Problems with this weeks code..Still not understanding Illegal start of expression...HELP PLEASE

[LeeAnne Murphy]

/*
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package mortcalcjp2week3;

//Declaration for imported swings, text, and awt's used throughout program
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.text.DecimalFormat;
import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
	//End of class

public class Mortcalcjp2week3 {

     
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        
//  Requestor - Ninfa Pendleton - Rapid City, SD
//  PRG/421
//  August 22, 2011

//  Service Request SR-mf-003 Mortgage Payment Calculator.  Change Request #4:Write the program in Java (with a graphical
//  user interface) and have it calculate and display the mortgage payment amount from user input of the amount of the mortgage
//  and the user's selection from a menu of available mortgage loans:
	 
//	- 7 years at 5.35%
//	- 15 years at 5.5%
//	- 30 years at 5.75%
	 
//  Use an array for the mortgage data for the different loans. Display the mortgage payment amount followed by
//  the loan balance and interest paid for each payment over the term of the loan. Allow the user to loop
//  back and enter a new amount and make a new selection or quit. Please insert comments in the program to
//  document the program.

    private int term;
    private double rate;
    private double principal;
		}
        
    public class MortCalc extends JFrame implements ActionListener{
  
   
		int term = 0;
		double principal = 0;
		double rate = 0;
		double monthlyPayment = 0;
		double interest = 0;
	 
	DecimalFormat twodigits = new DecimalFormat("#,###.00");
	 
	//***Create JPanels and Make JLabels and JTextFields***
		JPanel row1 = new JPanel();
		JLabel mortgage_label = new JLabel("Mortgage Calculator", JLabel.CENTER);
	 
		JPanel row2 = new JPanel(new GridLayout(1, 2));
		JLabel principal_label = new JLabel("Net Amount $",JLabel.LEFT);
		JTextField principal_txt = new JTextField(10);
	 
		JPanel row3 = new JPanel(new GridLayout(1, 2));
		JLabel term_label = new JLabel("Term (Yrs)",JLabel.LEFT);
		JTextField term_txt = new JTextField(10);
	 
		JPanel row4 = new JPanel(new GridLayout(1, 2));
		JLabel rate_label = new JLabel("Interest Rate (%)", JLabel.LEFT);
		JTextField rate_txt = new JTextField(10);
	 
		JPanel row5 = new JPanel(new GridLayout(1, 2));
		JLabel payment_label = new JLabel("Monthly Payment $", JLabel.LEFT);
		JTextField payment_txt = new JTextField(10);
	 
	//***Create JButtons and FlowLayout***
		JPanel button = new JPanel(new FlowLayout(FlowLayout.LEFT, 10, 10));
		JButton clearButton = new JButton("Reset");
		JButton exitButton = new JButton("Exit");
		JButton calcButton = new JButton("Calculate");
		JButton loan01Button = new JButton("Loan_#01");
		JButton loan02Button = new JButton("Loan_#02");
		JButton loan03Button = new JButton("Loan_#03");
	 
	//***Create JTextArea and JScrollPane***
		JTextArea displayArea = new JTextArea(10, 45);
		JScrollPane scroll = new JScrollPane(displayArea);
	 
	public MortCalc()
	{
	//***Provide a Super Class and Title for Program***
		super("Mortgage Calculator SR-MF-003 #5");
	}
	//***Create JMenuBar and Populate it with Commands***
		public JMenuBar createMenuBar()
	{
	//***Create JMenuBar***
		JMenuBar mnuBar = new JMenuBar();
		setJMenuBar(mnuBar);
	 
	//***Create JMenuBar add File***
		JMenu mnuFile = new JMenu("File", true);
		mnuFile.setMnemonic(KeyEvent.VK_F);
		mnuFile.setDisplayedMnemonicIndex(0);
		mnuBar.add(mnuFile);
	 
	//***Create JMenuBar add File & Exit***
		JMenuItem mnuFileExit = new JMenuItem("Exit");
		mnuFileExit.setMnemonic(KeyEvent.VK_F);
		mnuFileExit.setDisplayedMnemonicIndex(1);
		mnuFile.add(mnuFileExit);
		mnuFileExit.setActionCommand("Exit");
		mnuFileExit.addActionListener(this);
	 
	//***Create JMenuBar add Function***
		JMenu mnuFunction = new JMenu("Function", true);
		mnuFunction.setMnemonic(KeyEvent.VK_F);
		mnuFunction.setDisplayedMnemonicIndex(0);
		mnuBar.add(mnuFunction);
	 
