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Memory game not revealing correct guesses

This program is a Domino memory game where you flip dominos until you make a correct guess where the correct dominos are supposed to stay revealed. However the problem is that while the game does work correctly the dominos do not stay revealed nor does the game end.
This is the code for my Domino Class
`
public class Domino {
private int top, bottom;
private boolean revealed;
public Domino(int x, int y) {
if (x > y) {
top = y;
bottom = x;
} else {
top = x;
bottom = y;
}
}
public int getTop() {
return top;
}
public int getBottom() {
return bottom;
}
public boolean isRevealed() {
if (revealed)
return true;
return false;
}
public void setRevealed(boolean revealed) {
this.revealed = revealed;
}
public boolean equals(Domino other) {
if (top == bottom)
return true;
return false;
}
}
`
Then here is the memory game class (called MemoryLane)
`
import java.util.Arrays;
import java.util.Random;
public class MemoryLane
{
private Domino[] board;
public MemoryLane(int max)
{
board = new Domino[(max * max) + max];
int i = 0;
for(int top = 1; top <= max; top++)
for(int bot = 1; bot <= max; bot++)
{
// make new Domino(2x) +
// save into array
if(top <= bot)
{
board[i] = new Domino(top, bot);
i++;
board[i] = new Domino(top, bot);
i++;
}
}
shuffle();
}
private void shuffle()
{
int index;
Random random = new Random();
for (int i = board.length - 1; i > 0; i--)
{
index = random.nextInt(i + 1);
if (index != i)
{
Domino temp = board[index];
board[index] = board[i];
board[i] = temp;
}
}
}
public boolean guess(int i, int k)
{
if(board[i] == board[k])
{
return true;
}
return false;
}
public String peek(int a, int b)
{
String text = new String();
text += ("[" + board[a].getTop()+ "] [" + board[b].getTop()+ "]\n");
text += ("[" + board[a].getBottom()+ "] [" + board[b].getBottom()+ "]\n");
return text;
}
public boolean gameOver() {
int count = 0;
for(int i=0; i< board.length; i++)
{
if(board[i].isRevealed())
count ++;
}
return (count == board.length);
}
public String toString() {
String text = new String();
for(int i=0; i< board.length; i++)
{
if(board[i].isRevealed())
text += ("[" + board[i].getTop()+ "] ");
else
text += ("[ ] ");
}
text += ('\n');
for(int i=0; i< board.length; i++)
{
if(board[i].isRevealed())
text += ("[" + board[i].getBottom()+ "] ");
else
text += ("[ ] ");
}
return text;
}
}
`
Then here is the driver (the driver was provided to me by a third party so it must work as it is presented and cannot be changed)
`
import java.util.Scanner;
public class MemoryLaneDriver
{
public static void main(String[] args)
{
String message = "Welcome to Memory Lane!" + "\n" +
"Choose two indexes to reveal the corresponding dominoes." + "\n" +
"If the dominoes match, they stay revealed." + "\n" +
"Reveal all the dominoes to win the game!" + "\n";
System.out.println(message);
Scanner input = new Scanner(System.in);
MemoryLane game = new MemoryLane(2);
long start = System.currentTimeMillis();
while(!game.gameOver())
{
System.out.println(game);
System.out.print("First: ");
int first = input.nextInt();
System.out.print("Second: ");
int second = input.nextInt();
game.guess(first, second);
System.out.println(game.peek(first, second) + "\n");
}
long stop = System.currentTimeMillis();
long elapsed = (stop - start) / 1000;
System.out.println(game);
System.out.println("\nYou win!");
System.out.println("Total time: " + elapsed + "s");
}
}
`
I have tried using the methods in Domino like setRevealed and isRevealed in the guess method (for example when i try board.setRevealed = true or board.isRevealed = true), but it wont work and turns up red in IntelliJ. I can also not use any Stringbuilder uses (such as append) because it is outside of what has been covered in class.
When I say the game is working correctly, I mean that it outputs my choices like:
`
Welcome to Memory Lane!
Choose two indexes to reveal the corresponding dominoes.
If the dominoes match, they stay revealed.
Reveal all the dominoes to win the game!
[ ] [ ] [ ] [ ] [ ] [ ]
[ ] [ ] [ ] [ ] [ ] [ ]
First: 1
Second: 3
[2] [2]
[2] [2]
[ ] [ ] [ ] [ ] [ ] [ ]
[ ] [ ] [ ] [ ] [ ] [ ]
First:
`
However as you can see it is not revealing the correct guess, and even if I guess all of the Dominos correctly the game does not end.

