I am working on a program to calculate mileage, fuel cost, and travel time when the user selects a vehicle from a combo box. It works well when reading from an array that I put in the program. But now I have to have it read the starting figures from a text file, put it into an array, and then do the calculations. I can get it to read from the file for the first vehicle but I get the Array Index Out Of Bounds Exception:3 on line 181 when I try the other 2 vehicles in the combo box. I have tried many other changes and just can't get it to work. Can anyone help? Here is my code:

import java.io.*;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JComboBox;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.JScrollPane;

public class RoadTripReadFile extends JFrame implements ActionListener {

	//Variables declared to be visible to all methods

	JTextArea output;
	JTextField distanceTf;
	JTextField mpgTf;
	JTextField speedTf;
	JTextField costTf;
	JComboBox carCombo;
	JButton calculateB;
	JButton clearB;

 	String line;
	String[] stats;

	String[] cars = {" ", "GMC", "Toyota", "Chevy"};

	double speed = 32;

	NumberFormat formatter = new DecimalFormat("#0.00");

	public RoadTripReadFile() {
	}

    //This constructor used when RoadTripFrame
    //object is created from main() method and
    //creates the panels and positioning of input/output areas

	private RoadTripReadFile(String title) {

		// uses super class constructor to set title
		super(title);

		//get the container to add the GUI components to

		Container window = getContentPane();

		JPanel northPanel = new JPanel();

		//Panel layout will be a gridlayout
		GridLayout northGrid = new GridLayout(6,2);

		northPanel.setLayout(northGrid);

		window.add(northPanel, BorderLayout.NORTH);

		//create labels, JComboBox, input fields

		JLabel titleL = new JLabel("Road Trip Calculator");

		JLabel carLabel = new JLabel("Select Car:");

		carCombo = new JComboBox(cars);
		carCombo.setSelectedIndex(0);
		carCombo.addActionListener(this);

		northPanel.add(carLabel);
		northPanel.add(carCombo);

		JLabel distanceL = new JLabel("Distance:");
		distanceTf = new JTextField(10);

		JLabel mpgL = new JLabel("MPG:");
		mpgTf = new JTextField(10);

		JLabel speedL = new JLabel("Speed:");
		speedTf = new JTextField(10);

		JLabel costpergallonL = new JLabel("Cost:");
		costTf = new JTextField(10);

		// add components to the panel

		northPanel.add(distanceL);
		northPanel.add(distanceTf);
		northPanel.add(mpgL);
		northPanel.add(mpgTf);
		northPanel.add(speedL);
		northPanel.add(speedTf);
		northPanel.add(costpergallonL);
		northPanel.add(costTf);

		//create buttons

		calculateB = new JButton("Calculate");
		calculateB.addActionListener(this);
		clearB = new JButton("Clear");
		clearB.addActionListener(this);

		//add buttons to panel

		northPanel.add(calculateB);
		northPanel.add(clearB);

		// create the text area for the output
		// and make it a scrolling pane

		output = new JTextArea(200,200);

		JScrollPane scrollPane = new JScrollPane(output);

		//add the output and ScrollPane to the Center areas

		window.add(scrollPane, BorderLayout.CENTER);

	}
       //reads from a text file for car data
	public void readFromFile(String readFromFileName) throws IOException {

		File carFile = new File(readFromFileName);

		FileReader reader = new FileReader(carFile);
		BufferedReader buffReader = new BufferedReader(reader);
		String vehicleData = buffReader.readLine();

		stats = vehicleData.split(" ");

		for (int i = 0; i<stats.length; i++){
			
		}
	}

	//This method is called when the buttons are pressed

	public void actionPerformed(ActionEvent event) {
		boolean errorOccured = false;

		Object source = event.getSource();