	//***Create JMenuBar add Function & Clear***
		JMenuItem mnuFunctionClear = new JMenuItem("Clear");
		mnuFunctionClear.setMnemonic(KeyEvent.VK_F);
		mnuFunctionClear.setDisplayedMnemonicIndex(1);
		mnuFunction.add(mnuFunctionClear);
		mnuFunctionClear.setActionCommand("Clear");
		mnuFunctionClear.addActionListener(this);
	 
	//***Create JMenuBar add Function & Fill***
		JMenu mnuFunctionAutoFill = new JMenu("Auto Fill");
		mnuFunctionAutoFill.setMnemonic(KeyEvent.VK_F);
		mnuFunctionAutoFill.setDisplayedMnemonicIndex(2);
		mnuFunction.add(mnuFunctionAutoFill);
	 
	//***Create JMenuBar add Function & Fill Amount1***
		JMenuItem mnuFunctionAutoFillAmount1 = new JMenuItem("Loan_#01");
		mnuFunctionAutoFillAmount1.setMnemonic(KeyEvent.VK_F);
		mnuFunctionAutoFillAmount1.setDisplayedMnemonicIndex(3);
		mnuFunctionAutoFill.add(mnuFunctionAutoFillAmount1);
		mnuFunctionAutoFillAmount1.setActionCommand("Loan_#01");
		mnuFunctionAutoFillAmount1.addActionListener(this);
	 
	//***Create JMenuBar add Function & Fill Amount2***
		JMenuItem mnuFunctionAutoFillAmount2 = new JMenuItem("Loan_#02");
		mnuFunctionAutoFillAmount2.setMnemonic(KeyEvent.VK_F);
		mnuFunctionAutoFillAmount2.setDisplayedMnemonicIndex(4);
		mnuFunctionAutoFill.add(mnuFunctionAutoFillAmount2);
		mnuFunctionAutoFillAmount2.setActionCommand("Loan_#02");
		mnuFunctionAutoFillAmount2.addActionListener(this);
	 
	//***Create JMenuBar add Function & Fill Amount3***
		JMenuItem mnuFunctionAutoFillAmount3 = new JMenuItem("Loan_#03");
		mnuFunctionAutoFillAmount3.setMnemonic(KeyEvent.VK_F);
		mnuFunctionAutoFillAmount3.setDisplayedMnemonicIndex(5);
		mnuFunctionAutoFill.add(mnuFunctionAutoFillAmount3);
		mnuFunctionAutoFillAmount3.setActionCommand("Loan_#03");
		mnuFunctionAutoFillAmount3.addActionListener(this);
	 
	//***Create JMenuBar add Function & Calculate****
		JMenuItem mnuFunctionCalculate = new JMenuItem("Calculate");
		mnuFunctionCalculate.setMnemonic(KeyEvent.VK_F);
		mnuFunctionCalculate.setDisplayedMnemonicIndex(6);
		mnuFunction.add(mnuFunctionCalculate);
		mnuFunctionCalculate.setActionCommand("Calculate");
		mnuFunctionCalculate.addActionListener(this);
	 
	//***Create JMenuBar add Function & Amortize Payments***
		JMenuItem mnuFunctionAmortizePayments = new JMenuItem("Amortize Payments");
		mnuFunctionAmortizePayments.setMnemonic(KeyEvent.VK_F);
		mnuFunctionAmortizePayments.setDisplayedMnemonicIndex(7);
		mnuFunction.add(mnuFunctionAmortizePayments);
		mnuFunctionAmortizePayments.setActionCommand("Amortize Payments");
		mnuFunctionAmortizePayments.addActionListener(this);
	 
	//***Create JMenuBar add Info***
		JMenu mnuInfo = new JMenu("Info", true);
		mnuInfo.setMnemonic(KeyEvent.VK_E);
		mnuInfo.setDisplayedMnemonicIndex(0);
		mnuBar.add(mnuInfo);
	 
	//***Create JMenuBar add Info & About***
		JMenuItem mnuInfoAbout = new JMenuItem("About");
		mnuInfoAbout.setMnemonic(KeyEvent.VK_E);
		mnuInfoAbout.setDisplayedMnemonicIndex(1);
		mnuInfo.add(mnuInfoAbout);
		mnuInfoAbout.setActionCommand("About");
		mnuInfoAbout.addActionListener(this);
	 
	//***Adjust JFrame Size and Close-Operations***
		setSize(800,600);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		Container pane = getContentPane();
		Border rowborder = new EmptyBorder( 3, 10, 3, 10 );// Sets Border Size
	 
