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Why won't this PrintWriter populate this file?

I have a program which takes Giraffes from a text file, creates an ArrayList and LinkedList out of them (redundant, I know... LinkedList was a requirement of the second part of the assignment and I liked my ArrayList), sorts out who their parents are, and then is supposed to print a VBA macro out to a file.
The file (D:\\Java\\Macro.txt) is created, but it isn't populated with anything. Why isn't anything getting printed to the file? I think that there is an issue creating an array to return to the main function though.
I suspect that the problem is within the GetYearGroup method in the Herd Class, and the way that it is interfacing with the PrintWriter located on lines 51-83 of the Main class.
Here is the code:
HW4_Name.java (main)
package giraffe;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Scanner;
public class HW4_Name {
public static void main(String[] args) throws IOException {
ArrayList<Giraffe> giraffes = new ArrayList<>();
String temp[] = new String[13];
String header = "";
String fileLocation = "theHerd.txt";
File textFile = new File(fileLocation);
Scanner in = new Scanner(textFile);
if (textFile.canRead()) {
header = in.nextLine();
while (in.hasNextLine()) {
temp = in.nextLine().split("\\t", 13);
giraffes.add(new Giraffe(temp));
}
}
Herd herd = new Herd();
for(int i = 0; i < giraffes.size(); i++){
Giraffe g = giraffes.get(i);
herd.Add(g);
}
int nGiraffes = herd.Size();
for(int i = 0; i < nGiraffes; i++){
Giraffe g = herd.GetAt(i);
int nSire = g.getSireId();
if (nSire != -1){
g.setSire(herd.Find(nSire));
}
int nDam = g.getDamId();
if (nDam != -1){
g.setDam(herd.Find(nDam));
}
}
in.close();
PrintWriter pw = new PrintWriter("C:\\Java\\Macro.txt");
int nHeight = 500;
int nWidth = 900;
int nYearHeight = nHeight / 13;
int nRectangle = 0;
for(int i = 0; i < 13; i++){
int nLowYear = 50 + 5 * i;
Giraffe[] ThisGroup = herd.GetYearGroup(nLowYear, nLowYear + 5);
int nThisGroup = ThisGroup.length;
int nXSpacing = nWidth / (nThisGroup + 1);
int nYPos = 10 + nYearHeight * i;
for(int j = 0; j < nThisGroup; j++){
nRectangle++;
int nXPos = 10 + nXSpacing/2 + nXSpacing * j;
Giraffe g = ThisGroup[j];
g.setRectangle(nRectangle);
String strName = g.getName();
pw.println("Call Box(" + nXPos + ", " + nYPos + ", \"" +strName + "\")");
}
}
for(int i = 0; i < nGiraffes; i++){
Giraffe g = herd.GetAt(i);
Giraffe gSire = g.getSire();
if (gSire != null){
int nParentRectangle = gSire.getRectangle();
nRectangle = g.getRectangle();
if (nParentRectangle > 0 && nRectangle > 0){
pw.println("Call DadLine(" + nParentRectangle + ", " + nRectangle + ")");
}
}
Giraffe gDam = g.getDam();
if(gDam != null){
int nParentRectangle = gDam.getRectangle();
if (nParentRectangle > 0 && nRectangle > 0){
pw.println("Call MomLine(" + nParentRectangle + ", " + nRectangle + ")");
}
}
}
pw.close();
}
}
Giraffe.java
package giraffe;
import java.util.ArrayList;
public class Giraffe extends Object {
private String birthLocation, subSpecies, zoo, city, state, event, name,
localId, sex, eachGiraffe;
private int gId, birthYear, sireId, damId, gRectangle;
private Giraffe gSire, gDam;
public Giraffe(String array[]){
this.sex = String.format("%-1s",array[1]);
this.birthLocation = String.format("%-12s",array[5]);
this.localId = String.format("%-7s",array[6]);
this.name = String.format("%-20s",array[7]);
this.subSpecies = String.format("%-14s",array[8]);
this.zoo = String.format("%-35s",array[9]);
this.city = String.format("%-17s",array[10]);
this.state = String.format("%-13s",array[11]);
this.event = String.format("%-7s",array[12]);
this.gId = Integer.parseInt(array[0]);
this.birthYear = Integer.parseInt(array[2].substring(0,4));
if(array[3].equals("WILD") || array[3].equals("UNK")){
this.sireId = -1;
}
else{
this.sireId = Integer.parseInt(array[3]);
}
if(array[4].equals("WILD") || array[4].equals("UNK")){
this.damId = -1;
}
else{
this.damId = Integer.parseInt(array[4]);
}
}
public String getName(){
return this.name;
}
public int getId(){
return gId;
}
public int getBirthYear(){
return birthYear;
}
public int getSireId(){
return sireId;
}
public int getDamId(){
return damId;
}
public Giraffe getSire(){
return gSire;
}
public int getRectangle(){
return gRectangle;
}
public Giraffe getDam(){
return gDam;
}
public void setSire(Giraffe nSire){
this.gSire = nSire;
}
public void setDam(Giraffe nDam){
this.gDam = nDam;
}
public void setRectangle(int nRectangle){
this.gRectangle = nRectangle;
}
public String toString(){
eachGiraffe = ("" + this.gId);
return eachGiraffe;
}
}
Herd.java
package giraffe;
public class Herd extends LinkedList{
public Herd(){
}
public void Add(Giraffe g){
InsertRight(g);
}
public Giraffe Find(int idNumber){
Giraffe g = null;
Node currNode = start;
while(currNode != null && currNode.o.getId() != idNumber){
currNode = currNode.next;
}
if(currNode.o.getId() == idNumber){
g = currNode.o;
}
return g;
}
public Giraffe GetAt(int nIndex){
Giraffe g = null;
Node currNode = start;
for(int i = 0; i < nIndex; i++){
if(currNode != null){
currNode = currNode.next;
}
}
g = currNode.o;
return g;
}
public Giraffe[] GetYearGroup(int nBegin, int nEnd){
int nGiraffes = Size();
int nInGroup = 0;
for(int i = 0; i < nGiraffes; i++){
Giraffe g = GetAt(i);
int nBirthYear = g.getBirthYear();
if (nBegin <= nBirthYear && nBirthYear < nEnd){
nInGroup++;
}
}
Giraffe[] gary = new Giraffe[nInGroup];
nInGroup = 0;
for(int i = 0; i < nGiraffes; i ++){
Giraffe g = GetAt(i);
int nBirthYear = g.getBirthYear();
if(nBegin <= nBirthYear && nBirthYear < nEnd){
gary[nInGroup] = g;
nInGroup++;
}
}
return gary;
}
}
LinkedList.java
package giraffe;
public class LinkedList {
protected Node start;
private int errorReturn;
public LinkedList(){
start = null;
}
public LinkedList(int errorValue){
start = null;
errorReturn = errorValue;
System.out.println(errorReturn);
}
public boolean isEmpty(){
return (start == null);
}
public void InsertRight(Giraffe data){
Node currNode;
if (start == null){
start = new Node(data,start);
}
else{
currNode = start;
while (currNode.next != null){
currNode = currNode.next;
}
currNode.next = new Node (data, null);
}
}
public int Size(){
int length = 0;
Node currNode = start;
while(currNode != null){
length++;
currNode = currNode.next;
}
return length;
}
public void Display(){
Node currNode = start;
System.out.println("List contents: ");
while (currNode != null){
currNode = currNode.next;
}
System.out.println("--------------------------");
}
}
Node.java
package giraffe;
public class Node {
Giraffe o;
Node next;
public Node(Giraffe giraffe, Node nextNode){
o = giraffe;
next = nextNode;
}
}
Solution
Thank you to durron597 for pointing out that the birthYear function was not comparable to the GetYearGroup function.
Replacing:
for(int i = 0; i < 13; i++){
int nLowYear = 50 + 5 * i;
With:
for(int i = 0; i < 13; i++){
int nLowYear = 1950 + 5 * i;
Resolved the issue.