So, in your original code, you were using board[i] == board[k] which is comparing memory address locations and not the object properties, instead, you should be using board[i].equals(board[k]).
In this case you need to override equals method of the Domino class in order to change how the comparison works, for example...
#Override
public int hashCode() {
int hash = 7;
hash = 59 * hash + this.getTop();
hash = 59 * hash + this.getBottom();
return hash;
}
#Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (!(obj instanceof Domino)) {
return false;
}
final Domino other = (Domino) obj;
if (this.getTop() != other.getTop()) {
return false;
}
if (this.getBottom() != other.getBottom()) {
return false;
}
return true;
}
It's important to remember, if you override equals you should also override hashCode as they have an important relationship to each other.
You also never call setRevealed, which I guess should be done in guess
public boolean guess(int i, int k) {
if (board[i].equals(board[k])) {
board[i].setRevealed(true);
board[k].setRevealed(true);
return true;
}
return false;
}
Runnable example...
import java.util.Random;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
new Main();
}
Main() {
String message = "Welcome to Memory Lane!" + "\n"
+ "Choose two indexes to reveal the corresponding dominoes." + "\n"
+ "If the dominoes match, they stay revealed." + "\n"
+ "Reveal all the dominoes to win the game!" + "\n";
System.out.println(message);
Scanner input = new Scanner(System.in);
MemoryLane game = new MemoryLane(2);
long start = System.currentTimeMillis();
while (!game.gameOver()) {
// This is just making it easier to cheat.
System.out.println(game.debug());
System.out.println(game);
System.out.print("First: ");
int first = input.nextInt();
System.out.print("Second: ");
int second = input.nextInt();
game.guess(first, second);
System.out.println(game.peek(first, second) + "\n");
}
long stop = System.currentTimeMillis();
long elapsed = (stop - start) / 1000;
System.out.println(game);
System.out.println("\nYou win!");
System.out.println("Total time: " + elapsed + "s");
}
public class Domino {
private int top, bottom;
private boolean revealed;
public Domino(int x, int y) {
if (x > y) {
top = y;
bottom = x;
} else {
top = x;
bottom = y;
}
}
public int getTop() {
return top;
}
public int getBottom() {
return bottom;
}
public boolean isRevealed() {
return revealed;
}
public void setRevealed(boolean revealed) {
this.revealed = revealed;
}
#Override
public int hashCode() {
int hash = 7;
hash = 59 * hash + this.getTop();
hash = 59 * hash + this.getBottom();
return hash;
}
#Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (!(obj instanceof Domino)) {
return false;
}
final Domino other = (Domino) obj;
if (this.getTop() != other.getTop()) {
return false;
}
if (this.getBottom() != other.getBottom()) {
return false;
}
return true;
}
}
public class MemoryLane {
private Domino[] board;
public MemoryLane(int max) {
board = new Domino[(max * max) + max];
int i = 0;
for (int top = 1; top <= max; top++) {
for (int bot = 1; bot <= max; bot++) {
// make new Domino(2x) +
// save into array
if (top <= bot) {
board[i] = new Domino(top, bot);
i++;
board[i] = new Domino(top, bot);
i++;
}
}
}
shuffle();
}
private void shuffle() {
int index;
Random random = new Random();
for (int i = board.length - 1; i > 0; i--) {
index = random.nextInt(i + 1);
if (index != i) {
Domino temp = board[index];
board[index] = board[i];
board[i] = temp;
}
}
}
public boolean guess(int i, int k) {
if (board[i].equals(board[k])) {
board[i].setRevealed(true);
board[k].setRevealed(true);
return true;
}
return false;
}
public String peek(int a, int b) {
String text = new String();
text += ("[" + board[a].getTop() + "] [" + board[b].getTop() + "]\n");
text += ("[" + board[a].getBottom() + "] [" + board[b].getBottom() + "]\n");
return text;
}
public boolean gameOver() {
int count = 0;
for (int i = 0; i < board.length; i++) {
if (board[i].isRevealed()) {
count++;
}
}
return (count == board.length);
}
public String debug() {
String text = new String();
for (int i = 0; i < board.length; i++) {
text += ("[" + board[i].getTop() + "] ");
}
text += ('\n');
for (int i = 0; i < board.length; i++) {
text += ("[" + board[i].getBottom() + "] ");
}
return text;
}
public String toString() {
String text = new String();
for (int i = 0; i < board.length; i++) {
if (board[i].isRevealed()) {
text += ("[" + board[i].getTop() + "] ");
} else {
text += ("[ ] ");
}
}
text += ('\n');
for (int i = 0; i < board.length; i++) {
if (board[i].isRevealed()) {
text += ("[" + board[i].getBottom() + "] ");
} else {
text += ("[ ] ");
}
}
return text;
}
}
}

I figured it out
The problem was my equals method was comparing top to bottom which is why i was getting such weird results. I changed it to
public boolean equals(Domino other){
return this.top == other.top && this.bottom == other.bottom
}
and now it works perfectly fine thanks for all of the help guys!

Java help! implementing a 2d array of a certain object, the object has multiple private data types and objects

I'm trying to make a 2d array of an object in java. This object in java has several private variables and methods in it, but won't work. Can someone tell me why and is there a way I can fix this?
This is the exeception I keep getting for each line of code where I try to initialize and iterate through my 2d object.
"Exception in thread "main" java.lang.NullPointerException
at wumpusworld.WumpusWorldGame.main(WumpusWorldGame.java:50)
Java Result: 1"
Here is my main class:
public class WumpusWorldGame {
class Agent {
private boolean safe;
private boolean stench;
private boolean breeze;
public Agent() {
safe = false;
stench = false;
breeze = false;
}
}
/**
* #param args
* the command line arguments
* #throws java.lang.Exception
*/
public static void main(String [] args) {
// WumpusFrame blah =new WumpusFrame();
// blah.setVisible(true);
Scanner input = new Scanner(System.in);
int agentpts = 0;
System.out.println("Welcome to Wumpus World!\n ******************************************** \n");
//ArrayList<ArrayList<WumpusWorld>> woah = new ArrayList<ArrayList<WumpusWorld>>();
for (int i = 0 ; i < 5 ; i++) {
WumpusWorldObject [] [] woah = new WumpusWorldObject [5] [5];
System.out.println( "*********************************\n Please enter the exact coordinates of the wumpus (r and c).");
int wumpusR = input.nextInt();
int wumpusC = input.nextInt();
woah[wumpusR][wumpusC].setPoints(-3000);
woah[wumpusR][wumpusC].setWumpus();
if ((wumpusR <= 5 || wumpusC <= 5) && (wumpusR >= 0 || wumpusC >= 0)) {
woah[wumpusR][wumpusC].setStench();
}
if (wumpusC != 0) {
woah[wumpusR][wumpusC - 1].getStench();
}
if (wumpusR != 0) {
woah[wumpusR - 1][wumpusC].setStench();
}
if (wumpusC != 4) {
woah[wumpusR][wumpusC + 1].setStench();
}
if (wumpusR != 4) {
woah[wumpusR + 1][wumpusC].setStench();
}
System.out.println( "**************************************\n Please enter the exact coordinates of the Gold(r and c).");
int goldR = input.nextInt();
int goldC = input.nextInt();
woah[goldR][goldC].setGold();
System.out.println("***************************************\n How many pits would you like in your wumpus world?");
int numPits = input.nextInt();
for (int k = 0 ; k < numPits ; k++) {
System.out.println("Enter the row location of the pit");
int r = input.nextInt();
System.out.println("Enter the column location of the pit");
int c = input.nextInt();
woah[r][c].setPit();
if ((r <= 4 || c <= 4) && (r >= 0 || c >= 0)) {
woah[r][c].setBreeze();
}
if (c != 0) {
woah[r][c - 1].setBreeze();
}
if (r != 0) {
woah[r - 1][c].setBreeze();
}
if (c != 4) {
woah[r][c + 1].setBreeze();
}
if (r != 4) {
woah[r + 1][c].setBreeze();
}
}
for (int x = 0 ; x < 4 ; x++) {
int j = 0;
while (j < 4) {
agentpts = agentpts + woah[x][j].getPoints();
Agent [] [] k = new Agent [4] [4];
if (woah[x][j].getWumpus() == true) {
agentpts = agentpts + woah[x][j].getPoints();
System.out.println("You just got ate by the wumpus!!! THE HORROR!! Your score is " + agentpts);
}
if (woah[x][j].getStench() == true) {
k[x][j].stench = true;
System.out.println("You smell something funny... smells like old person.");
}
if (woah[x][j].getBreeze() == true) {
k[x][j].breeze = true;
System.out.println("You hear a breeze. yeah");
}
if (woah[x][j].getPit() == true) {
agentpts = agentpts + woah[x][j].getPoints();
System.out.println("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH! you dumb bith, your dead now.");
}
// if breeze or stench, if breeze and stench, if nothing, etc then move.
k[x][j].safe = true;
// if(k[i][j].isSafe()!=true){
// } else { }
}
}
}
}
}
Here is my class object that I'm trying to implement:
package wumpusworld;
/**
*
* #author Jacob
*/
public class WumpusWorldObject {
private boolean stench;
private boolean breeze;
private boolean pit;
private boolean wumpus;
private boolean gold;
private int points;
private boolean safe;
public WumpusWorldObject(){
}
public boolean getPit() {
return pit;
}
public void setPit() {
this.pit = true;
}
public boolean getWumpus() {
return wumpus;
}
public void setWumpus() {
this.wumpus = true;
}
public int getPoints() {
return points;
}
public void setPoints(int points) {
this.points = points;
}
public boolean getStench() {
return stench;
}
public void setStench() {
this.stench = true;
}
public boolean getBreeze() {
return breeze;
}
public void setBreeze() {
this.breeze = true;
}
public boolean getSafe() {
return safe;
}
public void setSafe() {
this.safe = true;
}
public void setGold(){
this.gold=true;
}
}

