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Converting multiple strings into one

I'm trying to convert multiple strings into one simple dialogue from a NPC. Basically what I'm trying to do is make a list of all the skills a player has 200M experience in and output it into a NPC dialogue.
OLD
if (componentId == OPTION_4) {
sendNPCDialogue(npcId, 9827, "You can prestige: "+maxedSkills()+"");
}
private String maxedSkills() {
return ""+attackMax()+""+strengthMax()+""+defenceMax()+"";
}
public String attackMax() {
if (player.getSkills().getXp(Skills.ATTACK) == 200000000)
return "Attack, ";
else
return "";
}
public String strengthMax() {
if (player.getSkills().getXp(Skills.STRENGTH) == 200000000)
return "Strength, ";
else
return "";
}
public String defenceMax() {
if (player.getSkills().getXp(Skills.DEFENCE) == 200000000)
return "Defence, ";
else
return "";
}
With that code I have it working, but that is a lot of code to add due to there being 25 different skills. How would I create a way to make all of the skills be referenced into one? Here are all of the skill names:
public static final String[] SKILL_NAME = { "Attack", "Defence", "Strength", "Constitution", "Ranged", "Prayer",
"Magic", "Cooking", "Woodcutting", "Fletching", "Fishing", "Firemaking", "Crafting", "Smithing", "Mining",
"Herblore", "Agility", "Thieving", "Slayer", "Farming", "Runecrafting", "Hunter", "Construction",
"Summoning", "Dungeoneering" };
New and working (for attack/strength/defence):
public static final int[] SKILL_TYPE = {Skills.ATTACK, Skills.STRENGTH, Skills.DEFENCE};
public String maxedSkills() {
StringBuffer sb = new StringBuffer();
for(int i = 0; i < SKILL_TYPE.length; i++) {
if (player.getSkills().getXp(i) == 200000000) {
if(sb.length()>0) sb.append(", ");
sb.append(Skills.SKILL_NAME[i]);
}
}
if(sb.length()>0) sb.append(".");
return sb.toString();
}

Simplest way would be to have a parameteried method that takes the Skill type as input. Here is how it would look like:
public String skillMax(Skills skill) {
if (player.getSkills().getXp(skill) == 200000000)
return skill.getName() + ", ";
else
return "";
}
The next thing to do is to provide a name to the skill in Skills enum. Something like this should work:
public enum Skills {
DEFENSE("Defense"), ...;
private String name;
Skills(String name) { this.name = name; }
String getName() { return this.name; }
}

Use a StringBuffer (thread safe) or a StringBuilder and do something like this.
....
public static final Skills[] SKILL_TYPE = {Skills.Attack, Skills.Defence, ...};
public String getBigString() {
StringBuffer sb = new StringBuffer();
int nSkills = 0, lSkill = 0;
for( int i = 0; i < SKILL_TYPE.length; i++ )
{
if( player.getSkills().getXp(SKILL_TYPE[i]) == K_SOMELEVEL ) {
if(nSkills > 0) sb.append(", ");
lSkill = sb.length(); // track position of last skill in string
nSkills += 1;
sb.append(SKILL_NAME[i]);
}
}
if( nSkills > 0 )
{
if( nSkills > 1 ) sb.insert( lSkill, "and ");
sb.append(".");
}
return sb.toString();
}

"Duplicate" entries in ArrayList?