I see two problems, both of which could result in the things you're seeing:
You are outputting to the C:\\Java\\Macro.txt directory, but you are using a relative path to find your theHerd.txt. Try changing your theHerd.txt file to an absolute path, or use Class.getResourceAsStream() if the file is on your classpath.
Use a debugger to see if the Giraffe objects are getting created at all
Your birth year check seems really weird:
for(int i = 0; i < 13; i++){
int nLowYear = 50 + 5 * i;
Giraffe[] ThisGroup = herd.GetYearGroup(nLowYear, nLowYear + 5);
This is only going to check years in the range 50, 55, up to 115. However, in your Giraffe class, you do this:
this.birthYear = Integer.parseInt(array[2].substring(0,4));
This is only going to work (i.e. not throw an ArrayIndexOutOfBounds exception) for 4 digit date years, none of which are in the range 50-115. However, if you set your year to a value like 0073 (you must put the leading zeroes) then your program will print results like Call Box(235, 162, "GiraffeName "). You probably want to change that 50 to 1950.
Your program has other code smells; I suggest reading things like (in order of increasing time commitment):
Java Encapsulation Concept not clear
Java naming conventions
Single Responsibility Principle
Clean Code, by Robert Martin
But these two bits of code should get you started.

Why do object arrays in my ArrayList fail to retain their values?

