Game Run But Snake Does Not Move / Apples Are Spawned Everywhere
Apr 19, 2014
I tried to make a runnable snake game. When i try to run my code i get this:
Exception in thread "main" java.lang.NullPointerException
at Game.Move(Game.java:85)
at Game.run(Game.java:244)
at Game.main(Game.java:38)
The game runs, but the snake doesn't move, and apples are spawned everywhere.
Here are Move, run and main code:
public static void main(String[] args) {
JFrame frame = new JFrame("Snake");
Game game = new Game();
frame.add(game);
frame.setSize(406, 430);
frame.setVisible(true);
frame.setResizable(false);
gridworld snake game all over the internet, but all of those are the "snakebug extends Bug" version, mine is different. im behind everyone else in apcs so i rarely have any idea what im doing(gridworld especially). our teacher gave us most of the code, which i coped down (hopefully correctly) and he told us that we still needed to fill in the "removeTail" method which i did. basically the snake moves by placing a segment in front then removing the last segment.
When i click run the snakerunner file, i can make the snake segment rotate by pressing the arrow keys, but it doesn't move. when i click the "run" on the gridworld window, the single snake segment just disappears. so the move method is triggering the "removetail" method but it isn't placing the next segment. im starting to think that i copied something wrong from the board, because he showed us the entire move method. i have attached my gridworld files, what is wrong with my snake.java that makes the move method delete a segment but not add one
I am busy programming a clone of the popular phone game they had on Nokia cellphones a long time ago called Snake II but since I know very little about programming I will be using ASCII graphics instead of a 2D graphics engine.
My idea for implementation is having a main class called game which should refresh a grid of ascii characters every, say 0.2 seconds. Then I have another class called Dot. Each Dot object has x and y coordinates, and a direction in the x and y planes (dirx = -1 means left, dirx = 1 means right, diry = 1 means up, diry = -1 means down, and obviously the snake cant move the diagonals)
The Game class prints a "*" symbol where the Dot is, and what I'm trying to do is get the screen to refresh (I think I need to use the sleep() function for this to slow the game down to a reasonable pace), and go in the direction it is supposed to go.
(I haven't programmed this in yet but the snake will be an array of Dot, and at each refresh Dot at position 0 will pass it's coordinates and direction to Dot at position 1, Dot1 to Dot2, Dot2 to Dot3, etc.
Here's my code so far:
A first class called Game.
Java Code: //Not done yet but this is the start to my game of Snake. Basically the class Game generates a Grid of ASCII characters
import java.util.Scanner; public class Game { public static void main(String[] args) { Scanner keyboard = new Scanner(System.in); final int WIDTH = 79;
[Code] .....
My problem now is that I am taking input from the Scanner class. What it does is wait for my input, then it goes on to executing the rest of the code in other words refresh the ASCII grid. This is a problem because I need the snake to keep moving at constant pace while listening to the keyboard.
How can I get my while loop to keep going (i will add a sleep() function later) while listening to the keyboard without stopping?
I'm trying to make a checkers game in Java and I managed to make my grid with it's button on it. Each button which has a pawn on it has it's own actionListener which was all done in the loop as I made the grid as shown in my code below. Now I have a huge problem. I don't know how to handle the move, check if move is legal, jump and double jump. Here is the code I wrote so far. I wrote it in such a way that all the buttons which have a pawn on them can perform the same action but then I'm completely stuck.
import java.awt.event.*; import javax.swing.*; import java.awt.*; public class CheckerBoard extends JPanel{ public static final int WIDTH = 530; public static final int HEIGHT = 530; private JButton[][] grids;
I am having a problem with my java program. My goal is to request the user to enter how many times they want to roll a pair of dices. Each dice have numbers 1-6. When rolling the dices, I randomly pick a number from each dice and total the number. My goal is to calculate the number of times snake-eyes was rolled which is a total of 2 and total number of times a total of 7 was rolled. Here is my code. I am calling the rollDice method to perform the random pick and calculations. The error I am getting is at the bottom of the code.
package dice; import java.util.Scanner; import java.util.Random; public class Dice { public static void main(String[] args) { int numRolls; // number of rolls
[code]...