i have this class thats going to fill a list with All employees that are pre made in an array. I can populate an ArrayList with employees but the only problem is that i get a few "Duplicate" entries, i use quotes cause they are not EXACTLY the same but they could share the same name or employee number but may not have the same hire year or salary ect.
heres the employee class :
public class Employee {
public String EmployeeName;
public String EmployeeNumber;
public int hireyear;
public double WeeklyEarning;
public Employee()
{
EmployeeName = null;
EmployeeNumber = null;
hireyear = 0;
WeeklyEarning = 0;
}
public static final String[] Empnum = new String[] {
"0001-A", "0002-B","0003-C","0004-D","0002-A",
"0003-B","0004-C","0005-D","0011-A", "0012-B",
"0013-C","0014-D","0121-A", "0122-B","0123-C",
"0321-A", "0312-B","1234-D","4321-C","1122-D"};
public static final String[] Ename = new String[] {
"Josh", "Alex", "Paul", "Jimmy", "Josh", "Gordan", "Neil", "Bob",
"Shiv", "James", "Jay", "Chris", "Michael", "Andrew", "Stuart",
"Dave","Benjamin","Dan","Brian","Michelle"};
public String getEmployeeName()
{
return this.EmployeeName;
}
public String getEmployeeNumber()
{
return this.EmployeeNumber;
}
public int gethireyear()
{
return this.hireyear;
}
public double getWeeklyEarning()
{
return this.WeeklyEarning;
}
public String setEmployeeName(String EName)
{
return this.EmployeeName = EName;
}
public String setEmployeeNumber(String ENumber)
{
return this.EmployeeNumber = ENumber;
}
public int setEmployeehireyear(int Ehireyear)
{
return this.hireyear = Ehireyear;
}
public double setEmployeeweeklyearning(double Eweeklyearning)
{
return this.WeeklyEarning = Eweeklyearning;
}
public String toString(){
String data = "\n Employee Name : " + EmployeeName + " \n Employee Number: " + EmployeeNumber + " \n Hire Year : " + hireyear + "\n Weekly Earnings : " + WeeklyEarning;
return data;
}
public boolean equals(Object o){
if(this == null){
return false;
}
if(this == o){
return true;
}
if(!(o instanceof Employee)){
return false;
}
Employee temp = (Employee) o;
if(this.getEmployeeName().equals(temp.getEmployeeName())){
return true;
}
if(this.getEmployeeNumber().equals(temp.getEmployeeNumber())){
return true;
}
if(this.gethireyear() == temp.gethireyear()){
return true;
}
if(this.getWeeklyEarning() == temp.getWeeklyEarning()){
return true;
}
return false;
}
}
Heres the generateList method that will populate the list:
public ArrayList<Employee> generateEmpList(){
empList = new ArrayList <Employee>();
Random empPicker = new Random();
for(int i = 0; i < 20; i++){
int id = empPicker.nextInt(20);
if(id < 12) // roll for production worker
{
//System.out.println("Adding Production Worker");
ProductionWorker temp = new ProductionWorker();
temp = temp.generateProductionWorker();
prodWorker = temp;
empList.add(prodWorker);
}
else //roll for Shift supervisor
{
//System.out.println("Adding Shift supervisor");
ShiftSupervisor supervisor = new ShiftSupervisor();
supervisor = supervisor.generateShiftSupervisor();
shiftWorker = supervisor;
empList.add(shiftWorker);
}
}
Iterator iterator = empList.iterator();
while (iterator.hasNext()) {
System.out.println("");
System.out.println(iterator.next());
}
return empList;
}
and also which could be helpful is the "generateProductionWorker()" and shiftSupervisor methods - to keep it short ill only post prod worker method cause they are basically the same:
public ProductionWorker generateProductionWorker(){
Random rng = new Random();
int numberOfEmployeeNames = Ename.length;
ProductionWorker tempPworker = new ProductionWorker();
String employeeName = Ename[rng.nextInt(numberOfEmployeeNames)];
tempPworker.setEmployeeName(employeeName);
int numberOfEmployeeNumbers = Empnum.length;
String employeeNumber = Empnum[rng.nextInt(numberOfEmployeeNumbers)];
tempPworker.setEmployeeNumber(employeeNumber);
int yearHired = rng.nextInt(35) + 1980;
tempPworker.setEmployeehireyear(yearHired);
double weeklySalary = rng.nextInt((100) * 100);
tempPworker.setEmployeeweeklyearning(weeklySalary);
int hourlyRate = rng.nextInt(20) + 10;
tempPworker.setHourlyRate(hourlyRate);
return tempPworker;
}
I'm sure I'm missing something trivial but any ideas why i get similar entries when i have a list of 20 names and numbers?
ex:
empname - josh
empnum - 0000-A
hireyear - 1994
salary - 40,000
empname - josh
empnum - 0000-A
hireyear - 1999
salary - 60,500
any advice would help, Thanks!

