folder if one is not available. When I remove the Data folder from my C: drive, I get "C:\data\inventory.dat (The system cannot find the path specified)".

How am I to create able a folder that currently does not exist? I'm reading the java.sun website on the File class, the mkdirs methods, and the FileSystemView class; however, I'm having trouble implementing the requirements in my code (I wish API documentation was more understandable to me.). Can an example be provided? Thank you everyone.

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.HeadlessException;
import java.awt.Image;
 
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.Serializable;
 
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
 
 
public class InventoryGUI extends JFrame implements ActionListener,Serializable 
{
   private JTextArea textArea;
   
   private JButton first,
   next,
   previous,
   last,
   add,
   modify,
   delete,
   save,
   search,
   exit;
   
   JLabel imageLabel;
   
   private static Inventory inv = new Inventory();
 
   /**
 * @param arg0
 * @throws HeadlessException
 */
   public InventoryGUI( String arg0 ) throws HeadlessException 
   {
  super( "Inventory GUI" );
  
  textArea = new JTextArea( 250,30 );
 
  JScrollPane scrollPane = new JScrollPane( textArea ); 
 
  textArea.setEditable( false );
 
  scrollPane.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_ALWAYS );
 
  scrollPane.setPreferredSize( new Dimension( 250, 250 ) );
 
  JPanel cp = new JPanel();
 
  cp.setSize( 250, 40 );
 
  cp.setLayout( new BorderLayout() );
 
  cp.add( scrollPane,BorderLayout.CENTER );
  
  JPanel buttonPaenl = new JPanel();
  
  JPanel buttonPaenl1 = new JPanel();
 
  first = new JButton( "First" );
  first.addActionListener( this );
  
  search = new JButton( "Search" );
  search.addActionListener( this );
  
  next = new JButton( "Next" );
  next.addActionListener( this );
 
  previous = new JButton( "Previous" );
  previous.addActionListener( this );
 
  last = new JButton( "Last" );
  last.addActionListener( this );
 
  add = new JButton( "Add" );
  add.addActionListener( this );
 
  modify = new JButton( "Modify" );
  modify.addActionListener( this );

  delete = new JButton( "Delete" );
  delete.addActionListener( this );
 
  save = new JButton( "Save" );
  save.addActionListener( this );
 
  exit = new JButton( "Exit" );
  exit.addActionListener( this );

  buttonPaenl.setLayout( new FlowLayout() );
  buttonPaenl1.setLayout( new FlowLayout() );
  buttonPaenl.add( first );
  buttonPaenl.add( previous );
  buttonPaenl.add( next );
  buttonPaenl.add( last );
  buttonPaenl1.add( add );
  buttonPaenl1.add( modify );
  buttonPaenl1.add( delete );
  buttonPaenl1.add( save );
  buttonPaenl1.add( search );
  buttonPaenl1.add( exit );
 
  cp.add( buttonPaenl,BorderLayout.SOUTH );
  cp.add( buttonPaenl1,BorderLayout.NORTH );
 
  ImageIcon icon = new ImageIcon( "logo.gif" );
  imageLabel = new JLabel( icon, JLabel.CENTER );
  cp.add( imageLabel, BorderLayout.EAST );
  this.setContentPane( cp );
 
  this.setTitle( " Week Nine Final Project: Inventory Program Part Six - Transformers Autobot Inventory ( More Than Meets the Eye o_0?! ) " );
 
  this.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
  this.textArea.setText(inv.getFirst());
  this.setSize(400, 400);
  this.pack();
  this.setVisible( true );
   }
 
   @Override
   public void actionPerformed( ActionEvent e ) 
   {
  // TODO Auto-generated method stub
  if( e.getActionCommand().equals( "First" ) )
  {
 textArea.setText( inv.getFirst() );
  }
  
  if( e.getActionCommand().equals( "Next" ) )
  {
 textArea.setText(inv.getNext());
  }

  if( e.getActionCommand().equals( "Previous" ) )
  {
 textArea.setText( inv.getPrevious() );
  }
  
  if( e.getActionCommand().equals( "Last" ) )
  {
 textArea.setText(inv.getLast());
  }
  
