Question

In the Gui need a file in and out writter. That also takes from in file and out file. Write errors to no file found or wrong file. Clear button and Process buttons need to work.

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.Scanner;
import java.io.*;

import javax.swing.*;

@SuppressWarnings("serial")
public class JFileChooserDemo extends JFrame implements ActionListener
{
private JTextField txtInFile;
private JTextField txtOutFile;
private JButton btnInFile;
private JButton btnOutFile;
private JButton btnProcess;
private JButton btnClear;
public JFileChooserDemo()
{
   Container canvas = this.getContentPane();
   canvas.setLayout(new GridLayout (3,1));
     
   canvas.add(createInputFilePanel());
   canvas.add(createOutputFilePanel());
   canvas.add(createButtonPanel());
   this.setVisible(true);
   this.setSize(800, 200);
   this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public JPanel createInputFilePanel()
{
   JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));
   panel.add(new JLabel("In File"));
   txtInFile = new JTextField(60);
   panel.add(txtInFile);
   btnInFile = new JButton("In File");
   panel.add(btnInFile);
   btnInFile.addActionListener(this);
   return panel;
}
  
public JPanel createOutputFilePanel()
{
JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));  
panel.add(new JLabel("Out File"));
txtOutFile = new JTextField(58);
panel.add(txtOutFile);
btnOutFile = new JButton("Out File");
panel.add(btnOutFile);
btnOutFile.addActionListener(this);
return panel;   
}
public JPanel createButtonPanel()
{
   JPanel panel = new JPanel(new FlowLayout(FlowLayout.CENTER));
   btnProcess =new JButton("Process");
   btnProcess.addActionListener(this);
   panel.add(btnProcess);
  
   btnClear =new JButton("Clear");
   btnClear.addActionListener(this);
   panel.add(btnClear);
   return panel;
}
public static void main(String[] args)
{
   new JFileChooserDemo();
   Scanner file = null;
   PrintWriter fout= null;
           try {
               file = new Scanner(new File("numbers.txt"));
               fout = new PrintWriter("TotalSums.txt");
               while(file.hasNext())
               {
                  
                   @SuppressWarnings("resource")
                   Scanner line = new Scanner(file.nextLine());
   int totalSum = 0;
   while (line.hasNext()) {
   int number = line.nextInt();
   totalSum += number;
   fout.print(number);
   if (line.hasNext())
   {
   fout.print("+");
   }
   }
   fout.println("=" + totalSum);
   }
           }
           catch (FileNotFoundException e)
           {
              
               System.out.println("NOT FOUND");
           }
           finally
           {
               if(fout!=null)fout.close();
           }
          
           if(file!=null)file.close();
          
       }
      
      
  
  
public void clearInput()
{
txtInFile.setText(""); txtOutFile.setText("");

}
@Override
public void actionPerformed(ActionEvent e)
{
   if(e.getSource() == btnInFile)
   {
       JFileChooser jfcInFile = new JFileChooser();
       if(jfcInFile.showOpenDialog(this) != JFileChooser.CANCEL_OPTION)
       {
           File inFile = jfcInFile.getSelectedFile();
           txtInFile.setText(inFile.getAbsolutePath());
       }
       else
       {
          
       }
   }
   if(e.getSource() == btnProcess)
   {
       File file = new File(txtInFile.getText());
       try
       {
           Scanner fin = new Scanner(file);
       }
       catch (FileNotFoundException e1)
       {
          
           e1.printStackTrace();
       }
   }
  
}
}

Answer 1

Please find the code below:

JFileChooserDemo.java

package classess6;

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.Scanner;
import java.io.*;

import javax.swing.*;