Creating array doesn't mean it will be automatically filled with new instances of your class. There are many reasons for that, like
which constructor should be used
what data should be passed to this constructor.
This kind of decisions shouldn't be made by compiler, but by programmer, so you need to invoke constructor explicitly.
After creating array iterate over it and fill it with new instances of your class.
for (int i=0; i<yourArray.length; i++)
for (int j=0; j<yourArray[i].length; j++)
yourArray[i][j] = new ...//here you should use constructor

AClass[][] obj = new AClass[50][50];
is not enough, you have to create instances of them like
obj[i][j] = new AClass(...);
In your code the line
woah[wumpusR][wumpusC].setPoints(-3000);
must be after
woah[wumpusR][wumpusC] = new WumpusWorldObject();
.

How to freely traverse the elements in a two-dimensional array by cardinal direction? (DOWN, UP, LEFT, RIGHT)

This question is about figuring the path through a maze, as is represented by a two-dimensional array. For example, the path through this maze
0 1 2 3 4
---------
0| 1 0 1 1 1
1| 1 0 0 0 1
2| 1 0 1 0 1
3| 1 1 1 0 1
4| 1 1 1 0 1
is
START: [0,1]
Down: [1,1]
Right: [1,2]
Right: [1,3]
Down: [2,3]
Down: [3,3]
Down: [4,3]
The poster was attempting to do this purely with recursion, and actually posted four different questions about it within five hours--which speaks to its complexity.
This got me thinking of the more generic question: How do you freely move around the elements in a two-dimensional array, in any cardinal direction? DOWN, UP, LEFT, RIGHT
If this problem can be solved, then traversing a maze would be much easier.