How many times would you like to roll the two dice? 1000 Exception in thread "main" java.lang.NullPointerException at dice.Dice.main(Dice.java:40) Java Result: 1 BUILD SUCCESSFUL (total time: 4 seconds)
I have a requirement like in a Rich datatable, and i have placed two links up and down in one of the column of each row, here i wanted to swap rows (move up/ down ) the rows when i click the link on a perticular row. is it possible with jsf/ java script?
I am trying to move a JLabel in a JPanel, but can't seem to make it work. I can't provide a compiling code, but a few fragments. I have a JLabel [] array. i want to move with the mouse elements of this array. Let's say i want to move JLabel[i]. I implemented this:
Java Code:
static int labelY; static Point labelX; static Boolean flag = false; jLabel[i].addMouseListener(new MouseAdapter(){ public void mousePressed(MouseEvent evt){ labelY=evt.getY();
[Code]...
I used the bool flag because i can't make changes to the label when it is inside an anonymous class. I also tried using setLocation but that did not work also. I don't get any errors when compiling. But when i run it and try to drag the JLabel[i] i get a long list of errors:
Java Code:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at puzzle.hw$1$2.mouseDragged(hw.java:276) at java.awt.Component.processMouseMotionEvent(Unknown Source) at javax.swing.JComponent.processMouseMotionEvent(Unknown Source) at java.awt.Component.processEvent(Unknown Source) at java.awt.Container.processEvent(Unknown Source)
I am having trouble making my image move to a certain position in a certain amount of time which is set inside a text file. I was wondering what I'm doing wrong and what I'm missing.
import java.io.*; import java.util.*; import java.io.FileReader; public class Animator { EZImage HP;
I noticed it is a huge success to have the backgrounds of games move and the character just move up and down and dodge obstacles.How Do I make a background that scrolls horizontally to the left? I know how to keep the character in place with up and down to move, but not sure how to go about making the background move with obstacles.
I was just trying to figure out why when I hold down a movement key, that my character doesn't move. It only moves if I continuously press the movement key. Here is my code:
package game; import java.awt.*; import TileMap.TileMap; import Handlers.Keys; public class Player { private double x; private double y;
there are two classes here. I need to put the max and min methods should be in the tester class, but I have tried moving it to the tester class and it will not comply. When I run I get a list of errors of "Error:(43, 9) java: illegal start of expression
Error:(43, 16) java: illegal start of expression Error:(43, 22) java: ';' expected Error:(43, 41) java: '.class' expected Error:(43, 52) java: illegal start of expression Error:(43, 51) java: not a statement Error:(43, 53) java: ';' expected Error:(57, 9) java: illegal start of expression Error:(57, 16) java: illegal start of expression Error:(57, 22) java: ';' expected Error:(57, 41) java: '.class' expected Error:(57, 52) java: illegal start of expression Error:(57, 51) java: not a statement Error:(57, 53) java: ';' expected"
package A808; public class FuleTesterV1 { public static void main(String[] args) { String titleLines; titleLines = "Yearly Gas Mi Calc | Assignment 8.08"; String TitleLines; TitleLines = "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~";
I'm having some trouble with figuring out how to move along a doubly linked list for an assignment. The program is supposed to be a simple board game simulation. Here is what I have so far:
Space.java:
public class Space { private String name; public Space next; public Space previous; public Space(String name) { this.name = name;
[Code]...
I seem to have been able to get all the other methods working properly, but I am pretty stuck on how to do the movePlayer. Specifically because it is passing an integer, but my objects are of type Space and Boardgame.
I am just trying to understand during a drag and drop how can I transfer the actual object instead of just creating a new one. I believe I am close but I cannot nail down where I am going wrong. Here is my code I am using to test this.
First/Main:
Java Code:
package main; import javax.swing.SwingUtilities; public class Main { public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable(){
[Code] ......
When I drag the JPanels it just copies and makes a new one. I tested this by having a sysout send to the console a private int that I set during the initial creation of the object.
Below are three classes. The first and second create car objects and the third is the main method. My goal is to move two cars across the window. When I compile and run the program both cars are generated however they will not animate. I am moving them with threads but I cannot seem to find why the cars will not move.
import java.awt.Graphics; import java.awt.Graphics2D; import javax.swing.JComponent; public class CarComponent extends JComponent { private Car car1; private Car car2;
I'm using Dr.Java and doing a numbershifter lab. I have to create a random array of number from 1-10. Then move all of the 7s to the front of the array. The order of the other numbers is not important as long as all numbers follow the group of Lucky 7s. Files needed Numbershifter.java and numbershifterrunner.java. All data is random.I have done the following:
public class NumberShifter { public static int[]makeLucky7Array( int size) { int [] newRay = new int[size]; for( int i=0;i<newRay.length; i++) { newRay[i] = (int)Math.round(Math.random()*10+1);
I have a program which require to navigate a circle with for buttons, Up, Down, Right, and Left. How can i do that?