  if( e.getActionCommand().equals( "Save" ) )
  {
 save();
  }

  if( e.getActionCommand().equals( "Exit" ) )
  {
 System.exit(0);
  }

  if( e.getActionCommand().equals( "Add" ) ) 
  {
 InventoryDialogue id = new InventoryDialogue( true," Add a new Inventory " );
  }
  
  if( e.getActionCommand().equals( "Modify" ) )
  {
 InventoryDialogue id = new InventoryDialogue( false," Modify Inventory " );
  }
  
  if( e.getActionCommand().equals( "Search" ) )
  {
 String s = JOptionPane.showInputDialog( null, " Enter Product Name ",null, 1 );
 
 s = inv.Search(s);
 
 if( s == null )
 {
JOptionPane.showMessageDialog( this, " No Results Found " );
 } 

 else textArea.setText( s );
  }

  if( e.getActionCommand().equals( "Delete" ) )
  {
 inv.getproducts().remove( inv.index );
  }
  
   }
   
   public void save()
   {
  File f = new File( "C:\\data\\inventory.dat" );
  
  try 
  {  
 FileOutputStream out = new FileOutputStream( f );
 
 try 
 {
ObjectOutputStream objectOut = new ObjectOutputStream( out );
   objectOut.writeObject( inv );
 } 
 
 catch (IOException e) 
 {
// TODO Auto-generated catch block
JOptionPane.showMessageDialog( null, e.getMessage() );
   e.printStackTrace();
 }
  } 
  
  catch ( FileNotFoundException e ) 
  {
 // TODO Auto-generated catch block
 JOptionPane.showMessageDialog( null, e.getMessage() );
e.printStackTrace();
  }
 
   }  
 
   public static Inventory getInv() 
   {
  return inv;
   }
 
   public static void setInv( Inventory inv ) 
   {
  InventoryGUI.inv = inv;
   }
 
   /**
* @param args
*/
   public static void main( String[] args ) 
   {
  InventoryGUI inventory = new InventoryGUI( "Inventory" );
   }
}

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.LayoutManager;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
 
 
public class InventoryDialogue extends JFrame implements ActionListener
{
   private boolean status = false; //false is for modify
   
   JTextField nameTextField,
  unitTextField,
  priceTextField;
   
   JLabel nameLabel,
  unitLabel,
  priceLabel;

   JPanel TextFields,
  buttons;
   
   JButton modify, 
   add;

   public InventoryDialogue( Boolean stat, String title )
   {
  super( title );
  status = stat;
  JPanel but = new JPanel();
  modify = new JButton( "Modify" );
  modify.addActionListener( this );
  add = new JButton( "Add" );
  add.addActionListener( this );
  but.add( add );
  but.add( modify );
  
  if( status == false )
  {
 add.setVisible( false );
  }
  
  else
  {
 modify.setVisible( false );
  }
  
  nameTextField = new JTextField( "", 20 );
  unitTextField = new JTextField( "", 5 );
  priceTextField = new JTextField( "" , 5 );
  nameLabel = new JLabel( "Name" );
  unitLabel = new JLabel( "Units" );
  priceLabel = new JLabel( "Price per Unit" );
  JPanel p = new JPanel();
 
  p.setLayout( new FlowLayout() );
  p.add( nameLabel );
  p.add( nameTextField );
  p.add( unitLabel );
  p.add( unitTextField );
  p.add( priceLabel );
  p.add( priceTextField );
  JPanel cp = new JPanel();
  cp.setLayout( new BorderLayout() );
  cp.add( p, BorderLayout.CENTER );
  cp.add( but, BorderLayout.EAST );
  this.setContentPane( cp );
  this.setDefaultCloseOperation( JFrame.DISPOSE_ON_CLOSE );
  this.pack();
  this.setVisible( true );
   }
 