I solved this with two classes, and an Enum.
First, the enum, which defines the direction you want to move and determines the new indexes, one-at-a-time, based on its movement.
enum Direction {
UP(-1, 0),
DOWN(1, 0),
LEFT(0, -1),
RIGHT(0, 1);
private final int rowSteps;
private final int colSteps;
private Direction(int rowSteps, int colSteps) {
this.rowSteps = rowSteps;
this.colSteps = colSteps;
}
public int getNewRowIdx(int currentRowIdx) {
return (currentRowIdx + getRowSteps());
}
public int getNewColIdx(int currentColIdx) {
return (currentColIdx + getColSteps());
}
public int getRowSteps() {
return rowSteps;
}
public int getColSteps() {
return colSteps;
}
};
The main class is called GridPosition (below). First you set the double-array grid into it, via its int[][] constructor, and store that instance statically:
private static final GridPosition GRID_HOLDER = new GridPosition(GRID);
(This step could be designed better, but it works. Also, it should accept any type.)
After setting the grid (which is a one-time-only thing, per-execution), then the x/y constructor is used to declare an initial position:
GridPosition pos = new GridPosition(0, 0);
And after that, just move as necessary:
pos = pos.getNeighbor(Direction.RIGHT);
pos = pos.getNeighbor(Direction.RIGHT);
pos = pos.getNeighbor(Direction.DOWN);
...
The value of each position is retrieved by pos.getValue(). (As an aside: The huge 2d-array used for the maze--at the bottom of this post, in the "full code"--should really contain one-bit booleans, instead of 4-byte ints, but looking at the array's code makes sense with ints, and doesn't with booleans... Note that it should at least be changed to bytes.)
So regarding movement, if you attempt to get a neighbor when there is none, such as moving left at the left edge, an IllegalStateException is thrown. Use the is*Edge() functions to avoid this.
The GridPosition class also has a convenient debugging function called getNineByNine(), which returns a 9x9 grid of the array values (as a string), where the middle item is the current position.
import java.util.Arrays;
import java.util.Objects;
class GridPosition {
//state
private static int[][] GRID;
private final int rowIdx;
private final int colIdx;
//internal
private final int rowIdxMinus1;
private final int colIdxMinus1;
public GridPosition(int[][] GRID) {
if(this.GRID != null) {
throw new IllegalStateException("Grid already set. Use x/y constructor.");
}
GridPosition.GRID = GRID;
//TODO: Crash if null or empty, or sub-arrays null or empty, or unequal lengths, or contain anything but 0 or -1.
rowIdx = -1;
colIdx = -1;
rowIdxMinus1 = -1;
colIdxMinus1 = -1;
}
public GridPosition(int rowIdx, int colIdx) {
if(GridPosition.GRID == null) {
throw new IllegalStateException("Must set grid with: new GridPosition(int[][]).");
}
if(rowIdx < 0 || rowIdx >= GridPosition.getRowCount()) {
throw new IllegalArgumentException("rowIdx (" + rowIdx + ") is invalid.");
}
if(colIdx < 0 || colIdx >= GridPosition.getColumnCount()) {
throw new IllegalArgumentException("colIdx (" + colIdx + ") is invalid.");
}
this.rowIdx = rowIdx;
this.colIdx = colIdx;
rowIdxMinus1 = (rowIdx - 1);
colIdxMinus1 = (colIdx - 1);
}
public int getValue() {
return GridPosition.GRID[getRowIdx()][getColumnIdx()];
}
public int getRowIdx() {
return rowIdx;
}
public int getColumnIdx() {
return colIdx;
}
public GridPosition getNeighbor(Direction dir) {
Objects.requireNonNull(dir, "dir");
return (new GridPosition(
dir.getNewRowIdx(getRowIdx()),
dir.getNewColIdx(getColumnIdx())));
}
public GridPosition getNeighborNullIfEdge(Direction dir) {
if(isEdgeForDirection(dir)) {
return null;
}
return getNeighbor(dir);
}
public int getNeighborValueNeg1IfEdge(Direction dir) {
GridPosition pos = getNeighborNullIfEdge(dir);
return ((pos == null) ? -1 : pos.getValue());
}
public static final int getRowCount() {
return GRID.length;
}
public static final int getColumnCount() {
return GRID[0].length;
}
public boolean isEdgeForDirection(Direction dir) {
Objects.requireNonNull(dir);
switch(dir) {
case UP: return isTopEdge();
case DOWN: return isBottomEdge();
case LEFT: return isLeftEdge();
case RIGHT: return isRightEdge();
}
throw new IllegalStateException(toString() + ", dir=" + dir);
}
public boolean isLeftEdge() {
return (getColumnIdx() == 0);
}
public boolean isTopEdge() {
return (getRowIdx() == 0);
}
public boolean isBottomEdge() {
return (getRowIdx() == rowIdxMinus1);
}
public boolean isRightEdge() {
return (getColumnIdx() == colIdxMinus1);
}
public String toString() {
return "[" + getRowIdx() + "," + getColumnIdx() + "]=" + getValue();
}
public String getNineByNine() {
int[][] nineByNine = new int[3][3];
//Middle row
nineByNine[1][1] = getValue();
nineByNine[1][0] = getNeighborValueNeg1IfEdge(Direction.LEFT);
nineByNine[1][2] = getNeighborValueNeg1IfEdge(Direction.RIGHT);
//Top
GridPosition posUp = getNeighborNullIfEdge(Direction.UP);
if(posUp != null) {
nineByNine[0][0] = posUp.getNeighborValueNeg1IfEdge(Direction.LEFT);
nineByNine[0][1] = posUp.getValue();
nineByNine[0][2] = posUp.getNeighborValueNeg1IfEdge(Direction.RIGHT);
}
//Bottom
GridPosition posDown = getNeighborNullIfEdge(Direction.DOWN);
if(posDown != null) {
nineByNine[2][0] = posDown.getNeighborValueNeg1IfEdge(Direction.LEFT);
nineByNine[2][1] = posDown.getValue();
nineByNine[2][2] = posDown.getNeighborValueNeg1IfEdge(Direction.RIGHT);
}
String sLS = System.getProperty("line.separator", "\r\n");
return "Middle position in 9x9 grid is *this*: " + toString() + sLS +
Arrays.toString(nineByNine[0]) + sLS +
Arrays.toString(nineByNine[1]) + sLS +
Arrays.toString(nineByNine[2]);
}
}
Here's a demo usage:
public class GridPosDemo {
private static final int[][] GRID = new int[][] {
//mega grid goes here...
};
private static final GridPosition GRID_HOLDER = new GridPosition(GRID);
public static final void main(String[] ignored) {
GridPosition pos = new GridPosition(0, 0);
System.out.println("start: " + pos);
pos = pos.getNeighbor(Direction.RIGHT);
System.out.println("right: " + pos);
pos = pos.getNeighbor(Direction.RIGHT);
System.out.println("right: " + pos);
pos = pos.getNeighbor(Direction.DOWN);
System.out.println("down: " + pos);
pos = pos.getNeighbor(Direction.DOWN);
System.out.println("down: " + pos);
pos = pos.getNeighbor(Direction.RIGHT);
System.out.println("right: " + pos);
pos = pos.getNeighbor(Direction.DOWN);
System.out.println("down: " + pos);
pos = pos.getNeighbor(Direction.LEFT);
System.out.println("left: " + pos);
pos = pos.getNeighbor(Direction.UP);
System.out.println("up: " + pos);
pos = pos.getNeighbor(Direction.UP);
System.out.println("up: " + pos);
System.out.println(pos.getNineByNine());
}
}
Output
[C:\java_code\]java GridPosDemo
start: [0,0]=1
right: [0,1]=1
right: [0,2]=1
down: [1,2]=1
down: [2,2]=1
right: [2,3]=1
down: [3,3]=0
left: [3,2]=1
up: [2,2]=1
up: [1,2]=1
Middle position in 9x9 grid is *this*: [1,2]=1
[1, 1, 1]
[0, 1, 0]
[0, 1, 1]
In order to use this for traversing the correct path through a maze, this needs "collision detection" added to it (so it doesn't go through walls), in addition to something to keep track of where you've been (so you don't end up back at the start-position). Such as with some getNeighborIfNotWall(Direction) and isWallToLeft() functions.
Putting aside the maze-question, I would do the following before considering these classes complete:
Make the array-type generic, instead of ints
Add error checking, as documented in the code
Re-design how you set the grid.
Add diagonal directions: UP_LEFT, UP_RIGHT, DOWN_LEFT, DOWN_RIGHT
Add the ability to move multiple steps in one direction: getNeighbor(3, Direction.DOWN)
Here's the entire source-code file, containing all of the above (including the mega-maze grid):
//Needed only by GridPosition
import java.util.Arrays;
import java.util.Objects;
enum Direction {
UP(-1, 0),
DOWN(1, 0),
LEFT(0, -1),
RIGHT(0, 1);
//config
private final int rowSteps;
private final int colSteps;
private Direction(int rowSteps, int colSteps) {
this.rowSteps = rowSteps;
this.colSteps = colSteps;
}
public int getNewRowIdx(int currentRowIdx) {