@SuppressWarnings("serial")
public class JFileChooserDemo extends JFrame implements ActionListener
{
   private JTextField txtInFile;
   private JTextField txtOutFile;
   private JButton btnInFile;
   private JButton btnOutFile;
   private JButton btnProcess;
   private JButton btnClear;
   public JFileChooserDemo()
   {
       Container canvas = this.getContentPane();
       canvas.setLayout(new GridLayout (3,1));

       canvas.add(createInputFilePanel());
       canvas.add(createOutputFilePanel());
       canvas.add(createButtonPanel());
       this.setVisible(true);
       this.setSize(800, 200);
       this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   }
   public JPanel createInputFilePanel()
   {
       JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));
       panel.add(new JLabel("In File"));
       txtInFile = new JTextField(60);
       panel.add(txtInFile);
       btnInFile = new JButton("In File");
       panel.add(btnInFile);
       btnInFile.addActionListener(this);
       return panel;
   }

   public JPanel createOutputFilePanel()
   {
       JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));
       panel.add(new JLabel("Out File"));
       txtOutFile = new JTextField(58);
       panel.add(txtOutFile);
       btnOutFile = new JButton("Out File");
       panel.add(btnOutFile);
       btnOutFile.addActionListener(this);
       return panel;   
   }
   public JPanel createButtonPanel()
   {
       JPanel panel = new JPanel(new FlowLayout(FlowLayout.CENTER));
       btnProcess =new JButton("Process");
       btnProcess.addActionListener(this);
       panel.add(btnProcess);

       btnClear =new JButton("Clear");
       btnClear.addActionListener(this);
       panel.add(btnClear);
       return panel;
   }
   public static void main(String[] args)
   {
       new JFileChooserDemo();
       Scanner file = null;
       PrintWriter fout= null;
       try {
           file = new Scanner(new File("numbers.txt"));
           fout = new PrintWriter("TotalSums.txt");
           while(file.hasNext())
           {

               @SuppressWarnings("resource")
               Scanner line = new Scanner(file.nextLine());
               int totalSum = 0;
               while (line.hasNext()) {
                   int number = line.nextInt();
                   totalSum += number;
                   fout.print(number);
                   if (line.hasNext())
                   {
                       fout.print("+");
                   }
               }
               fout.println("=" + totalSum);
           }
       }
       catch (FileNotFoundException e)
       {

           System.out.println("NOT FOUND");
       }
       finally
       {
           if(fout!=null)fout.close();
       }

       if(file!=null)file.close();

   }

   public void clearInput()
   {
       txtInFile.setText(""); txtOutFile.setText("");

   }
   @Override
   public void actionPerformed(ActionEvent e)
   {
       if(e.getSource() == btnInFile)
       {
           JFileChooser jfcInFile = new JFileChooser();
           if(jfcInFile.showOpenDialog(this) != JFileChooser.CANCEL_OPTION)
           {
               File inFile = jfcInFile.getSelectedFile();
               txtInFile.setText(inFile.getAbsolutePath());
           }
           else
           {

           }
       }

       if(e.getSource() == btnClear)
       {
           txtInFile.setText("");
           txtOutFile.setText("");

       }

       if(e.getSource() == btnOutFile)
       {
           JFileChooser jfcInFile = new JFileChooser();
           if(jfcInFile.showOpenDialog(this) != JFileChooser.CANCEL_OPTION)
           {
               File inFile = jfcInFile.getSelectedFile();
               txtOutFile.setText(inFile.getAbsolutePath());
           }
           else
           {

           }
       }

       if(e.getSource() == btnProcess)
       {
           File file = new File(txtInFile.getText());
           try{
               Scanner fin = new Scanner(file);
               File writerFile = new File(txtOutFile.getText());
               try{
                   PrintWriter writer = new PrintWriter(writerFile);
                   while(fin.hasNextLine()){
                       writer.println(fin.nextLine());
                   }
                   JOptionPane.showMessageDialog(null, "Data exported successfully");
                   writer.close();
               }catch(FileNotFoundException e2){
                   JOptionPane.showMessageDialog(null, "Error!!! File not found+ "+writerFile.getName());  
               }
           }
           catch (FileNotFoundException e1)
           {
               JOptionPane.showMessageDialog(null, "Error!!! File not found+ "+file.getName());
               e1.printStackTrace();
           }
       }

   }
}