Here's my code: /* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */
package moveobject; import java.awt.*; import java.applet.*; import java.awt.event.*; public class MoveObject extends Applet implements ActionListener
I'm making a simple game where there's a 10x10 grid and you can move around a selection box and you can move around. I've been trying to make the green selection box to move around but it won't move! I only have right movement in the code but it won't work so far. Here are the classes that have to do greatly with each other.
Opoly works this way: The board is a circular track of variable length (the user determines the length when the game app runs). There is only one player, who begins the game at position 0.
Thus, if the board length is 20, then the board locations start at position 0 and end at position 19. The player starts with a reward of 100, and the goal of the game is to reach or exceed reward value 1000. When this reward value is reached or exceeded, the game is over. When the game ends, your program should report the number of turns the player has taken, and the final reward amount attained.
In Opoly the game piece advances via a spinner - a device that takes on one of the values 1, 2, 3, 4, 5 at random, with each of the five spin values equally likely.
Although the board is circular, you should draw the state of the board as a single "line", using an 'o' to represent the current player position, and * represent all other positions. Thus if the board size is 10, then this board drawing:
**o******
means that the player is at location 2 on the board.
Here are the other Opoly game rules:
If your board piece lands on a board cell that is evenly divisible by 7, your reward doubles.
If you land on the final board cell, you must go back 3 spaces. Thus if the board size is 20, the last position is position 19, and if you land there, you should go back to position 16. (If the position of the last cell is evenly divisible by 7, no extra points are added, but if the new piece location, 3 places back, IS evenly divisible by 7, then extra points ARE added).
If you make it all the way around the board, you get 100 points. Note that if you land exactly on location 0, you first receive 100 extra points (for making it all the around), and then your score is doubled, since 0 is evenly divisible by 7,
Every tenth move (that is, every tenth spin of the spinner, move numbers 10,20,30,... etc.), reduces the reward by 50 points. This penalty is applied up front, as soon as the 10th or 20th or 30th move is made, even if other actions at that instant also apply. Notice that with this rule it's possible for the reward amount to become negative.
Here is the driver class for the game:
import java.util.*; public class OpolyDriver{ public static void main(String[] args){ System.out.println("Enter an int > 3 - the size of the board"); Scanner s = new Scanner(System.in); int boardSize = s.nextInt();
[Code] ....
heres the methods:
REQUIRED CODE STRUCTURE: Your Opoly class must include the following methods (in addition to the Opoly constructor) and must implement the method calls as specified:
playGame - The top-level method that controls the game. No return value, no parameters. Must call drawBoard, displayReport, spinAndMove, isGameOver.
spinAndMove - spins the spinner and then advances the piece according to the rules of the game. No return value, no parameters. Must call spin and move.
spin - generates an integer value from 1 to 5 at random- all equally likely. Returns an integer, no parameters.
move - advances the piece according to the rules of the game. No return value, takes an integer parameter that is a value from 1 to 5.
isGameOver - checks if game termination condition has been met. Returns true if game is over, false otherwise. No parameters.
drawBoard - draws the board using *'s and an o to mark the current board position. Following each board display you should also report the current reward. No return value, no parameters.
displayReport - reports the end of the game, and gives the number of rounds of play, and the final reward. No return value, no parameters.
Im trying to make a tic tac toe game that you play against the computer using a random number generator and two dimensional arrays for the game board. Im not trying to make a GUI, the assignment is to have the board in the console, which I have done. I have run into a few problems with trying to get the computer player to correctly generate 2 integers and have those two integers be a place on the game board. Here is my code so far.
import java.util.Random; import java.util.Scanner; public class TicTacToe { private static Scanner keyboard = new Scanner(System.in); private static char[][] board = new char[3][3]; public static int row, col;
I'm trying to get my animation for my java game to move along the edges of my device. Once it hits the edge I would like it to turn and keep moving along the edges. I'm sure this is easier than I'm making it but I can't find much on this. Right now my animation moves right and goes right off the screen until the app is closed and restarted.