return (currentRowIdx + getRowSteps());
}
public int getNewColIdx(int currentColIdx) {
return (currentColIdx + getColSteps());
}
public int getRowSteps() {
return rowSteps;
}
public int getColSteps() {
return colSteps;
}
};
class GridPosition {
//config
private static int[][] GRID;
private final int rowIdx;
private final int colIdx;
//internal
private final int rowIdxMinus1;
private final int colIdxMinus1;
public GridPosition(int[][] GRID) {
if(this.GRID != null) {
throw new IllegalStateException("Grid already set. Use x/y constructor.");
}
GridPosition.GRID = GRID;
//TODO: Crash if null or empty, or sub-arrays null or empty, or unequal lengths, or contain anything but 0 or -1.
rowIdx = -1;
colIdx = -1;
rowIdxMinus1 = -1;
colIdxMinus1 = -1;
}
public GridPosition(int rowIdx, int colIdx) {
if(GridPosition.GRID == null) {
throw new IllegalStateException("Must set grid with: new GridPosition(int[][]).");
}
if(rowIdx < 0 || rowIdx >= GridPosition.getRowCount()) {
throw new IllegalArgumentException("rowIdx (" + rowIdx + ") is invalid.");
}
if(colIdx < 0 || colIdx >= GridPosition.getColumnCount()) {
throw new IllegalArgumentException("colIdx (" + colIdx + ") is invalid.");
}
this.rowIdx = rowIdx;
this.colIdx = colIdx;
rowIdxMinus1 = (rowIdx - 1);
colIdxMinus1 = (colIdx - 1);
}
public int getValue() {
return GridPosition.GRID[getRowIdx()][getColumnIdx()];
}
public int getRowIdx() {
return rowIdx;
}
public int getColumnIdx() {
return colIdx;
}
public GridPosition getNeighbor(Direction dir) {
Objects.requireNonNull(dir, "dir");
return (new GridPosition(
dir.getNewRowIdx(getRowIdx()),
dir.getNewColIdx(getColumnIdx())));
}
public GridPosition getNeighborNullIfEdge(Direction dir) {
if(isEdgeForDirection(dir)) {
return null;
}
return getNeighbor(dir);
}
public int getNeighborValueNeg1IfEdge(Direction dir) {
GridPosition pos = getNeighborNullIfEdge(dir);
return ((pos == null) ? -1 : pos.getValue());
}
public static final int getRowCount() {
return GRID.length;
}
public static final int getColumnCount() {
return GRID[0].length;
}
public boolean isEdgeForDirection(Direction dir) {
Objects.requireNonNull(dir);
switch(dir) {
case UP: return isTopEdge();
case DOWN: return isBottomEdge();
case LEFT: return isLeftEdge();
case RIGHT: return isRightEdge();
}
throw new IllegalStateException(toString() + ", dir=" + dir);
}
public boolean isLeftEdge() {
return (getColumnIdx() == 0);
}
public boolean isTopEdge() {
return (getRowIdx() == 0);
}
public boolean isBottomEdge() {
return (getRowIdx() == rowIdxMinus1);
}
public boolean isRightEdge() {
return (getColumnIdx() == colIdxMinus1);
}
public String toString() {
return "[" + getRowIdx() + "," + getColumnIdx() + "]=" + getValue();
}
public String getNineByNine() {
int[][] nineByNine = new int[3][3];
//Middle row
nineByNine[1][1] = getValue();
nineByNine[1][0] = getNeighborValueNeg1IfEdge(Direction.LEFT);
nineByNine[1][2] = getNeighborValueNeg1IfEdge(Direction.RIGHT);
//Top
GridPosition posUp = getNeighborNullIfEdge(Direction.UP);
if(posUp != null) {
nineByNine[0][0] = posUp.getNeighborValueNeg1IfEdge(Direction.LEFT);
nineByNine[0][1] = posUp.getValue();
nineByNine[0][2] = posUp.getNeighborValueNeg1IfEdge(Direction.RIGHT);
}
//Bottom
GridPosition posDown = getNeighborNullIfEdge(Direction.DOWN);
if(posDown != null) {
nineByNine[2][0] = posDown.getNeighborValueNeg1IfEdge(Direction.LEFT);
nineByNine[2][1] = posDown.getValue();
nineByNine[2][2] = posDown.getNeighborValueNeg1IfEdge(Direction.RIGHT);
}
String sLS = System.getProperty("line.separator", "\r\n");
return "Middle position in 9x9 grid is *this*: " + toString() + sLS +
Arrays.toString(nineByNine[0]) + sLS +
Arrays.toString(nineByNine[1]) + sLS +
Arrays.toString(nineByNine[2]);
}
}
public class GridPosDemo {
private static final int[][] GRID = new int[][] {
{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1},
{0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1},
{1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1,0,1,0,1},
{1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1},
{1,0,1,0,1,1,1,0,1,0,1,1,1,1,1,1,1,1,1,0,1,0,1,1,1,0,1,0,1,1,1,1,1,0,1,1,1,0,1,0,1,0,1,1,1,0,1,1,1,0,1},
{1,0,1,0,1,0,1,0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,1,0,0,0,0,0,1,0,0,0,1},
{1,0,1,1,1,0,1,0,1,1,1,0,1,0,1,0,1,0,1,1,1,1,1,0,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,1,1,0,1,0,1},
{1,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,1,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,1},
{1,1,1,0,1,1,1,1,1,1,1,1,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,1,1,1,1,1,1,0,1,0,1,0,1,1,1,0,1,1,1,1,1,1,1,0,1},
{1,0,1,0,1,0,0,0,0,0,0,0,1,0,1,0,1,0,1,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,1},
{1,0,1,0,1,0,1,1,1,1,1,0,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1,1,1,1,1,0,1,0,1,1,1,0,1,0,1,1,1},
{1,0,1,0,1,0,0,0,1,0,1,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1},
{1,0,1,0,1,1,1,0,1,0,1,0,1,0,1,1,1,1,1,1,1,0,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,1,1},
{1,0,1,0,1,0,1,0,1,0,0,0,1,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1},
{1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,0,1,1,1,1,1,1,1,1,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,0,1},
{1,0,0,0,1,0,1,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,0,0,1},
{1,0,1,1,1,0,1,0,1,1,1,1,1,1,1,0,1,0,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,0,1,1,1,0,1,0,1,1,1,1,1,0,1,1,1,0,1},
{1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,0,0,0,0,1,0,1,0,1},
{1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,0,1,0,1,0,1,1,1,1,1,1,1,0,1,0,1,1,1,1,1,0,1,0,1,0,1,0,1,1,1,1,1,0,1,0,1},
{1,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,1},
{1,0,1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,0,1,1,1,0,1,0,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1,1,0,1,0,1,0,1,0,1},
{1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,1,0,1},
{1,1,1,0,1,0,1,1,1,0,1,1,1,0,1,0,1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,0,1,0,1,1,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1},
{1,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,1},
{1,0,1,1,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1,0,1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1},
{1,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,1},
{1,0,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,0,1,0,1,1,1,1,1,0,1,0,1,1,1,0,1,0,1,0,1},
{1,0,0,0,0,0,0,0,1,0,1,0,1,0,1,0,0,0,1,0,1,0,1,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,1,0,1,0,0,0,1,0,1,0,1},
{1,0,1,1,1,1,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,0,1,0,1,0,1,1,1,1,1,0,1,0,1,0,1,1,1,0,1,0,1,0,1,1,1,1,1,0,1},
{1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,1,0,0,0,1,0,1,0,0,0,0,0,1,0,1},
{1,1,1,1,1,0,1,1,1,1,1,1,1,0,1,0,1,0,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,0,1,0,1},
{1,0,0,0,1,0,1,0,0,0,1,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,1,0,1},
{1,0,1,1,1,0,1,1,1,0,1,0,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,0,1,0,1,0,1},
{1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,1},
{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1}};
private static final GridPosition GRID_HOLDER = new GridPosition(GRID);
public static final void main(String[] ignored) {
GridPosition pos = new GridPosition(0, 0);
System.out.println("start: " + pos);
pos = pos.getNeighbor(Direction.RIGHT);
System.out.println("right: " + pos);
pos = pos.getNeighbor(Direction.RIGHT);
System.out.println("right: " + pos);
pos = pos.getNeighbor(Direction.DOWN);
System.out.println("down: " + pos);
pos = pos.getNeighbor(Direction.DOWN);
System.out.println("down: " + pos);
pos = pos.getNeighbor(Direction.RIGHT);
System.out.println("right: " + pos);
pos = pos.getNeighbor(Direction.DOWN);
System.out.println("down: " + pos);
pos = pos.getNeighbor(Direction.LEFT);
System.out.println("left: " + pos);
pos = pos.getNeighbor(Direction.UP);
System.out.println("up: " + pos);
pos = pos.getNeighbor(Direction.UP);
System.out.println("up: " + pos);
System.out.println(pos.getNineByNine());
}
}