	//***Set Pane and Row Properties***
		pane.add(row1);
		row1.add(mortgage_label);
		row1.setMaximumSize( new Dimension( 10000, row1.getMinimumSize().height));
		row1.setBorder( rowborder);
	 
		pane.add(row2);
		row2.add(principal_label);
		row2.add(principal_txt);
		row2.setMaximumSize( new Dimension( 10000, row2.getMinimumSize().height));
		row2.setBorder( rowborder);
	 
		pane.add(row3);
		row3.add(term_label);
		row3.add(term_txt);
		row3.setMaximumSize( new Dimension( 10000, row3.getMinimumSize().height));
		row3.setBorder( rowborder);
	 
		pane.add(row4);
		row4.add(rate_label);
		row4.add(rate_txt);
		row4.setMaximumSize( new Dimension( 10000, row4.getMinimumSize().height));
		row4.setBorder( rowborder);
	 
		pane.add(row5);
		row5.add(payment_label);
		row5.add(payment_txt);
		payment_txt.setEnabled(false);
		row5.setMaximumSize( new Dimension( 10000, row5.getMinimumSize().height));
		row5.setBorder( rowborder);
	 
	 
		button.add(calcButton);
		button.add(clearButton);
		button.add(exitButton);
		pane.add(button);
		button.setMaximumSize( new Dimension( 10000, button.getMinimumSize().height));
	 
		scroll.setBorder(BorderFactory.createEmptyBorder(10,10,10,10));
		pane.add(scroll);
	 
		pane.setLayout(new BoxLayout( pane, BoxLayout.Y_AXIS));
		setVisible(true);
		setContentPane(pane);
	 
	//***Add Listeners***
		clearButton.addActionListener(this);
		exitButton.addActionListener(this);
		calcButton.addActionListener(this);
		loan01Button.addActionListener(this);
		loan02Button.addActionListener(this);
		loan03Button.addActionListener(this);
	 
	return mnuBar;// End JMenuBar Creation
	}
	
	
	//***Create commands for JMenuBar***
        @Override
	public void actionPerformed(ActionEvent event)
	{
	
	 Object source = event.getSource();
	        //Begin "if" function
	        if (source == calcButton) // calculates on hit
	        {
	            validateUserInput(principal_txt, rate_txt, term_txt); // validates input
	 
	            //formula for calculation output
	            monthlyPayment = principal * (rate / (12 * 100)) / (1 - Math.pow(1 + (rate / (12 * 100)), -1 * (term * 12)));
	            payment_txt.setText("" + twodigits.format(monthlyPayment));
	        }
	 
	        if (source == clearButton) // Clears on hit
	        {
	            term_txt.setText("  ");
	            rate_txt.setText("  ");
	            principal_txt.setText("   ");
	            payment_txt.setText("   ");
	            displayArea.setText("   ");
	        }
	 
	        if (source == exitButton) // Exits on hit
	        {
	 
	            System.exit(0);
			}
	 
	    }//end action
	 
	  
	    }
	    //Declaration of user input for each variable
	 
	    public void validateUserInput(JTextField principal_txt, JTextField rate_txt, JTextField term_txt) {
	        //Begin "try/catch" function
	        try {
	 
	            principal = Double.parseDouble(principal_txt.getText());
	 
	        } catch (NumberFormatException e)//Action listener
	        {
	            //Function to validate if input is from user is numeric and if not output error message
	            JOptionPane.showMessageDialog(null, "Enter Numeric Value Only for Net!", "INVALD ENTRY", JOptionPane.ERROR_MESSAGE);
	        }
	 
			try {
	 
	            term = Integer.parseInt(term_txt.getText());
	        } catch (NumberFormatException e) {
	 
	 
	            JOptionPane.showMessageDialog(null, "Enter Numeric Value Only for Term!", "INVALD ENTRY", JOptionPane.ERROR_MESSAGE);
	        }
	 
	        try {
	 
	            rate = Double.parseDouble(rate_txt.getText());
	        } catch (NumberFormatException e) {
	 
	            JOptionPane.showMessageDialog(null, "Enter Numeric Value Only for Rate!", "INVALD ENTRY", JOptionPane.ERROR_MESSAGE);
	        }
	    }
	}

[Maneesh Godbole]

So where are you getting the error? Can you post the stack trace?

[LeeAnne Murphy]

Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - illegal start of expression
at mortcalcjp2week3.Mortcalcjp2week3.main(Mortcalcjp2week3.java:58)
Java Result: 1
BUILD SUCCESSFUL (total time: 3 seconds)

I know it is in line 58 which is this part but I am so lost.