I am creating a program in Java to simulate evolution. The way I have it set up, each generation is composed of an array of Organism objects. Each of these arrays is an element in the ArrayList orgGenerations. Each generation, of which there could be any amount before all animals die, can have any amount of Organism objects.
For some reason, in my main loop when the generations are going by, I can have this code without errors, where allOrgs is the Organism array of the current generation and generationNumber is the number generations since the first.
orgGenerations.add(allOrgs);
printOrgs(orgGenerations.get(generationNumber));
printOrgs is a method to display an Organism array, where speed and strength are Organism Field variables:
public void printOrgs(Organism[] list)
{
for (int x=0; x<list.length; x++)
{
System.out.println ("For organism number: " + x + ", speed is: " + list[x].speed + ", and strength is " + list[x].strength + ".");
}
}
Later on, after this loop, when I am trying to retrieve the data to display, I call this very similar code:
printOrgs(orgGenerations.get(0));
This, and every other array in orgGenerations, return a null pointer exception on the print line of the for loop. Why are the Organism objects loosing their values?
Alright, here is all of the code from my main Simulation class. I admit, it might be sort of a mess. The parts that matter are the start and simulator methods. The battle ones are not really applicable to this problem. I think.
import java.awt.FlowLayout;
import java.util.*;
import javax.swing.JFrame;
public class Simulator {
//variables for general keeping track
static Organism[] allOrgs;
static ArrayList<Organism[]> orgGenerations = new ArrayList <Organism[]>();
ArrayList<Integer> battleList = new ArrayList<Integer>();
int deathCount;
boolean done;
boolean runOnce;
//setup
Simulator()
{
done = false;
Scanner asker = new Scanner(System.in);
System.out.println("Input number of organisms for the simulation: ");
int numOfOrgs = asker.nextInt();
asker.close();
Organism[] orgArray = new Organism[numOfOrgs];
for (int i=0; i<numOfOrgs; i++)
{
orgArray[i] = new Organism();
}
allOrgs = orgArray;
}
//graphsOrgs
public void graphOrgs() throws InterruptedException
{
JFrame f = new JFrame("Evolution");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(1000,500);
f.setVisible(true);
Drawer bars = new Drawer();
//System.out.println(orgGenerations.size());
for (int iterator=0;iterator<(orgGenerations.size()-1); iterator++)
{
printOrgs(orgGenerations.get(0));
//The 0 can be any number, no matter what I do it wont work
//System.out.println("first");
f.repaint();
bars.data = orgGenerations.get(iterator);
f.add(bars);
//System.out.println("before");
Thread.sleep(1000);
//System.out.println("end");
}
}
//prints all Orgs and their statistics
public void printOrgs(Organism[] list)
{
System.out.println("Number Of Organisms: " + list.length);
for (int x=0; x<list.length; x++)
{
System.out.println ("For organism number: " + x + ", speed is: " + list[x].speed + ", and strength is " + list[x].strength + ".");
}
System.out.println();
}
//general loop for the organisms lives
public void start(int reproductionTime) throws InterruptedException
{
int generationNumber = 0;
orgGenerations.add(allOrgs);
printOrgs(orgGenerations.get(0));
generationNumber++;
while(true)
{
deathCount = 0;
for(int j=0; j<reproductionTime; j++)
{
battleList.clear();
for(int m=0; m<allOrgs.length; m++)
{
if (allOrgs[m].alive == true)
oneYearBattleCheck(m);
}
battle();
}
reproduction();
if (done == true)
break;
orgGenerations.add(allOrgs);
printOrgs(orgGenerations.get(generationNumber));
generationNumber++;
}
printOrgs(orgGenerations.get(2));
}
//Checks if they have to fight this year
private void oneYearBattleCheck(int m)
{
Random chaos = new Random();
int speedMod = chaos.nextInt(((int)Math.ceil(allOrgs[m].speed/5.0))+1);
int speedSign = chaos.nextInt(2);
if (speedSign == 0)
speedSign--;
speedMod *= speedSign;
int speed = speedMod + allOrgs[m].speed;
if (speed <= 0)
speed=1;
Random encounter = new Random();
boolean battle = false;
int try1 =(encounter.nextInt(speed));
int try2 =(encounter.nextInt(speed));
int try3 =(encounter.nextInt(speed));
int try4 =(encounter.nextInt(speed));
if (try1 == 0 || try2 == 0 || try3 == 0 || try4 == 0 )
{
battle = true;
}
if(battle == true)
{