Time delay and JInput

OK, I don't know how to word this question, but maybe my code will spell out the problem:
public class ControllerTest
{
public static void main(String [] args)
{
GamePadController rockbandDrum = new GamePadController();
DrumMachine drum = new DrumMachine();
while(true)
{
try{
rockbandDrum.poll();
if(rockbandDrum.isButtonPressed(1)) //BLUE PAD HhiHat)
{
drum.playSound("hiHat.wav");
Thread.sleep(50);
}
if(rockbandDrum.isButtonPressed(2)) //GREEN PAD (Crash)
{
//Todo: Change to Crash
drum.playSound("hiHat.wav");
Thread.sleep(50);
}
//Etc....
}
}
}
public class DrumMachine
{
InputStream soundPlayer = null;
AudioStream audio = null;
static boolean running = true;
public void playSound(String soundFile)
{
//Tak a sound file as a paramater and then
//play that sound file
try{
soundPlayer = new FileInputStream(soundFile);
audio = new AudioStream(soundPlayer);
}
catch(FileNotFoundException e){
e.printStackTrace();
}
catch(IOException e){
e.printStackTrace();
}
AudioPlayer.player.start(audio);
}
//Etc... Methods for multiple audio clip playing
}
Now the problem is, if I lower the delay in the
Thread.sleep(50)
then the sound plays multiple times a second, but if I keep at this level or any higher, I could miss sounds being played...
It's an odd problem, where if the delay is too low, the sound loops. But if it's too high it misses playing sounds. Is this just a problem where I would need to tweak the settings, or is there any other way to poll the controller without looping sound?
Edit: If I need to post the code for polling the controller I will...
import java.io.*;
import net.java.games.input.*;
import net.java.games.input.Component.POV;
public class GamePadController
{
public static final int NUM_BUTTONS = 13;
// public stick and hat compass positions
public static final int NUM_COMPASS_DIRS = 9;
public static final int NW = 0;
public static final int NORTH = 1;
public static final int NE = 2;
public static final int WEST = 3;
public static final int NONE = 4; // default value
public static final int EAST = 5;
public static final int SW = 6;
public static final int SOUTH = 7;
public static final int SE = 8;
private Controller controller;
private Component[] comps; // holds the components
// comps[] indices for specific components
private int xAxisIdx, yAxisIdx, zAxisIdx, rzAxisIdx;
// indices for the analog sticks axes
private int povIdx; // index for the POV hat
private int buttonsIdx[]; // indices for the buttons
private Rumbler[] rumblers;
private int rumblerIdx; // index for the rumbler being used
private boolean rumblerOn = false; // whether rumbler is on or off
public GamePadController()
{
// get the controllers
ControllerEnvironment ce =
ControllerEnvironment.getDefaultEnvironment();
Controller[] cs = ce.getControllers();
if (cs.length == 0) {
System.out.println("No controllers found");
System.exit(0);
}
else
System.out.println("Num. controllers: " + cs.length);
// get the game pad controller
controller = findGamePad(cs);
System.out.println("Game controller: " +
controller.getName() + ", " +
controller.getType());
// collect indices for the required game pad components
findCompIndices(controller);
findRumblers(controller);
} // end of GamePadController()
private Controller findGamePad(Controller[] cs)
/* Search the array of controllers until a suitable game pad
controller is found (eith of type GAMEPAD or STICK).
*/
{
Controller.Type type;
int i = 0;
while(i < cs.length) {
type = cs[i].getType();
if ((type == Controller.Type.GAMEPAD) ||
(type == Controller.Type.STICK))
break;
i++;
}
if (i == cs.length) {
System.out.println("No game pad found");
System.exit(0);
}
else
System.out.println("Game pad index: " + i);
return cs[i];
} // end of findGamePad()
private void findCompIndices(Controller controller)
/* Store the indices for the analog sticks axes
(x,y) and (z,rz), POV hat, and
button components of the controller.
*/
{
comps = controller.getComponents();
if (comps.length == 0) {
System.out.println("No Components found");
System.exit(0);
}
else
System.out.println("Num. Components: " + comps.length);
// get the indices for the axes of the analog sticks: (x,y) and (z,rz)
xAxisIdx = findCompIndex(comps, Component.Identifier.Axis.X, "x-axis");
yAxisIdx = findCompIndex(comps, Component.Identifier.Axis.Y, "y-axis");
zAxisIdx = findCompIndex(comps, Component.Identifier.Axis.Z, "z-axis");
rzAxisIdx = findCompIndex(comps, Component.Identifier.Axis.RZ, "rz-axis");
// get POV hat index
povIdx = findCompIndex(comps, Component.Identifier.Axis.POV, "POV hat");
findButtons(comps);
} // end of findCompIndices()
private int findCompIndex(Component[] comps,
Component.Identifier id, String nm)
/* Search through comps[] for id, returning the corresponding
array index, or -1 */
{
Component c;
for(int i=0; i < comps.length; i++) {
c = comps[i];
if ((c.getIdentifier() == id) && !c.isRelative()) {
System.out.println("Found " + c.getName() + "; index: " + i);
return i;
}
}
System.out.println("No " + nm + " component found");
return -1;
} // end of findCompIndex()
private void findButtons(Component[] comps)
/* Search through comps[] for NUM_BUTTONS buttons, storing
their indices in buttonsIdx[]. Ignore excessive buttons.
If there aren't enough buttons, then fill the empty spots in
buttonsIdx[] with -1's. */
{
buttonsIdx = new int[NUM_BUTTONS];
int numButtons = 0;
Component c;
for(int i=0; i < comps.length; i++) {
c = comps[i];
if (isButton(c)) { // deal with a button
if (numButtons == NUM_BUTTONS) // already enough buttons
System.out.println("Found an extra button; index: " + i + ". Ignoring it");
else {
buttonsIdx[numButtons] = i; // store button index
System.out.println("Found " + c.getName() + "; index: " + i);
numButtons++;
}
}
}
// fill empty spots in buttonsIdx[] with -1's
if (numButtons < NUM_BUTTONS) {
System.out.println("Too few buttons (" + numButtons +
"); expecting " + NUM_BUTTONS);
while (numButtons < NUM_BUTTONS) {
buttonsIdx[numButtons] = -1;
numButtons++;
}
}
} // end of findButtons()
private boolean isButton(Component c)
/* Return true if the component is a digital/absolute button, and
its identifier name ends with "Button" (i.e. the
identifier class is Component.Identifier.Button).
*/
{
if (!c.isAnalog() && !c.isRelative()) { // digital and absolute
String className = c.getIdentifier().getClass().getName();
// System.out.println(c.getName() + " identifier: " + className);
if (className.endsWith("Button"))
return true;
}
return false;
} // end of isButton()
private void findRumblers(Controller controller)
/* Find the rumblers. Use the last rumbler for making vibrations,
an arbitrary decision. */
{
// get the game pad's rumblers
rumblers = controller.getRumblers();
if (rumblers.length == 0) {
System.out.println("No Rumblers found");
rumblerIdx = -1;
}
else {
System.out.println("Rumblers found: " + rumblers.length);
rumblerIdx = rumblers.length-1; // use last rumbler
}
} // end of findRumblers()
// ----------------- polling and getting data ------------------
public void poll()
// update the component values in the controller
{
controller.poll();
}
public int getXYStickDir()
// return the (x,y) analog stick compass direction
{
if ((xAxisIdx == -1) || (yAxisIdx == -1)) {
System.out.println("(x,y) axis data unavailable");
return NONE;
}
else
return getCompassDir(xAxisIdx, yAxisIdx);
} // end of getXYStickDir()
public int getZRZStickDir()
// return the (z,rz) analog stick compass direction
{
if ((zAxisIdx == -1) || (rzAxisIdx == -1)) {
System.out.println("(z,rz) axis data unavailable");
return NONE;
}
else
return getCompassDir(zAxisIdx, rzAxisIdx);
} // end of getXYStickDir()
private int getCompassDir(int xA, int yA)
// Return the axes as a single compass value
{
float xCoord = comps[ xA ].getPollData();
float yCoord = comps[ yA ].getPollData();
// System.out.println("(x,y): (" + xCoord + "," + yCoord + ")");
int xc = Math.round(xCoord);
int yc = Math.round(yCoord);
// System.out.println("Rounded (x,y): (" + xc + "," + yc + ")");
if ((yc == -1) && (xc == -1)) // (y,x)
return NW;
else if ((yc == -1) && (xc == 0))
return NORTH;
else if ((yc == -1) && (xc == 1))
return NE;
else if ((yc == 0) && (xc == -1))
return WEST;
else if ((yc == 0) && (xc == 0))
return NONE;
else if ((yc == 0) && (xc == 1))
return EAST;
else if ((yc == 1) && (xc == -1))
return SW;
else if ((yc == 1) && (xc == 0))
return SOUTH;
else if ((yc == 1) && (xc == 1))
return SE;
else {
System.out.println("Unknown (x,y): (" + xc + "," + yc + ")");
return NONE;
}
} // end of getCompassDir()
public int getHatDir()
// Return the POV hat's direction as a compass direction
{
if (povIdx == -1) {
System.out.println("POV hat data unavailable");
return NONE;
}
else {
float povDir = comps[povIdx].getPollData();
if (povDir == POV.CENTER) // 0.0f
return NONE;
else if (povDir == POV.DOWN) // 0.75f
return SOUTH;
else if (povDir == POV.DOWN_LEFT) // 0.875f
return SW;
else if (povDir == POV.DOWN_RIGHT) // 0.625f
return SE;
else if (povDir == POV.LEFT) // 1.0f
return WEST;
else if (povDir == POV.RIGHT) // 0.5f
return EAST;
else if (povDir == POV.UP) // 0.25f
return NORTH;
else if (povDir == POV.UP_LEFT) // 0.125f
return NW;
else if (povDir == POV.UP_RIGHT) // 0.375f
return NE;
else { // assume center
System.out.println("POV hat value out of range: " + povDir);
return NONE;
}
}
} // end of getHatDir()
public boolean[] getButtons()
/* Return all the buttons in a single array. Each button value is
a boolean. */
{
boolean[] buttons = new boolean[NUM_BUTTONS];
float value;
for(int i=0; i < NUM_BUTTONS; i++) {
value = comps[ buttonsIdx[i] ].getPollData();
buttons[i] = ((value == 0.0f) ? false : true);
}
return buttons;
} // end of getButtons()
public boolean isButtonPressed(int pos)
/* Return the button value (a boolean) for button number 'pos'.
pos is in the range 1-NUM_BUTTONS to match the game pad
button labels.
*/
{
if ((pos < 1) || (pos > NUM_BUTTONS)) {
System.out.println("Button position out of range (1-" +
NUM_BUTTONS + "): " + pos);
return false;
}
if (buttonsIdx[pos-1] == -1) // no button found at that pos
return false;
float value = comps[ buttonsIdx[pos-1] ].getPollData();
// array range is 0-NUM_BUTTONS-1
return ((value == 0.0f) ? false : true);
} // end of isButtonPressed()
// ------------------- Trigger a rumbler -------------------
public void setRumbler(boolean switchOn)
// turn the rumbler on or off
{
if (rumblerIdx != -1) {
if (switchOn)
rumblers[rumblerIdx].rumble(0.8f); // almost full on for last rumbler
else // switch off
rumblers[rumblerIdx].rumble(0.0f);
rumblerOn = switchOn; // record rumbler's new status
}
} // end of setRumbler()
public boolean isRumblerOn()
{ return rumblerOn; }
} // end of GamePadController class

