Thread: Number Format Exception

Okay, I am in the process of making this program that basically takes the different numbers that are put in, and puts text on the screen depending on which of the two options were selected. HOWEVER, every time i hit calculate, i am getting a Number Format Exception. If anyone could please help me with this i would be greatly appreciative.

package resale_programs;
 
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.NumberFormat;
import java.util.Scanner;
 
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFormattedTextField;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
 
 
public class minToSellGUIVERSION {
 
 
	public static void main(String[] args) {
		resaleGUI g = new resaleGUI();
		g.setBounds(0, 0, 230, 385);
		g.setVisible(true);
		while(g.isVisible()) {};
 
	}
 
 
}
 
class resaleGUI extends JFrame {
 
	private String itemName;
	private int quantity;
	private double pricePerLot;
	private int amountToSell;
	private double amountPerSale;
 
	public resaleGUI() {
		initComponents();
	}
 
	private void calculateButtonPressed(ActionEvent e) {
		resaleGUI newItem = new resaleGUI();
		newItem.getQuantity();
		newItem.pricePerLot();
		newItem.amountToSell();
		newItem.amountPerSale();
		if(comboBox1.getSelectedItem().toString().equals("Profit Reaching Calculator")) {
			label7.setText("You need to sell " + newItem.calcAmount() + " items to reach a profit.");
		}
		else {
			label7.setText("You will make $" + newItem.calcProfit() + " from selling " + amountToSell + " packages!");
		}
	}
 
	private int totalPackages() {
		return quantity%amountToSell >= 1 ? (quantity/amountToSell)+1 : (quantity/amountToSell);
 
	}
 
	private double calcProfit() {
		return pricePerLot - amountPerSale*amountToSell;
	}
 
	private int calcAmount() {
 
		double perPackage = amountPerSale;
		double currentPrice = 0;
		int count = 0;
		while(currentPrice < pricePerLot) {
			currentPrice += perPackage;
			count++;
		}
		return count;
	}
 
	private void amountToSell() {
		amountToSell = Integer.parseInt(textField4.getText());
	}
 
	private void amountPerSale() {
		amountPerSale = Double.parseDouble(textField3.getText());
	}
 
	private void pricePerLot() {
		pricePerLot = Double.parseDouble(textField2.getText());
	}
 
	private void getQuantity() {
		quantity = Integer.parseInt(textField1.getText());
	}
 
	private void initComponents() {
		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
		// Generated using JFormDesigner Open Source Project license - unknown
		comboBox1 = new JComboBox();
		label2 = new JLabel();
		textField1 = new JTextField();
		label3 = new JLabel();
		label4 = new JLabel();
		textField2 = new JTextField();
		label5 = new JLabel();
		textField3 = new JTextField();
		textField4 = new JTextField();
		label6 = new JLabel();
		button1 = new JButton();
		label7 = new JLabel();
 
		//======== this ========
		Container contentPane = getContentPane();
		contentPane.setLayout(null);
 
		//---- comboBox1 ----
		comboBox1.setModel(new DefaultComboBoxModel(new String[] {
			"Profit Reaching Calculator",
			"Profit Calculator"
		}));
		contentPane.add(comboBox1);
		comboBox1.setBounds(new Rectangle(new Point(35, 50), comboBox1.getPreferredSize()));
 
		//---- label2 ----
		label2.setText("Business Calculator");
		label2.setFont(new Font("Times New Roman", Font.PLAIN, 22));
		contentPane.add(label2);
		label2.setBounds(new Rectangle(new Point(20, 15), label2.getPreferredSize()));
		contentPane.add(textField1);
		textField1.setBounds(65, 100, 85, textField1.getPreferredSize().height);
 
		//---- label3 ----
		label3.setText("Quantity of Item:");
		contentPane.add(label3);
		label3.setBounds(new Rectangle(new Point(65, 85), label3.getPreferredSize()));
 
		//---- label4 ----
		label4.setText("Price per lot:");
		contentPane.add(label4);
		label4.setBounds(65, 130, label4.getPreferredSize().width, 15);
		contentPane.add(textField2);
		textField2.setBounds(65, 145, 85, textField2.getPreferredSize().height);
 
		//---- label5 ----
		label5.setText("Your sell price: ");
		contentPane.add(label5);
		label5.setBounds(new Rectangle(new Point(65, 175), label5.getPreferredSize()));
		contentPane.add(textField3);
		textField3.setBounds(65, 190, 85, textField3.getPreferredSize().height);
		contentPane.add(textField4);
		textField4.setBounds(65, 235, 85, textField4.getPreferredSize().height);
 
		//---- label6 ----
		label6.setText("Amount per package:");
		contentPane.add(label6);
		label6.setBounds(new Rectangle(new Point(65, 220), label6.getPreferredSize()));
 
		//---- button1 ----
		button1.setText("Calculate");
		button1.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				calculateButtonPressed(e);
			}
		});
		contentPane.add(button1);
		button1.setBounds(55, 265, 110, button1.getPreferredSize().height);
		contentPane.add(label7);
		label7.setBounds(10, 300, 185, 15);
 
		{ // compute preferred size
			Dimension preferredSize = new Dimension();
			for(int i = 0; i < contentPane.getComponentCount(); i++) {
				Rectangle bounds = contentPane.getComponent(i).getBounds();
				preferredSize.width = Math.max(bounds.x + bounds.width, preferredSize.width);
				preferredSize.height = Math.max(bounds.y + bounds.height, preferredSize.height);
			}
			Insets insets = contentPane.getInsets();
			preferredSize.width += insets.right;
			preferredSize.height += insets.bottom;
			contentPane.setMinimumSize(preferredSize);
			contentPane.setPreferredSize(preferredSize);
		}
		pack();
		setLocationRelativeTo(getOwner());
		// JFormDesigner - End of component initialization  //GEN-END:initComponents
	}
 
	// JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
	// Generated using JFormDesigner Open Source Project license - unknown
	private JComboBox comboBox1;
	private JLabel label2;
	private JTextField textField1;
	private JLabel label3;
	private JLabel label4;
	private JTextField textField2;
	private JLabel label5;
	private JTextField textField3;
	private JTextField textField4;
	private JLabel label6;
	private JButton button1;
	private JLabel label7;
	// JFormDesigner - End of variables declaration  //GEN-END:variables
}

I'm sorry here is the error

Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: ""
	at java.lang.NumberFormatException.forInputString(Unknown Source)
	at java.lang.Integer.parseInt(Unknown Source)
	at java.lang.Integer.parseInt(Unknown Source)
	at resale_programs.resaleGUI.getQuantity(minToSellGUIVERSION.java:93)
	at resale_programs.resaleGUI.calculateButtonPressed(minToSellGUIVERSION.java:48)
	at resale_programs.resaleGUI.access$0(minToSellGUIVERSION.java:46)
	at resale_programs.resaleGUI$1.actionPerformed(minToSellGUIVERSION.java:162)
	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$000(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

i tried throwing in some println's in there before it called each of the textfield values and i am not getting a response

also i changed some code and tried again, this is the new code and the new error

	private void amountToSell() {
		System.out.println(textField4.toString());
		amountToSell = Integer.parseInt(textField4.getText().toString());
	}
 
	private void amountPerSale() {
		System.out.println(textField3.toString());
		amountPerSale = Double.parseDouble(textField3.getText().toString());
	}
 
	private void pricePerLot() {
		System.out.println(textField2.toString());
		pricePerLot = Double.parseDouble(textField2.getText().toString());
	}
 
	private void getQuantity() {
		System.out.println(textField1.toString());
		quantity = Integer.parseInt(textField1.toString());
	}

here is the new error

Exception in thread "AWT-EventQueue-0" javax.swing.JTextField[,65,100,85x20,layout=javax.swing.plaf.basic.BasicTextUI$UpdateHandler,alignmentX=0.0,alignmentY=0.0,border=javax.swing.plaf.BorderUIResource$CompoundBorderUIResource@1050169,flags=296,maximumSize=,minimumSize=,preferredSize=,caretColor=sun.swing.PrintColorUIResource[r=51,g=51,b=51],disabledTextColor=javax.swing.plaf.ColorUIResource[r=184,g=207,b=229],editable=true,margin=javax.swing.plaf.InsetsUIResource[top=0,left=0,bottom=0,right=0],selectedTextColor=sun.swing.PrintColorUIResource[r=51,g=51,b=51],selectionColor=javax.swing.plaf.ColorUIResource[r=184,g=207,b=229],columns=0,columnWidth=0,command=,horizontalAlignment=LEADING]
java.lang.NumberFormatException: For input string: "javax.swing.JTextField[,65,100,85x20,layout=javax.swing.plaf.basic.BasicTextUI$UpdateHandler,alignmentX=0.0,alignmentY=0.0,border=javax.swing.plaf.BorderUIResource$CompoundBorderUIResource@1050169,flags=296,maximumSize=,minimumSize=,preferredSize=,caretColor=sun.swing.PrintColorUIResource[r=51,g=51,b=51],disabledTextColor=javax.swing.plaf.ColorUIResource[r=184,g=207,b=229],editable=true,margin=javax.swing.plaf.InsetsUIResource[top=0,left=0,bottom=0,right=0],selectedTextColor=sun.swing.PrintColorUIResource[r=51,g=51,b=51],selectionColor=javax.swing.plaf.ColorUIResource[r=184,g=207,b=229],columns=0,columnWidth=0,command=,horizontalAlignment=LEADING]"
	at java.lang.NumberFormatException.forInputString(Unknown Source)
	at java.lang.Integer.parseInt(Unknown Source)
	at java.lang.Integer.parseInt(Unknown Source)
	at resale_programs.resaleGUI.getQuantity(minToSellGUIVERSION.java:93)
	at resale_programs.resaleGUI.calculateButtonPressed(minToSellGUIVERSION.java:48)
	at resale_programs.resaleGUI.access$0(minToSellGUIVERSION.java:46)
	at resale_programs.resaleGUI$1.actionPerformed(minToSellGUIVERSION.java:162)
	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$000(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

at java.lang.Integer.parseInt(Unknown Source)
at resale_programs.resaleGUI.getQuantity(minToSellGUI VERSION.java:93)

Can you find the line where the error occurs? What code is on line 93?
What is the argument to the parseInt() method? Is it a String of digits like: "123" or something else?

Look at the code and see what is different about that line compared to the other lines above it that appear to work.

Why are you creating resaleGUI twice? I can see why you create it in the main method, but the reason you are getting these errors is because you are creating a new resaleGUI in the calculateButtonPressed action and trying to convert text from its fields before it is even displayed.

If you remove the line that creates a new resaleGUI in the calculateButtonPressed action and call the subsequent methods on the current resaleGUI object instead, the code will work (kind of).

Among other things, your GUI creation code in the main method is not good. Check out the Java Tutorial HelloWorld example.