Look at the equals method in your Employee class. If their name are the same, you return true, which means these are equals. The same is for the other attributes. You must replace your if statements.

I agree with Georgi, you equals method is the culprit.
Currently it is returning true after the first if statement at the line that reads
if(this.getEmployeeName().equals(temp.getEmployeeName())){
return true;
}
Because it is a return statement it stops the method from continuing to the other statements. You might try this:
public boolean equals(Object o){
if(this == null){
return false;
}
if(this == o){
return true;
}
if(!(o instanceof Employee)){
return false;
}
//set all the elements in the array to false and change to true when true.
boolean [] doesItMatch = new boolean[4];
doesItMatch[0] = false;
doesItMatch[1] = false;
doesItMatch[2] = false;
doesItMatch[3] = false;
Employee temp = (Employee) o;
if(this.getEmployeeName().equals(temp.getEmployeeName())){
doesItMatch[0] = true;
}
if(this.getEmployeeNumber().equals(temp.getEmployeeNumber())){
doesItMatch[1] = true;
}
if(this.gethireyear() == temp.gethireyear()){
doesItMatch[2] = true;
}
if(this.getWeeklyEarning() == temp.getWeeklyEarning()){
doesItMatch[3] = true;
}
int check = 0;
//Now that you have checked all the values, check the array. Using a simple counter.
for(int i = 0; i < doesItMatch.length; i++){
if(doesItMatch[i]){
check++;
} else {
check--;
}
}
//The counter should be 4 when the if statements above are all true. Anything else is false.
if(check == 4){
return true;
} else {
return false;
}
}
This method now checks each of the attributes in the Employee class. (Name, Number, Hire year and so on. If you create more attributes to the class it is easy to add more elements to the array just be sure to set them to false.)
Hope this helps
This also would take a little maintenance if you expanded the Employee class so you might want to find a way to make it a little easier on yourself.

Can compare user input(scanner) and arrayList from Calendar?

I wanted to get only the available date not from the arrayList(Rental) but for arrayList(Resort). Unfortunately, I was unable to compare both and the output that I get from are the arrayList(Rental).
public static void listavailableResort(ArrayList resortList, ArrayList rentalList)
{
Resort rt;
Rental rl;
Person p;
boolean availresort = false;
boolean availrental = false;
//viewing available resortList from rentalList
for (int i = 0; i<resortList.size();i++)
{
availresort = true;
rt =(Resort)resortList.get(i);
for (int k = 0; k< rentalList.size();k++)
{
availrental = true;
rl = (Rental)rentalList.get(k);
//Compare between the user entered and the rentalList
//start is arrivaldate end is departuredate
if(((!(start.equals(rl.getarrivalDate())))&&(!(end.equals(rl.getDepartureDate()))))||((start.before(rl.getarrivalDate()))&&(end.before(rl.getDepartureDate()))) || ((start.after(rl.getarrivalDate())))&&(end.after(rl.getDepartureDate())))
{
rt = rl.getresort();
if (rt instanceof Chalet)
{
//how to check if two date are equals
Chalet t = (Chalet)rt;
System.out.println((i+1)+"\t"+t.getresortID()+"\t"+t.getblock()+"\t"+t.getunitNumber());
}
else if(rt instanceof Bungalow)
{
Bungalow b =(Bungalow)rt;
System.out.println((i+1)+"\t"+b.getresortID()+"\t\t"+b.getblock()+"\t\t\t\t"+b.getwifi()+"\t\t "+b.getrate());
}
}
else
{
if (rt instanceof Chalet)
{
//how to check if two date are equals
Chalet t = (Chalet)rt;
System.out.println((i+1)+"\t"+t.getresortID()+"\t"+t.getblock()+"\t"+t.getunitNumber());
}
else if(rt instanceof Bungalow)
{
Bungalow b =(Bungalow)rt;
System.out.println((i+1)+"\t"+b.getresortID()+"\t\t"+b.getblock()+"\t\t\t\t"+b.getwifi()+"\t\t "+b.getrate());
}
}
}
I apologize if the coding is messy... I just need to know how to compare the input(Scanner) and the arrayList(getting from the rentalList(arrivalDate and departuredate))
Many thks

How do I check if a class' return of a method equals null?