I think you are using the wrong design pattern here. You should use the observer pattern for this type of thing.
A polling loop not very efficient, and as you've noticed doesn't really yield the desired results.
I'm not sure what you are using inside your objects to detect if a key is pressed, but if it's a GUI architecture such as Swing or AWT it will be based on the observer pattern via the use of EventListeners, etc.

Here is a (slightly simplified) Observer-pattern
applied to your situation.
The advantage of this design is that when a button
is pressed and hold, method 'buttonChanged' will
still only be called once, instead of start
'repeating' every 50 ms.
public static final int BUTTON_01 = 0x00000001;
public static final int BUTTON_02 = 0x00000002;
public static final int BUTTON_03 = 0x00000004;
public static final int BUTTON_04 = 0x00000008; // hex 8 == dec 8
public static final int BUTTON_05 = 0x00000010; // hex 10 == dec 16
public static final int BUTTON_06 = 0x00000020; // hex 20 == dec 32
public static final int BUTTON_07 = 0x00000040; // hex 40 == dec 64
public static final int BUTTON_08 = 0x00000080; // etc.
public static final int BUTTON_09 = 0x00000100;
public static final int BUTTON_10 = 0x00000200;
public static final int BUTTON_11 = 0x00000400;
public static final int BUTTON_12 = 0x00000800;
private int previousButtons = 0;
void poll()
{
rockbandDrum.poll();
handleButtons();
}
private void handleButtons()
{
boolean[] buttons = getButtons();
int pressedButtons = getPressedButtons(buttons);
if (pressedButtons != previousButtons)
{
buttonChanged(pressedButtons); // Notify 'listener'.
previousButtons = pressedButtons;
}
}
public boolean[] getButtons()
{
// Return all the buttons in a single array. Each button-value is a boolean.
boolean[] buttons = new boolean[MAX_NUMBER_OF_BUTTONS];
float value;
for (int i = 0; i < MAX_NUMBER_OF_BUTTONS-1; i++)
{
int index = buttonsIndex[i];
if (index < 0) { continue; }
value = comps[index].getPollData();
buttons[i] = ((value == 0.0f) ? false : true);
}
return buttons;
}
private int getPressedButtons(boolean[] array)
{
// Mold all pressed buttons into a single number by OR-ing their values.
int pressedButtons = 0;
int i = 1;
for (boolean isBbuttonPressed : array)
{
if (isBbuttonPressed) { pressedButtons |= getOrValue(i); }
i++;
}
return pressedButtons;
}
private int getOrValue(int btnNumber) // Get a value to 'OR' with.
{
int btnValue = 0;
switch (btnNumber)
{
case 1 : btnValue = BUTTON_01; break;
case 2 : btnValue = BUTTON_02; break;
case 3 : btnValue = BUTTON_03; break;
case 4 : btnValue = BUTTON_04; break;
case 5 : btnValue = BUTTON_05; break;
case 6 : btnValue = BUTTON_06; break;
case 7 : btnValue = BUTTON_07; break;
case 8 : btnValue = BUTTON_08; break;
case 9 : btnValue = BUTTON_09; break;
case 10 : btnValue = BUTTON_10; break;
case 11 : btnValue = BUTTON_11; break;
case 12 : btnValue = BUTTON_12; break;
default : assert false : "Invalid button-number";
}
return btnValue;
}
public static boolean checkButton(int pressedButtons, int buttonToCheckFor)
{
return (pressedButtons & buttonToCheckFor) == buttonToCheckFor;
}
public void buttonChanged(int buttons)
{
if (checkButton(buttons, BUTTON_01)
{
drum.playSound("hiHat.wav");
}
if (checkButton(buttons, BUTTON_02)
{
drum.playSound("crash.wav");
}
}