   @Override
   public void actionPerformed( ActionEvent arg0 ) 
   {
  if( arg0.getActionCommand().equals( "Add" ) )
  {
 String name;
 int units;
 Double price;
 name = nameTextField.getText();
  
 try 
 {
units = Integer.parseInt( unitTextField.getText() );
 } 
  
 catch ( NumberFormatException e ) 
 {
JOptionPane.showMessageDialog( null, e.getMessage() );
 
e.printStackTrace();
 
return;
 }
  
 try 
 {
price = Double.parseDouble( priceTextField.getText() );
 } 
  
 catch ( NumberFormatException e ) 
 {
// TODO Auto-generated catch block
JOptionPane.showMessageDialog( null, e.getMessage() );
 
e.printStackTrace();
 
return;
 }

 InventoryGUI.getInv().getproducts().add( new ProductModified( name, InventoryGUI.getInv().products.size(), 
   units,price ) );
  
 this.dispose();
  }
 
  if( arg0.getActionCommand().equals( "Modify" ) )
  {
 String name;
 int units;
 Double price;
 name = nameTextField.getText();
  
 try 
 {
units = Integer.parseInt( unitTextField.getText() );
 } 
  
 catch ( NumberFormatException e ) 
 {
JOptionPane.showMessageDialog( null,"Please Enter Valid Integers" );
 
e.printStackTrace();
 
return;
 }

 try 
 {
price = Double.parseDouble( priceTextField.getText() );
 } 
  
 catch ( NumberFormatException e ) 
 {
// TODO Auto-generated catch block
JOptionPane.showMessageDialog( null,"Please Enter Valid Price" );
 
//e.printStackTrace();
return;
 }

 InventoryGUI.getInv().getproducts().set( InventoryGUI.getInv().index, 
new ProductModified( name, InventoryGUI.getInv().index, units, price ) );

 this.dispose();
  }
 
   }
   
   public static void main( String args[] )
   {
  InventoryDialogue idf = new InventoryDialogue( true,"cc" );
   }
}

import java.text.Collator;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.Locale;
import java.io.Serializable;
 
public class Inventory implements Serializable
{
   private String inventoryName; // name of inventory
   
   public String restockRate; // restock rate percentage
   
   public double totalRestock;
 
   public static int index;
 
   public ArrayList < ProductModified > products = new ArrayList < ProductModified > ();
 
   public Inventory()
   {
  products.add( new ProductModified( "No Sale Bot", 0, 1, 0.00 ) );
  products.add( new ProductModified( "Optimus Prime", 7, 52, 160.00 ) );
  products.add( new ProductModified( "BumbleeBee", 16, 61, 97.00 ) );
  products.add( new ProductModified( "Ironhide", 25, 106, 88.00 ) );
  products.add( new ProductModified( "Ratchet", 34, 125, 79.00 ) );
  products.add( new ProductModified( "Jazz", 0, 124, 70.00 ) );
  
  index = 0;
   }

   public void sort()
   {
  Locale loc = Locale.ENGLISH;
   
  ProductModified Temp;
   
  Collator col = Collator.getInstance( loc );
   
  for ( int i = 0; i < products.size(); i++ ) 
  {
 for ( int j = i + 1; j < products.size(); j++ )
 {
if( col.compare( products.get( i ).getAutobotName(), products.get( j ).getAutobotName() ) > 0 )
{
   Temp = products.get( i );

   products.set( i, products.get( j ) );
   products.set( j, Temp );
}
 }
  }
   }

   public String getInventoryName() 
   {
  return inventoryName;
   }

public void setInventoryName( String inventoryName ) 
{
   this.inventoryName = inventoryName;
}

public String getRestockRate() 
{
   return restockRate;
}

public void setRestockRate( String restockRate ) 
{
   this.restockRate = restockRate;
}

public double getTotalRestock() 
{
   return totalRestock;
}

public void setTotalRestock( double totalRestock ) 
{
   this.totalRestock = totalRestock;
}

public ArrayList < ProductModified > getproducts() 
{
   return products;
}

public void seproducts( ArrayList < ProductModified > products) 
{
   this.products = products;
}

public String toString()
{
   String transformersSub = new String(" ");
 
   transformersSub = "Welcome to the\n" + getInventoryName() + "!\n\n";
 
   transformersSub = transformersSub + "Below is the available inventory:\n\n";
 
   transformersSub = transformersSub + "The restock interest rate is at " + getRestockRate() + ".\n\n";
 
   transformersSub = transformersSub + "Index\tProductModified #\t\t\tName\t\tUnits\t\tPrice\t\t";
 
   transformersSub = transformersSub + "Unit Restock Value\t";
 
   transformersSub = transformersSub + "Stock Value\t\t";
 
   transformersSub = transformersSub + "Total ProductModified Restock\n";
   
