Object[] options1 = { "Try This Number", "Choose A Random Number","Quit" };


JPanel panel = new JPanel();
panel.add(new JLabel("Enter number between 0 and 1000"));
JTextField textField = new JTextField(10);
panel.add(textField);

int result = JOptionPane.showOptionDialog(null, panel, "Enter a Number",
JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE,null, options1, null);
if (result == JOptionPane.YES_OPTION){
JOptionPane.showMessageDialog(null, textField.getText());
}

the question is
how do I put an if statement for "Try This Number", "Choose A Random Number","Quit"

google "java random number" and you will find many code snippets dealing with random numbers. The java documentation is also excellent. Search it.