Please post more information about the GamePadController class that you are using.
More than likely, that same library will offer an "event" API, where a "callback" that you register with a game pad object will be called as soon as the user presses a button. With this kind of setup, the "polling" loop is in the framework, not your application, and it can be much more efficient, because it uses signals from the hardware rather than a busy-wait polling loop.
Okay, I looked at the JInput API, and it is not really event-driven; you have to poll it as you are doing. Does the sound stop looping when you release the button? If so, is your goal to have the sound play just once, and not again until the button is release and pressed again? In that case, you'll need to track the previous button state each time through the loop.
Human response time is about 250 ms (for an old guy like me, anyway). If you are polling every 50 ms, I'd expect the controller to report the button depressed for several iterations of the loop. Can you try something like this:
boolean played = false;
while (true) {
String sound = null;
if (controller.isButtonPressed(1))
sound = "hiHat.wav";
if (controller.isButtonPressed(2))
sound = "crash.wav";
if (sound != null) {
if (!played) {
drum.playSound(sound);
played = true;
}
} else {
played = false;
}
Thread.sleep(50);
}

Null Pointer Error Again

So I have this compiler class that compiles some .mjava files but others it fails on and wondering if anyone can help me figure out why. I have two methods that break for two different files. The first consts.mjava file I try to compile is:
// demo of true local and global variables
int glob0;
int glob1;
final int two = 2;
final int three = 3;
main() {
int loc1;
int loc2;
int loc3;
final int four = 4;
glob0 = three;
//print("glob0=", glob0, "\n");
loc1 = glob0*two+1;
glob1 = glob0*loc1;
loc2 = glob1+1;
loc3 = glob1*loc2/four;
print("glob0=", glob0, " (should be 3)\n");
print("glob1=", glob1, " (should be 21)\n");
print("loc1=", loc1, " (should be 7)\n");
print("loc2=", loc2, " (should be 22)\n");
print("loc3=", loc3, " (should be 115)\n");
}
When I try to compile this with my compiler class it breaks here:
private void compileFactor() {
if (isIdent(theToken)) {
String ident = theToken;
theToken = t.token();
IdentInfo theInfo = symTable.lookup(ident);
boolean its_a_variable = theInfo.isVar(); ***//Breaks Here for consts.mjava Null Exception***
int theAddr;
boolean isGlobal = theInfo.getIsGlobal();
int constValue;
int theNumber = 0;
if (its_a_variable) { // pld12: CHANGE THIS!!
theAddr = theInfo.getAddr();
isGlobal = theInfo.getIsGlobal();
if (theAddr == -1) t.error("undeclared identifier used in expr: "+ident);
if (isGlobal) cs.emit(Machine.LOAD, theAddr);
else cs.emit(Machine.LOADF, theAddr);
} else {
constValue = theInfo.getValue();
if (constValue == 0)
t.error("undeclared identifier used in expr: "+ident);
else {
cs.emitLOADINT(theNumber);
}
}
} else if (isNumber(theToken)) {
int theNumber = new Integer(theToken).intValue();
cs.emitLOADINT(theNumber);
theToken = t.token();
} else if (equals(theToken, "(")) {
accept("(");
compileExpr();
accept(")");
}
}
The next locs.mjava file I try to run breaks on this method:
private void compileIdentStmt() {
String ident = theToken;
boolean isGlobal = true;
int location = 0;
int entryPoint = 0;
IdentInfo varInfo = null;
if (!isIdent(ident)) t.error("expected identifier, got " + theToken);
theToken = t.token();
if (equals(theToken, "=")) {
accept("=");
varInfo = symTable.lookup(ident);
if (varInfo.isVar() == true) { ***//Breaks Here on locs.mjava: Null Exception***
location = varInfo.getAddr();
isGlobal = varInfo.getIsGlobal();
}
/*
if (varInfo==null) {
location = GHack(ident);
isGlobal = true;
}
if (location == -1) {
location = LHack(ident);
isGlobal = false;
}
/* */
compileExpr();
if (isGlobal) cs.emit(Machine.STOR, location);
else cs.emit(Machine.STORF, location);
accept(";");
} else if (equals(theToken, "(")) {
varInfo = symTable.lookup(ident);
if (varInfo.isProc() == true) {
entryPoint = varInfo.getEntryPoint();
dprint("call to function " + ident + "; generating JSR to location " + entryPoint);
accept("(");
}
/*
if (!equals(theToken, ")")) {
compileExpr();
while (equals(theToken, ",")) {
accept(",");
compileExpr();
}
}
/* */
accept(")");
accept(";");
cs.emit(Machine.JSR, entryPoint);
} else t.error("expected \"=\" or \"(\", got " + theToken);
}
I will even supply my lookup method from my symTable() to help:
public IdentInfo lookup(String ident) {
IdentInfo ii;
if (HMLocal != null) {
ii = HMLocal.get(ident);
if (ii != null) {
return ii;
}
ii = HMGlobal.get(ident);
if (ii != null) {
return ii;
}
}
return null;
}

If you're getting NullPointerExceptions then it's because theInfo and varInfo are null in your examples.

After
IdentInfo theInfo = symTable.lookup(ident);
you should check if theInfo is null before trying to work with it, since your lookup method clearly states it can return null.