   Iterator < ProductModified > i = this.getproducts().iterator();
   
   while(i.hasNext())
   {
  transformersSub = transformersSub + i.next();
   }
   
  return transformersSub;
   }
   
   public Double getTotal()
   {
  Double Total = 0.0;
  
  ProductModified p;
  
  Iterator < ProductModified > i = products.iterator();
  
  while( i.hasNext() )
  {
p = i.next();

Total = Total + p.getPrice() * p.getUnit();
  }
  
  return Total;
   }
 
   public String processOutPut( ProductModified p )
   {
  String out = "Welcome to the Transformers Autobot Toy Inventory\n\nTotal Inventory = " 
  + this.getTotal() + "\nRestocking Fee = 5%" 
  + "\n\nItem #\tName\tUnit\tPrice\tUnit Restock Value" 
  + p;
  
  return out;
   }
   
   public String getFirst()
   {
  index = 0;
  
  return processOutPut( products.get(0) );

   }
   
   public String getLast()
   {
  index = products.size() - 1;
  
  return processOutPut( products.get( products.size() - 1 ) );
   }

   public String getNext()
   {
  if( index == products.size() - 1 ) 
  {
 getFirst();
  
 return getFirst();
  } 
  
  else
  {
 index++;
 
 return processOutPut( products.get( index ) );
  }
   }
   
   public String getPrevious()
   {
  if( index == 0 )
  {
 return getLast();
  } 
  
  else

  return processOutPut(products.get(--index));
   }
   
   public String Search( String Search )
   {
  Iterator < ProductModified > i = products.iterator();
   
  String te = null;
   
  ProductModified p;
  
  while( i.hasNext() )
  {
 p = i.next();
  
 if( p.getAutobotName().equals( Search ) )
 {
te = processOutPut( p );
 }
  }
  
  return te;
   }
}
 

import static java.lang.System.out;
import java.io.Serializable;
 
//class declaration for TransformersProduct
public class Product implements Serializable
{
   public String autobotName; // array of autobot toy names
   public int productNumber; // product # array ID for product
   public int unit; // array of autobot toy units
   public double price; // array of autobot prices
   public double inventoryValue;

   /**
* @param autobotName
* @param productNumber
* @param unit   
* @param price
*/
   
   public Product( String autobotName, int productNumber, int unit,
   double price ) 
   {
  super();
  this.autobotName = autobotName;
  this.productNumber = productNumber;
  this.unit = unit;
  this.price = price;
   }
 
   public String getAutobotName() 
   {
  return autobotName;
   }
   
   public void setAutobotName( String autobotName ) 
   {
  this.autobotName = autobotName;
   }
 
   public int getProductNumber() 
   {
  return productNumber;
   }

   public void setProductNumber( int productNumber ) 
   {
  this.productNumber = productNumber;
   }
   
   public int getUnit() 
   {
  return unit;
   }
   
   public void setUnit( int unit ) 
   {
  this.unit = unit;
   }
   
   public double getPrice() 
   {
  return price;
   }
   
   public void setPrice( double price ) 
   {
  this.price = price;
   }

   public double getInventoryValue() 
   {
  return inventoryValue;
   }

   public Double inventoryValue()
   {
  return this.getPrice() * this.getUnit();
   }
   
   public String toString()
   {
  return "\n"+this.productNumber+"\t"+this.autobotName+"\t"+this.unit +"\t"+this.price+ "\t"; 
   }
}

import java.io.Serializable;
 
public class ProductModified extends Product implements Serializable
{
   public ProductModified( String autobotName, int productNumber, int unit,
   double price ) 
   {
  super( autobotName, productNumber, unit, price );
  this.inventoryValue = this.inventoryValue();
  // TODO Auto-generated constructor stub
   }

   public Double inventoryValue()
   {
  return this.getUnit() * this.getPrice() + this.getUnit() * this.getPrice() * 0.05;
   }
   
   public String toString()
   {
  return "\n" + this.productNumber + "\t" + this.autobotName 
  + "\t" + this.unit + "\t" + this.price + "\t" 
  + this.getInventoryValue(); 
   }
}

[David O'Meara]

Please don;t post the same question in multiple forums.

Dave