/**
* @param args the command line arguments
*/
public static void main(String[] args) {

// Requestor - Ninfa Pendleton - Rapid City, SD
// PRG/421
// August 22, 2011

// Service Request SR-mf-003 Mortgage Payment Calculator. Change Request #4:Write the program in Java (with a graphical
// user interface) and have it calculate and display the mortgage payment amount from user input of the amount of the mortgage
// and the user's selection from a menu of available mortgage loans:

// - 7 years at 5.35%
// - 15 years at 5.5%
// - 30 years at 5.75%

// Use an array for the mortgage data for the different loans. Display the mortgage payment amount followed by
// the loan balance and interest paid for each payment over the term of the loan. Allow the user to loop
// back and enter a new amount and make a new selection or quit. Please insert comments in the program to
// document the program.

private int term;
private double rate;
private double principal;
}



Can you explain what the stack trace is?

[Maneesh Godbole]

		private int term;
		private double rate;
		private double principal;

Does it make sense to declare these variables inside the main and mark them private? When do they go out of scope? You declare them as private; private to what?

[LeeAnne Murphy]

It was placed there by Netbeans IDE 7.0, if I don't have them up there then the lower part of the code errors on me.

[Maneesh Godbole]

If you are a beginner, I would strongly recommend agains any IDEs. That is the best way to learn Java and not the IDE.

If you move the variables, you won't get any errors, but your application won't run either because your main method will be empty.

[LeeAnne Murphy]

I understand that but the instructor for the class wants us to use the IDE. So that is where I am at. I will keep trying to figure it out.

Thank you for the help.

[Michael Brush]

The above posters were correct. You need to move lines 59-62 up to around line 35 to get it above the main method. You will then get the error from the IDE, but if you add

new Mortcalcjp2week3().new MortCalc();

to your main method, that part should be resolved. That instantiates your inner class and gives main something to do.

[fred rosenberger]

Did you write all this code?

If so, this is a BAD idea. I never, Never, NEVER write more than 2-3 lines before I try to compile. You have over 300. That is a recipe for disaster.

Now...

When someone said "print the stack trace", they meant "print out the exact and full text of the error you are getting." If I take your code and try to compile it from the command line (fyi, I took out the package statement to make that a little easier for me), I get the following:

C:\slop>javac Mortcalcjp2week3.java
Mortcalcjp2week3.java:54: illegal start of expression
private int term;
^
Mortcalcjp2week3.java:303: class, interface, or enum expected
public void validateUserInput(JTextField principal_txt, JTextField rate_
txt, JTextField term_txt) {
^
Mortcalcjp2week3.java:309: class, interface, or enum expected
} catch (NumberFormatException e)//Action listener
^
Mortcalcjp2week3.java:313: class, interface, or enum expected
}
^
Mortcalcjp2week3.java:318: class, interface, or enum expected
} catch (NumberFormatException e) {
^
Mortcalcjp2week3.java:322: class, interface, or enum expected
}
^
Mortcalcjp2week3.java:327: class, interface, or enum expected
} catch (NumberFormatException e) {
^
Mortcalcjp2week3.java:330: class, interface, or enum expected
}
^
8 errors

The most important thing is to always focus on the first error. There is something about that line it doesn't like. I decided to simplify things even more. I got rid of EVERYTHING except your main method. That leaves me with this:

public class Mortcalcjp2week3a {
    public static void main(String[] args) {
       private int term;
       private double rate;
       private double principal;
       }
}

So looking at this, you declare these variable to be private (which only makes sense instance variables), but these are method variables. Private just makes no sense here.

These variables need to either NOT be marked private, or declared outside of main, as member variables.

and as an aside, you'll notice your main method doesn't DO anything. That's probably not right either.

[Grayson Churchel]

I'm a noob here but I think I've spotted the problem in your code:
public static void main(String[] args) {
should be:
public static void main(String args[]) {
It's an array of String objects and not an object of type String Array.
I always like to start my debugging by looking for simple and silly mistakes I've made.

[Matthew Brown]

Grayson Churchel wrote:I'm a noob here but I think I've spotted the problem in your code:
public static void main(String[] args) {
should be:
public static void main(String args[]) {
It's an array of String objects and not an object of type String Array.
I always like to start my debugging by looking for simple and silly mistakes I've made.

Hi Grayson. Welcome to The Ranch!

Actually, no, that's not an error. Both are valid syntax, although personally I think String[] args is better style, as I think it better represents the meaning - i.e. "args is a variable of type array-of-Strings".

With the introduction of var-arg methods in Java 5, public static void main(String... args) is also valid.

The main error is as Fred says.

[Grayson Churchel]

Well this has been educational.
main(String[] args) is OK.
private variables in main is a no-no.
Good to know.

[Naishadh Parmar]

You may create an instance of your class in the main() method and put all the variables outside the main() method.
So it may look like this:

 
    private int term;   
    private double rate;   
    private double principal;
    
    public  static  void  main(String[] args){
    mortcalcjp2week3  instanceName  =  new mortcalcjp2week3();
    }