**Hello i am a noob when it comes to java so sorry if its obvious but the code below is giving me a error when i try to compile it, the error is: Exception in thread "main" java.lang.Error: Unresolved compilation problem: at goodcalculator.main(goodcalculator.java:127). Can anyone help me?
**
CODE:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

class goodcalculator extends JFrame {

    JButton add, subtract, multiply, divide;
    JtextField num1, num2;
    JLabel result, enter1, enter2;

    public goodcalculator() {
        setLayout (new GridBagLayout());
        GridBagConstraints c =new GridBagConstraints();

        enter1 = new JLabel("1st: ");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 0;
        add(enter1, c);

        num1 = new JTextField(10);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 0;
        c.gridwidth = 3;
        add(num1, c);

        enter2 = new JLabel ("2nd: ");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 1;
        c.gridwidth = 1;
        add(enter2, c);

        num2 = new JTextField(10);
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 1;
        c.gridwidth = 3;
        add(num2, c);

        add = new JButton("+");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 2;
        c.gridwidth = 1;
        add(add, c);

        subtract = new JButton("-");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 1;
        c.gridy = 2;
        add(subtract, c);

        multiply = new JButton ("*");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 2;
        c.gridy = 2;
        add(multiply, c);

        divide = new JButton("/");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 3;
        c.gridy = 2;
        add(divide, c);

        result = new JLabel("");
        c.fill = GridBagConstraints.HORIZONTAL;
        c.gridx = 0;
        c.gridy = 4;
        c.gridwidth = 4;
        add(result, c);

        event a = new event();
        add.addActionListener(a);
        subtract.addActionListener(a);
        multiply.addActionListener(a);
        divide.addActionListener(a);        
    }

    public class event implements ActionListener {
        public void actionPreformed(ActionEvent a) {
            double number1, number2;

            try {
                number1 = Double.parseDouble(num1.getText());               
            } catch (NumberFormatException e) {
                result.setText("Illegal characters in first field");
                result.setForeground(Color.RED);
                return;
            }

            try {
                number2 = Double.parseDouble(num2.getTexr());
            } catch (NumberFormatException e) {
                result.setText("Illegal characters in second field");
                result.setForeground(Color.RED);
                return;
            }

            String op = a.getActionCommand();

            if(op.equals("+")) {
                double sum = number1 + number2;
                result.setText(number1 + "+" + number2 + "=" + sum);
                result.setForeground(Color.RED);                
            } else if(op.equals("-")) {
                double diff = number1 - number2;
                result.setText(number1 + "-" + number2 + "=" + diff);
                result.setForeground(Color.RED);                
            } else if(op.equals("*")) {
                double factor = number1 * number2;
                result.setText(number1 + "*" + number2 + "=" + factor);
                result.setForeground(Color.RED);
            } else if(op.equals("/")) {
                if(number2 == 0) {
                    result.setText("Cannot divide by zero");
                    result.setForeground(Color.RED);
                } else {
                    double quotient = number1 / number1;
                    result.setText(number1 + "/" + number2 + "=" + quotient);
                    result.setForeground(Color.RED);
                }
            }
        }
    }
    public static void main(String[] args) {
        goodcalculator gui = new goodcalculator();
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);
        gui.setSize(250,175);
        gui.setTitle("My very first java calculator");
    }
}

That means you tried to run the program when it still had error(s) that prevent it from compiling.
In Eclipse look for the little red x at the left of the code, red underlining under the code in question, and a red block in the vertical scroll bar to show you where to look. The text of the compiler message will appear when you hover the mouse over the rex x or the underlined code, or you can see all the messages in the Problems tab at the bottom of the screen.
At your level of experience it's probably not a good idea to use Eclipse - it's a tool for experts and is just going to add a lot more stuff to your learning curve. Consider using a programmmer's editor and the command line compiler javac for the moment.

Just check the spelling. Go through the whole code. Check the classes and initiation of variables. Will work.

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