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Urgent Problem Regarding I/O

 
sameershintrein
Greenhorn
Posts: 1
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hi all,
I got stuck with some I/O related program in Java.Actually this program is same as in Deitel's book. But after running the program i am getting not getting the data in the output file project.dat properly. Also i tried to retrieve the data from the file using the second program but it is also displaying the blank data in the textfield. I am not getting WHY???.
Can anyone help me urgently regarding the same.Please guide me wich class i have to use.
waiting for reply.
thanx in advance.
regards,
sameer
here are the two programs
//this program is to store the data in a file project.dat
import java.io.*;
import java.awt.*;
import java.awt.event.*;
public class ttt extends Frame implements ActionListener{
private TextField accountField,firstNameField,lastNameField,balanceField;
private Button enter,done,next;
static String sum;
int a,b;
private DataOutputStream output;
private DataInputStream input;
public ttt()
{
super("create client file");
try{
output=new DataOutputStream(new FileOutputStream("project.dat"));
//input=new DataInputStream(new FileInputStream("project1.dat"));
}
catch(IOException e)
{
//System.err.println("file not opened properly",+ e.toString());
System.exit(1);
}
setSize(300,150);
setLayout(new GridLayout(5,2));
add(new Label("�ccoount no"));
accountField=new TextField();
add(accountField);
add(new Label("First name"));
firstNameField=new TextField(20);
add(firstNameField);
add(new Label("Last Name"));
lastNameField=new TextField(20);
add(lastNameField);
add(new Label("Balance"));
balanceField=new TextField(20);
add(balanceField);
enter=new Button("enter");
enter.addActionListener(this);
add(enter);
done=new Button("done");
done.addActionListener(this);
add(done);

setVisible(true);
}
public void addRecord()
{
int accountNumber=0;
Double d;
if(!accountField.getText().equals(""))
{
try
{
accountNumber=Integer.parseInt(accountField.getText());
if(accountNumber>0)
{

output.writeInt(accountNumber);
output.writeUTF(firstNameField.getText());
output.writeUTF(lastNameField.getText());
d=new Double(balanceField.getText());
output.writeDouble(d.doubleValue());
}
accountField.setText("");
firstNameField.setText("");
lastNameField.setText("");
balanceField.setText("");
}
catch(NumberFormatException nfe)
{
System.err.println("u must enter an in value");
}
catch(IOException io)
{
System.err.println("err during writing a file");
System.exit(1);
}
}
}
/*public void readRecord()
{
int account;
String first,last;
double balance;
try{
account=input.readInt();
first=input.readUTF();
last=input.readUTF();
balance=input.readDouble();
accountField.setText(String.valueOf(account));
firstNameField.setText(first);
lastNameField.setText(last);
balanceField.setText(String.valueOf(balance));
}
catch(EOFException ef)
{
closeFile();
}
catch(IOException e)
{
System.out.println("ghfhfgf");
System.exit(1);
}
}*/
/*private void closeFile()
{
try{
input.close();
System.exit(0);
}
catch(IOException e)
{
System.out.println("ghfhfgf");
System.exit(1);
}
}*/
public void actionPerformed(ActionEvent e)
{
addRecord();
if(e.getSource()==done)
{
try
{
output.close();
}
catch(IOException io)
{
System.err.println("file not closed properly"+io.toString());
}
System.exit(0);
}
}
public static void main(String args[])
{
new ttt();
}
}

and second:
//this file is to retrieve the data from the file project.dat
import java.io.*;
import java.awt.*;
import java.awt.event.*;
public class ttt1 extends Frame implements ActionListener{
private TextField accountField,firstNameField,lastNameField,balanceField;
private Button enter,done,next;
static String sum;
int a,b;
private DataInputStream input;
public ttt1()
{
super("create client file");
try{
input=new DataInputStream(new FileInputStream("project.dat"));
}
catch(IOException e)
{
//System.err.println("file not opened properly",+ e.toString());
System.exit(1);
}
setSize(300,150);
setLayout(new GridLayout(5,2));
add(new Label("Last Name"));
lastNameField=new TextField(20);
add(lastNameField);
add(new Label("Balance"));
balanceField=new TextField(20);
add(balanceField);
enter=new Button("enter");
enter.addActionListener(this);
add(enter);
done=new Button("done");
done.addActionListener(this);
add(done);
next=new Button("next");
done.addActionListener(this);
add(next);

setVisible(true);
}

public void readRecord()
{
int account;
String first,last;
double balance;
try{
account=input.readInt();
first=input.readUTF();
last=input.readUTF();
balance=input.readDouble();
accountField.setText(String.valueOf(account));
firstNameField.setText(first);
lastNameField.setText(last);
balanceField.setText(String.valueOf(balance));
}
catch(EOFException ef)
{
closeFile();
}
catch(IOException e)
{
System.out.println("Exception");
System.exit(1);
}
}
private void closeFile()
{
try{
input.close();
System.exit(0);
}
catch(IOException e)
{
System.out.println("ghfhfgf");
System.exit(1);
}
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==next)
readRecord();
else
closeFile();
}
public static void main(String args[])
{
new ttt1();
}
}
 
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