		//if the JComboBox item is selected,
		//populate the text fields with the correct data

		if (source instanceof JComboBox){
			//clear the text area
			output.setText(null);

			if (carCombo.getSelectedItem().equals("GMC")){
				distanceTf.setText(stats[0]);
				mpgTf.setText(stats[1]);
				speedTf.setText("32");
				costTf.setText(stats[2]);
			}
			else if (carCombo.getSelectedItem().equals("Toyota")){
				distanceTf.setText(stats[3]);
				mpgTf.setText(stats[4]);
				speedTf.setText("32");
				costTf.setText(stats[5]);
			}
			else if (carCombo.getSelectedItem().equals("Chevy")){
				distanceTf.setText(stats[6]);
				mpgTf.setText(stats[7]);
				speedTf.setText("32");
				costTf.setText(stats[8]);
			}
		}

		//if the Calculate button is clicked,get text and parse it,
		//if an error is made, let user know to correct it,
		//then calculate the trip data and print the output,
		//output and calculations will be based on increments of 10,
		//else if Clear is clicked, clear the text fields;

		else if (source instanceof JButton){

			if (source == calculateB) {

			String distanceEntered = distanceTf.getText();

			double distance = 0;
			try {
				distance = Double.parseDouble(distanceEntered);
			} catch (NumberFormatException e) {
				JOptionPane.showMessageDialog(this,
					"Please enter valid number for distance.",
					"Error",JOptionPane.ERROR_MESSAGE);
				errorOccured = true;
			}

			String mpgEntered = mpgTf.getText();

			double mpg = 0;
			try {
				mpg = Double.parseDouble(mpgEntered);
			}catch (NumberFormatException e) {
				JOptionPane.showMessageDialog(this,
					"Please enter valid number for miles per gallon.",
					"Error",JOptionPane.ERROR_MESSAGE);
				errorOccured = true;
			}

			String speedEntered = speedTf.getText();

			double speed = 0;
			try {
				speed = Double.parseDouble(speedEntered);
			}catch (NumberFormatException e) {
				JOptionPane.showMessageDialog(this,
					"Please enter valid number for speed.",
					"Error",JOptionPane.ERROR_MESSAGE);
				errorOccured = true;
			}

			String costEntered = costTf.getText();

			double cost = 0;
			try {
				cost = Double.parseDouble(costEntered);
			}catch (NumberFormatException e) {
				JOptionPane.showMessageDialog(this,
					"Please enter valid number for fuel cost per gallon.",
					"Error",JOptionPane.ERROR_MESSAGE);
				errorOccured = true;
			}
			if (errorOccured == true)
				return;

			double miles;
			output.setText("Distance\tGallons Used\tFuel Cost\tHours and Seconds\n\n");

			for (miles = 10; miles <= distance; miles = miles + 10){

			double gallonsUsed = miles / mpg;
			double fuelCost = gallonsUsed * cost;
			double travel = miles / speed;
			double hours = travel;
			double decimalValue = miles % speed;
			double seconds = (decimalValue / speed) * 3600;

			output.append(miles + "\t");
			output.append(formatter.format(gallonsUsed) + "gallons\t");
			output.append("$" + formatter.format(fuelCost) + "\t");
			output.append(hours + " hours, and " + seconds + " seconds\n");
			}
			output.setCaretPosition(0);
		 }

		else if (source instanceof JButton){
				if (source == clearB) {

				distanceTf.setText("");
				mpgTf.setText("");
				speedTf.setText("");
				costTf.setText("");
				output.setText("");
			}
		 }
	 }
}


	//Entry point (main method) for the program

	public static void main(String []args){

		//create the RoadTripReadFile object, set the size, and make it visible

		RoadTripReadFile frame = new RoadTripReadFile("Road Trip Calculator");
		try {
				frame.readFromFile("vehicle.txt");
		} catch (IOException e){
				e.printStackTrace();
		}


		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.pack();
		frame.setSize(500, 500);
		frame.setVisible(true);
	}

}

Thanks.

I can get it to read from the file for the first vehicle but I get the Array Index Out Of Bounds Exception:3 on line 181 .

well, I wasn't planning on counting all those lines :-/ you may want to use code tags, in such a way that the line-number is printed next to the line, makes it easier to read too.

//yourCodeHere

without the 's

>
> //yourCodeHere
>

Use the [noparse][/noparse] tag for writing out tags without interpreting them. E.g.:
[noparse][code=java]code-here [/code][/noparse]

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