Getting this error this is testing button clicked Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: "" at java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:67)
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import java.awt.FlowLayout;
import java.awt.Font;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
public class ImageOperation {
public static void operate(int key)
{
JFileChooser fileChooser=new JFileChooser();
fileChooser.showOpenDialog(null);
File file=fileChooser.getSelectedFile();
//file FileInputStream
try
{
FileInputStream fis=new FileInputStream(file);
byte []data=new byte[fis.available()];
fis.read(data);
int i=0;
for(byte b:data)
{
System.out.println(b);
data[i]=(byte)(b^key);
i++;
}
FileOutputStream fos=new FileOutputStream(file);
fos.write(data);
fos.close();
fis.close();
JOptionPane.showMessageDialog(null, "Done");
}catch(Exception e)
{
e.printStackTrace();
}
}
public static void main(String[] args) {
System.out.println("this is testing");
JFrame f=new JFrame();
f.setTitle("Image Operation");
f.setSize(400,400);
f.setLocationRelativeTo(null);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Font font=new Font("Roboto",Font.BOLD,25);
//creating button
JButton button=new JButton();
button.setText("Open Image");
button.setFont(font);
//creating text field
JTextField textField=new JTextField(10);
textField.setFont(font);
button.addActionListener(e->{
System.out.println("button clicked");
String text=textField.getText();
int temp=Integer.parseInt(text);
operate(temp);
});
f.setLayout(new FlowLayout());
f.add(button);
f.add(textField);
f.setVisible(true);
}
}