In my program, I have a while loop that will display a list of shops and asks for an input, which corresponds with the shop ID. If the user enters an integer outside the array of shops, created with a Shop class, it will exit the loop and continue. Inside this loop is another while loop which calls the sellItem method of my Shop class below:
public Item sellItem()
{
displayItems();
int indexID = Shop.getInput();
if (indexID <= -1 || indexID >= wares.length)
{
System.out.println("Null"); // Testing purposes
return null;
}
else
{
return wares[indexID];
}
}
private void displayItems()
{
System.out.println("Name\t\t\t\tWeight\t\t\t\tPrice");
System.out.println("0. Return to Shops");
for(int i = 0; i < wares.length; i++)
{
System.out.print(i + 1 + ". ");
System.out.println(wares[i].getName() + "\t\t\t\t" + wares[i].getWeight() + "\t\t\t\t" + wares[i].getPrice());
}
}
private static int getInput()
{
Scanner scanInput = new Scanner(System.in);
int itemID = scanInput.nextInt();
int indexID = itemID - 1;
return indexID;
}
The while loop in my main class method is as follows:
boolean exitAllShops = true;
while(exitAllShops)
{
System.out.println("Where would you like to go?\nEnter the number which corresponds with the shop.\n1. Pete's Produce\n2. Moore's Meats\n3. Howards Hunting\n4. Foster's Farming\n5. Leighton's Liquor\n6. Carter's Clothing\n7. Hill's Household Products\n8. Lewis' Livery, Animals, and Wagon supplies\n9. Dr. Miller's Medicine\n10. Leave Shops (YOU WILL NOT BE ABLE TO RETURN)");
int shopInput = scan.nextInt();
if(shopInput >= 1 && shopInput <= allShops.length)
{
boolean leaveShop = true;
while(leaveShop)
{
allShops[shopInput - 1].sellItem();
if(allShops == null)
{
System.out.println("still null"); // Testing purposes
leaveShop = false;
}
}
}
else
{
System.out.println("Are you sure you want to leave?\n1. Yes\n2. No");
int confirm = scan.nextInt();
if(confirm == 1)
{
exitAllShops = false;
}
}
The problem is here:
boolean leaveShop = true;
while(leaveShop)
{
allShops[shopInput - 1].sellItem();
if(allShops == null)
{
System.out.println("still null"); // Testing purposes
leaveShop = false;
}
}
No matter what I do, I can't get "still null" to print to confirm that I'm correctly calling the return statement of the method sellItem of the class Shop. What am I doing wrong?

After calling allShops[...].sellItem(), allShops is still a valid array reference -- there's no way it could be null! You probably want to test the return value from sellItem:
if(allShops[shopInput-1].sellItem() == null)