battleList.add(m);
}
}
//Creates the matches and runs the battle
private void battle()
{
Random rand = new Random();
if (battleList.size()%2 == 1)
{
int luckyDuck = rand.nextInt(battleList.size());
battleList.remove(luckyDuck);
}
for(int k=0; k<(battleList.size()-1);)
{
int competitor1 = rand.nextInt(battleList.size());
battleList.remove(competitor1);
int competitor2 = rand.nextInt(battleList.size());
battleList.remove(competitor2);
//Competitor 1 strength
int strengthMod = rand.nextInt(((int)Math.ceil(allOrgs[competitor1].strength/5.0))+1);
int strengthSign = rand.nextInt(2);
if (strengthSign == 0)
strengthSign--;
strengthMod *= strengthSign;
int comp1Strength = strengthMod + allOrgs[competitor1].strength;
//Competitor 2 strength
strengthMod = rand.nextInt(((int)Math.ceil(allOrgs[competitor2].strength/5.0))+1);
strengthSign = rand.nextInt(2);
if (strengthSign == 0)
strengthSign--;
strengthMod *= strengthSign;
int comp2Strength = strengthMod + allOrgs[competitor2].strength;
//Fight!
if (comp1Strength>comp2Strength)
{
allOrgs[competitor1].life ++;
allOrgs[competitor2].life --;
}
else if (comp2Strength>comp1Strength)
{
allOrgs[competitor2].life ++;
allOrgs[competitor1].life --;
}
if (allOrgs[competitor1].life == 0)
{
allOrgs[competitor1].alive = false;
deathCount++;
}
if (allOrgs[competitor2].life == 0)
{
allOrgs[competitor2].alive = false;
deathCount ++ ;
}
}
}
//New organisms
private void reproduction()
{
//System.out.println("Number of deaths: " + deathCount + "\n");
if (deathCount>=(allOrgs.length-2))
{
done = true;
return;
}
ArrayList<Organism> tempOrgs = new ArrayList<Organism>();
Random chooser = new Random();
int count = 0;
while(true)
{
int partner1 = 0;
int partner2 = 0;
boolean partnerIsAlive = false;
boolean unluckyDuck = false;
//choose partner1
while (partnerIsAlive == false)
{
partner1 = chooser.nextInt(allOrgs.length);
if (allOrgs[partner1] != null)
{
if (allOrgs[partner1].alive == true)
{
partnerIsAlive = true;
}
}
}
count++;
//System.out.println("Count 2: " + count);
partnerIsAlive = false;
//choose partner2
while (partnerIsAlive == false)
{
if (count+deathCount == (allOrgs.length))
{
unluckyDuck=true;
break;
}
partner2 = chooser.nextInt(allOrgs.length);
if (allOrgs[partner2] != null)
{
if (allOrgs[partner2].alive == true)
{
partnerIsAlive = true;
}
}
}
if (unluckyDuck == false)
count++;
//System.out.println("count 2: " + count);
if (unluckyDuck == false)
{
int numOfChildren = (chooser.nextInt(4)+1);
for (int d=0; d<numOfChildren; d++)
{
tempOrgs.add(new Organism(allOrgs[partner1].speed, allOrgs[partner2].speed, allOrgs[partner1].strength, allOrgs[partner2].strength ));
}
allOrgs[partner1] = null;
allOrgs[partner2] = null;
}
if (count+deathCount == (allOrgs.length))
{
Arrays.fill(allOrgs, null);
allOrgs = tempOrgs.toArray(new Organism[tempOrgs.size()-1]);
break;
}
//System.out.println(count);
}
}
}
Main method:
public class Runner {
public static void main(String[] args) throws InterruptedException {
Simulator sim = new Simulator();
int lifeSpan = 20;
sim.start(lifeSpan);
sim.graphOrgs();
}
}
Organism class:
import java.util.Random;
public class Organism {
static Random traitGenerator = new Random();
int life;
int speed;
int strength;
boolean alive;
Organism()
{
speed = (traitGenerator.nextInt(49)+1);
strength = (50-speed);
life = 5;
alive = true;
}
Organism(int strength1, int strength2, int speed1, int speed2)
{
Random gen = new Random();
int speedMod = gen.nextInt(((int)Math.ceil((speed1+speed2)/10.0))+1);
int speedSign = gen.nextInt(2);
if (speedSign == 0)
speedSign--;
speedMod *= speedSign;
//System.out.println(speedMod);
int strengthMod = gen.nextInt(((int)Math.ceil((strength1+strength2)/10.0))+1);
int strengthSign = gen.nextInt(2);
if (strengthSign == 0)
strengthSign--;
strengthMod *= strengthSign;
//System.out.println(strengthMod);
strength = (((int)((strength1+strength2)/2.0))+ strengthMod);
speed = (((int)((speed1+speed2)/2.0))+ speedMod);
alive = true;
life = 5;
}
}
The problem lies in the graphOrgs class when I try to print to check if it is working in preparation for graphing the results. This is when it returns the error. When I try placing the print code in other places in the Simulator class the same thing occurs, a null pointer error. This happens even if it is just after the for loop where the element has been established.

