Exception in thread "AWT-EventQueue-0" at Map.getMap(Map.java:48)

[darkmoon3009]

Maze.java

 
import javax.swing.*;
 
public class Maze
{
	public static void main(String[] args)
  {
	 JFrame mainframe = new JFrame();
	 mainframe.add(new Board());
	 mainframe.setTitle("Noah's Game");
	 mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	 mainframe.setSize(512,512);
	 mainframe.setLocationRelativeTo(null);
	 mainframe.setVisible(true);
 
  }
 
}

Board.java

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.event.*;
import javax.swing.*;
import java.*;
 
public class Board extends JPanel implements ActionListener {
	private Map m;
	private Timer timer;
	private Player p;
	private String Message = "Winner!";
	private boolean Win = false;
	private Font font = new Font("Serif", Font.BOLD,48);
 
	public Board() {
		timer = new Timer(25, this);
		timer.start();
		m = new Map();
		p = new Player();
		addKeyListener(new Al());
		setFocusable(true);
 
	}
 
	public void actionPerformed(ActionEvent e) {
		repaint();
		if(m.getMap(p.getTileX(), p.getTileY()).equals("f"))
		{
			Message = "Winner!";
			Win = true;
		}
	}
 
	public void paint(Graphics g) {
		super.paint(g);
 
		if(!Win){
		for (int y = 0; y < 16; y++) {
			for (int x = 0; x < 16; x++) {
 
				if (m.getMap(x, y).equals("f")) {
					g.drawImage(m.getFinish(), x * 32, y * 32, null);
				}
				if (m.getMap(x, y).equals("g")) {
					g.drawImage(m.getDirt(), x * 32, y * 32, null);
				}
 
				if (m.getMap(x, y).equals("w")) {
					g.drawImage(m.getWall(), x * 32, y * 32, null);
				}
			}
		}
		g.drawImage(p.getPlayer(), p.getTileX() * 32, p.getTileY() * 32, null);
		}
 
		if(Win){
		g.setColor(Color.MAGENTA);
		g.setFont(font);
		g.drawString(Message, 150, 300);
 
		}
 
 
 
	}
 
	public class Al extends KeyAdapter {
		public void keyPresed(KeyEvent e) {
 
			if (e.getKeyCode() == KeyEvent.VK_W) {
				if (!m.getMap(p.getTileX(), p.getTileY() - 1).equals("w"))
					;
				p.move(0, -1);
 
			}
 
			if (e.getKeyCode() == KeyEvent.VK_A) {
				if (!m.getMap(p.getTileX(), p.getTileY() + 1).equals("w"))
					;
				p.move(0, 1);
 
			}
 
			if (e.getKeyCode() == KeyEvent.VK_S) {
				if (!m.getMap(p.getTileX() - 1, p.getTileY()).equals("w"))
					;
				p.move(-1, 0);
 
			}
 
			if (e.getKeyCode() == KeyEvent.VK_D) {
				if (!m.getMap(p.getTileX() + 1, p.getTileY()).equals("w"))
					;
				p.move(1, 0);
 
			}
 
		}
 
		public void keyReleased(KeyEvent e) {
 
		}
 
		public void keyTyped(KeyEvent e) {
 
		}
 
	}
}

Map.java

import java.util.*;
import java.awt.*;
import java.io.*;
 
import javax.swing.ImageIcon;
 
public class Map
{
 
	private Scanner m;
	private String 	Map[] = new String[16];
	private Image dirt ,
	              wall,
	             finish;
 
	public void map()
	{
		ImageIcon img = new ImageIcon("C://Noah's World//dirt.png");
		dirt = img.getImage();
		img = new ImageIcon("C://Noah's World//wall.png");
		wall = img.getImage();
		img = new ImageIcon("C://Noah's World//finish.png");
		finish = img.getImage();
 
 
		openFile();
		readFile();
		closeFile();
 
	}
 
	public Image getFinish()
	{
		return finish;
	}
	public Image getDirt()
	{
		return dirt;
	}
	public Image getWall()
	{
		return wall;
	}
 
 
	public String getMap(int x, int y)
	{
			String index = Map[y].substring(x ,x + 1);
			return index;
	}
 
	public void openFile()
	{
		try{
		m = new Scanner(new File("C://Noah's World//Map.txt"));
		}catch(Exception e)
		{
			System.out.println("error loading map");
		}
	}
 
	public void readFile()
	{
		while(m.hasNext())
		{
			for(int i = 0; i < 14; i++)
			{
				Map[i] = m.next();
			}
		}
	}
 
	public void closeFile()
	{
		m.close();
	}
}

Player.ja

import java.awt.Image;
 
import javax.swing.ImageIcon;
 
public class Player {
	private int tileX, tileY;
	private Image player;
 
	public Player() {
 
		ImageIcon img = new ImageIcon("C://Noah's World//Player.png");
		player = img.getImage();
 