Infinite while loop in java, not reading in sentinel

I've had this problem throughout multiple programs, but I can't remember how I fixed it last time. In the second while loop in my body, the second sentinel value is never read in for some reason. I've been trying to fix it for a while now, thought I might see if anyone had any clue.
import java.text.DecimalFormat; // imports the decimal format
public class Car {
// Makes three instance variables.
private String make;
private int year;
private double price;
// Makes the an object that formats doubles.
public static DecimalFormat twoDecPl = new DecimalFormat("$0.00");
// Constructor that assigns the instance variables
// to the values that the user made.
public Car(String carMake,int carYear, double carPrice)
{
make = carMake;
year = carYear;
price = carPrice;
}
// Retrieves variable make.
public String getMake()
{
return make;
}
// Retrieves variable year.
public int getYear()
{
return year;
}
// Retrieves variable price.
public double getPrice()
{
return price;
}
// Checks if two objects are equal.
public boolean equals(Car c1, Car c2)
{
boolean b = false;
if(c1.getMake().equals(c2.getMake()) && c1.getPrice() == c2.getPrice() &&
c1.getYear() == c2.getYear())
{
b = true;
return b;
}
else
{
return b;
}
}
// Turns the object into a readable string.
public String toString()
{
return "Description of car:" +
"\n Make : " + make +
"\n Year : " + year +
"\n Price: " + twoDecPl.format(price);
}
}
import java.util.Scanner; // imports a scanner
public class CarSearch {
public static void main(String[] args)
{
// initializes all variables
Scanner scan = new Scanner(System.in);
final int SIZE_ARR = 30;
Car[] carArr = new Car[SIZE_ARR];
final String SENT = "EndDatabase";
String carMake = "";
int carYear = 0;
double carPrice = 0;
int count = 0;
int pos = 0;
final String SECSENT = "EndSearchKeys";
final boolean DEBUG_SW = true;
// Loop that goes through the first list of values.
// It then stores the values in an array, then uses the
// values to make an object.
while(scan.hasNext())
{
if(scan.hasNext())
{
carMake = scan.next();
}
else
{
System.out.println("ERROR - not a String");
System.exit(0);
}
if(carMake.equals(SENT))
{
break;
}
if(scan.hasNextInt())
{
carYear = scan.nextInt();
}
else
{
System.out.println("ERROR - not an int" + count);
System.exit(0);
}
if(scan.hasNextDouble())
{
carPrice = scan.nextDouble();
}
else
{
System.out.println("ERROR - not a double");
System.exit(0);
}
Car car1 = new Car(carMake, carYear, carPrice);
carArr[count] = car1;
count++;
}
// Calls the method debugSwitch to show the debug information.
debugSwitch(carArr, DEBUG_SW, count);
// Calls the method printData to print the database.
printData(carArr, count);
// Loops through the second group of values and stores them in key.
// Then, it searches for a match in the database.
**while(scan.hasNext())**
{
if(scan.hasNext())
{
carMake = scan.next();
}
else
{
System.out.println("ERROR - not a String");
System.exit(0);
}
if(carMake.equals(SECSENT))
{
break;
}
if(scan.hasNextInt())
{
carYear = scan.nextInt();
}
else
{
System.out.println("ERROR - not an int" + count);
System.exit(0);
}
if(scan.hasNextDouble())
{
carPrice = scan.nextDouble();
}
else
{
System.out.println("ERROR - not a double");
System.exit(0);
}
Car key = new Car(carMake, carYear, carPrice);
// Stores the output of seqSearch in pos.
// If the debug switch is on, then it prints these statements.
if(DEBUG_SW == true)
{
System.out.println("Search, make = " + key.getMake());
System.out.println("Search, year = " + key.getYear());
System.out.println("Search, price = " + key.getPrice());
}
System.out.println("key =");
System.out.println(key);
pos = seqSearch(carArr, count, key);
if(pos != -1)
{
System.out.println("This vehicle was found at index = " + pos);
}
else
{
System.out.println("This vehicle was not found in the database.");
}
}
}
// This method prints the database of cars.
private static void printData(Car[] carArr, int count)
{
for(int i = 0; i < count; i++)
{
System.out.println("Description of car:");
System.out.println(carArr[i]);
}
}
// Searches for a match in the database.
private static int seqSearch(Car[] carArr, int count, Car key)
{
for(int i = 0; i < count; i++)
{
boolean b = key.equals(key, carArr[i]);
if(b == true)
{
return i;
}
}
return -1;
}
// Prints debug statements if DEBUG_SW is set to true.
public static void debugSwitch(Car[] carArr, boolean DEBUG_SW, int count)
{
if(DEBUG_SW == true)
{
for(int i = 0; i < count; i++)
{
System.out.println("DB make = " + carArr[i].getMake());
System.out.println("DB year = " + carArr[i].getYear());
System.out.println("DB price = " + carArr[i].getPrice());
}
}
}
}

I think this is your problem, but I might be wrong:
Inside your while loop, you have these calls:
next()
nextInt()
nextDouble()
The problem is that the last call (nextDouble), will not eat the newline. So to fix this issue, you should add an extra nextLine() call at the end of the two loops.
What happens is that the next time you call next(), it will return the newline, instead of the CarMake-thing.