You have code that sets to null elements in your allOrgs array.
allOrgs[partner1] = null;
allOrgs[partner2] = null;
Your orgGenerations list contains the same allOrgs instance multiple times.
Therefore, when you write allOrgs[partner1] = null, the partner1'th element becomes null in all the list elements of orgGenerations, which is why the print method fails.
You should create a copy of the array (you can use Arrays.copy) each time you add a new generation to the list (and consider also creating copies of the Organism instances, if you want each generation to record the past state of the Organisms and not their final state).

CombSort implementation in java

I am using Comb Sort to sort out a given array of Strings. The code is :-
public static int combSort(String[] input_array) {
int gap = input_array.length;
double shrink = 1.3;
int numbOfComparisons = 0;
boolean swapped=true;
//while(!swapped && gap>1){
System.out.println();
while(!(swapped && gap==1)){
gap = (int)(gap/shrink);
if(gap<1){
gap=1;
}
int i = 0;
swapped = false;
String temp = "";
while((i+gap) < input_array.length){
numbOfComparisons++;
if(Compare(input_array[i], input_array[i+gap]) == 1){
temp = input_array[i];
input_array[i] = input_array[i+gap];
input_array[i+gap] = temp;
swapped = true;
System.out.println("gap: " + gap + " i: " + i);
ArrayUtilities.printArray(input_array);
}
i++;
}
}
ArrayUtilities.printArray(input_array);
return numbOfComparisons;
}
The problem is that while it sorts many arrays , it gets stuck in an infinite loop for some arrays, particularly small arrays. Compare(input_array[i], input_array[i+gap]) is a small method that returns 1 if s1>s2, returns -1 if s1