		tileX = 1;
		tileY = 1;
	}
 
	public Image getPlayer() {
		return player;
	}
 
	public int getTileX() {
		return tileX;
	}
 
	public int getTileY() {
		return tileY;
	}
 
	public void move(int dx, int dy) {
 
 
		tileX += dx;
		tileY += dy;
	}
}

Error Report

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at Map.getMap(Map.java:48)
	at Board.actionPerformed(Board.java:28)
	at javax.swing.Timer.fireActionPerformed(Timer.java:312)
	at javax.swing.Timer$DoPostEvent.run(Timer.java:244)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:701)
	at java.awt.EventQueue.access$000(EventQueue.java:102)
	at java.awt.EventQueue$3.run(EventQueue.java:662)
	at java.awt.EventQueue$3.run(EventQueue.java:660)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:671)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at Map.getMap(Map.java:48)
	at Board.paint(Board.java:42)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JLayeredPane.paint(JLayeredPane.java:585)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paintToOffscreen(JComponent.java:5228)
	at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1482)
	at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1413)
	at javax.swing.RepaintManager.paint(RepaintManager.java:1206)
	at javax.swing.JComponent.paint(JComponent.java:1040)
	at java.awt.GraphicsCallback$PaintCallback.run(GraphicsCallback.java:39)
	at sun.awt.SunGraphicsCallback.runOneComponent(SunGraphicsCallback.java:78)
	at sun.awt.SunGraphicsCallback.runComponents(SunGraphicsCallback.java:115)
	at java.awt.Container.paint(Container.java:1967)
	at java.awt.Window.paint(Window.java:3877)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:781)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:728)
	at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:677)
	at javax.swing.RepaintManager.access$700(RepaintManager.java:59)
	at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1621)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:701)
	at java.awt.EventQueue.access$000(EventQueue.java:102)
	at java.awt.EventQueue$3.run(EventQueue.java:662)
	at java.awt.EventQueue$3.run(EventQueue.java:660)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:671)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at Map.getMap(Map.java:48)
	at Board.paint(Board.java:42)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JLayeredPane.paint(JLayeredPane.java:585)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paintToOffscreen(JComponent.java:5228)
	at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1482)
	at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1413)
	at javax.swing.RepaintManager.paint(RepaintManager.java:1206)
	at javax.swing.JComponent.paint(JComponent.java:1040)
	at java.awt.GraphicsCallback$PaintCallback.run(GraphicsCallback.java:39)
	at sun.awt.SunGraphicsCallback.runOneComponent(SunGraphicsCallback.java:78)
	at sun.awt.SunGraphicsCallback.runComponents(SunGraphicsCallback.java:115)
	at java.awt.Container.paint(Container.java:1967)
	at java.awt.Window.paint(Window.java:3877)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:781)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:728)
	at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:677)
	at javax.swing.RepaintManager.access$700(RepaintManager.java:59)
	at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1621)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:701)
	at java.awt.EventQueue.access$000(EventQueue.java:102)
	at java.awt.EventQueue$3.run(EventQueue.java:662)
	at java.awt.EventQueue$3.run(EventQueue.java:660)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:671)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)

[curmudgeon]

Your Map array never gets filled. That's likely because the Map class has no constructor. Give it a valid constructor and this problem may well be fixed.

Remember that constructors have no return type and that Java is case sensitive, in other words map != Map.

Also you should edit your code so that your identifier naming conforms with Java naming standards: class names begin with upper case letters while variable and method names begin with lower case letters. Else your code will be very difficult to read and understand.

[darkmoon3009]

i added this as the constructer

public Map()
	{
		ImageIcon img = new ImageIcon("C://Noah's World//dirt.png");
		dirt = img.getImage();
		img = new ImageIcon("C://Noah's World//wall.png");
		wall = img.getImage();
		img = new ImageIcon("C://Noah's World//finish.png");
		finish = img.getImage();
 
 
		openFile();
		readFile();
		closeFile();
 
	}

but im still gettting errors

Exception in thread "main" java.util.NoSuchElementException
	at java.util.Scanner.throwFor(Scanner.java:907)
	at java.util.Scanner.next(Scanner.java:1416)
	at Map.readFile(Map.java:68)
	at Map.<init>(Map.java:27)
	at Board.<init>(Board.java:19)
	at Maze.main(Maze.java:9)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at Board.actionPerformed(Board.java:28)
	at javax.swing.Timer.fireActionPerformed(Timer.java:312)
	at javax.swing.Timer$DoPostEvent.run(Timer.java:244)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:701)
	at java.awt.EventQueue.access$000(EventQueue.java:102)
	at java.awt.EventQueue$3.run(EventQueue.java:662)
	at java.awt.EventQueue$3.run(EventQueue.java:660)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:671)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:244)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:163)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:147)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:139)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:97)

[Norm]

Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Scanner.java:907)
at java.util.Scanner.next(Scanner.java:1416)
at Map.readFile(Map.java:68)

At line 68 the code calls the Scanner class's next() method. The method throws: NoSuchElementException
Read the API doc for a description of what that means.

Basically you need to test if there is something to be read before trying to read it. The Scanner class has some methods: (names begin with has) that will tell you if there is something available to read so you can skip calling next() when there is no more to read.

[darkmoon3009]

At line 68 the code calls the Scanner class's next() method. The method throws: NoSuchElementException
Read the API doc for a description of what that means.

Basically you need to test if there is something to be read before trying to read it. The Scanner class has some methods: (names begin with has) that will tell you if there is something available to read so you can skip calling next() when there is no more to read.

I don't understand how to put this method into my code. im still a beginner. If you could tell me where it would go into the code and/or what to put. Thanks!

[Norm]

Before calling next() you need to make sure there is data to be read. Call the hasNext method first to determine if there is anything to read. If hasNext() returns false, do not call the next() method.

[darkmoon3009]

Before calling next() you need to make sure there is data to be read. Call the hasNext method first to determine if there is anything to read. If hasNext() returns false, do not call the next() method.

i have added has next so it looks like this :

public void readFile()
	{
		while(m.hasNext())
		{
			for(int i = 0; i < 14; i++)
			{
				Map[i] = m.next();
			}
		}
	}

but i get the same error i think i have not implemented it correctly if you know how to fix this then please help me thx

[Norm]

You must call hasNext() for each time that you call next(). The posted code only calls it once before the inner loop calls it 14 times.

[darkmoon3009]

How do i write that in code??

[Norm]

Some thing like this:

while(input.hasNext() {
  data = input.next();
 // more stuff here
}