try this version. The string array is changed to integer array (I guess you can change it back to string version). The constant 1.3 is replaced with 1.247330950103979.
public class CombSort
{
private static final int PROBLEM_SIZE = 5;
static int[] in = new int[PROBLEM_SIZE];
public static void printArr()
{
for(int i=0;i<in.length;i++)
{
System.out.print(in[i] + "\t");
}
System.out.println();
}
public static void combSort()
{
int swap, i, gap=PROBLEM_SIZE;
boolean swapped = false;
printArr();
while ((gap > 1) || swapped)
{
if (gap > 1)
{
gap = (int)( gap / 1.247330950103979);
}
swapped = false;
for (i = 0; gap + i < PROBLEM_SIZE; ++i)
{
if (in[i] - in[i + gap] > 0)
{
swap = in[i];
in[i] = in[i + gap];
in[i + gap] = swap;
swapped = true;
}
}
}
printArr();
}
public static void main(String[] args)
{
for(int i=0;i<in.length;i++)
{
in[i] = (int) (Math.random()*PROBLEM_SIZE);
}
combSort();
}
}

Please find below implementation for comb sort in java.
public static void combSort(int[] elements) {
float shrinkFactor = 1.3f;
int postion = (int) (elements.length/shrinkFactor);
do {
int cursor = postion;
for(int i=0;cursor<elements.length;i++,cursor++) {
if(elements[i]>elements[cursor]) {
int temp = elements[cursor];
elements[cursor] = elements[i];
elements[i] = temp;
}
}
postion = (int) (postion/shrinkFactor);
}while(postion>=1);
}
Please review and let me know your's feedback.

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();
.

Random number - increase/decrease by 1

I'm working on a method, that takes steps between 3 and -3. My program will not print out the steps in a numerical order, and I can't quite figure out how to do it, and I can't find anything elsewhere.
public static final int SENTINEL = Math.abs(3);
public static void randomWalk(Random rand) {
int walk = 0;
while (walk != SENTINEL) {
walk = (rand.nextInt((3 - (-3)) + 1) - 3);
System.out.println("Position = " + walk);
}
}

If that is what you are looking for :
int walk = 0;
int randomStep = 0;
Random rand = new Random();
while (Math.abs(walk) != 3) {
randomStep = rand.nextInt(2) > 0 ? 1 : -1; // -1 or 1 with 50% probability
walk += randomStep;
System.out.print(walk + " ");
}
//sample output: -1 -2 -1 0 1 2 1 2 3

public static void randomWalk(Random rand) {
int walk = 0;
while (walk != SENTINEL) {
walk += rand.nextInt(3) - 1;
if(walk>3) walk = 3;
if(walk<-3) walk = -3;
System.out.println("Position = " + walk);
}
}

I guess you want this.
while (walk != SENTINEL) {
int walk = 0;
walk = (rand.nextInt((3 - (-3)) + 1) - 3);
System.out.println("Walk is = " + walk);
int temp = walk;
if (walk >= -3) {
System.out.println("Wlak plus = " + (temp + 1));
System.out.println("Wlak minus =" + (temp - 1));
}
}

Could this be what you are looking for?
package com.stackoverflow.random;
import java.util.Random;
public class Walking {
private final int bounds;
public Walking(int bounds) {
this.bounds = bounds;
}
private boolean isWithinBounds(int walk) {
return Math.abs(walk) < bounds;
}
public String randomWalk() {
int walk = 0;
StringBuilder sb = new StringBuilder();
while(isWithinBounds(walk)) {
sb.append(walk);
walk = getNextStep(walk);
}
return sb.toString();
}
private Random random = null;
private int getNextStep(int walk) {
if (random == null)
random = new Random();
boolean increase = random.nextBoolean();
return increase?++walk:--walk;
}
public static void main(String[] args) {
Walking app = new Walking(3);
System.out.println("walking: " + app.randomWalk());
}
}