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Simple method for taking in an int, checking if it falls in a min/max, and returning that value.. not able to break out of method

I'm fairly new to java and I'm trying to make a simple method in a class that returns a user integer as long as it falls within certain boundaries. It seems to check the input correctly, but after that, it doesn't exit the method. Here is the method:
public int readInt(String prompt, int min, int max) {
int userInt;
boolean works = true;
System.out.println(prompt);
userInt = inputReader.nextInt();
inputReader.nextLine();
while(works = true) {
if (userInt >= min && userInt <= max) {
works = false;
} else {
System.out.println("Please enter value between " + min + " and " + max);
userInt = inputReader.nextInt();
inputReader.nextLine();
}
}
return userInt;
}
And here is the main method. Running the method and just trying to print the int back out after. Never gets to the sout line.
public static void main(String[] args) {
UserIO userIO = new UserIOImpl();
int userInt;
userInt = userIO.readInt("Please enter a number between 1 and 10", 1, 10);
System.out.println(userInt);
}
Any help in the right direction is greatly appreciated.
Edit: I'm currently using NetBeans 12.0

Instead of "while(works = true)" make "while(works)"

Method not being called properly?! Calorie App [closed]

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Closed 2 years ago.
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package com.company;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
//making values easier to change and also create global variables for gym comparison
Scanner scan = new Scanner (System.in);
System.out.println("How many calories did you consume today?>> ");
int actualIntake = scan.nextInt();
System.out.println("What is your BMR?>> ");
int BMR = scan.nextInt();
scan.close();
//this method is what is expected with deficit
calorieCalculation(actualIntake,BMR);
//this is what you actually ate
actualCalories(actualIntake,BMR);
//gym with protein
gym (30,40,50,100, actualIntake);
}
//testing method
testingMeth(actualIntake);
//What the user should be following
public static int calorieCalculation(int actualIntake, int BMR){
int calorieDifference = BMR - actualIntake;
if (calorieDifference <= 0 ){
calorieDifference = Math.abs (BMR - actualIntake);
System.out.println("You have went over your deficit, well done fatty = " + calorieDifference);
} else if (calorieDifference >= 0){
System.out.println("Expected calorie deficit should be " + calorieDifference);
}
return calorieDifference;
}
//What the user actually did
public static int actualCalories (int actualIntake, int BMR ) {
int deficitCalculation = actualIntake - BMR;
if (actualIntake > BMR ) {
System.out.println("You fat lard stop overeating you dumbass, " + "failed deficit of over " + deficitCalculation + " Calories.");
} else if (actualIntake < BMR ) {
System.out.println("Well done you created a deficit of " + deficitCalculation + " keep her going keep her movin." );
}
return deficitCalculation;
}
//How much did you burn in the gym
public static int gym (int treadMillCal, int rowingMachineCal, int weightsCal, int proteinShakeCal, int actualIntake) {
int totalGym = ((treadMillCal + rowingMachineCal + weightsCal) - proteinShakeCal);
if (totalGym >= 50 ) {
System.out.println("Well done you have burned more than 50 calories whilst drinking protein shake");
} else if (totalGym < 50 ) {
System.out.println("Whats the bloody point of drinking protein if your putting the calories back on fatty: " + totalGym + " calories is how much you lost");
}
int gymAndTotal = actualIntake - totalGym;
System.out.println("What you ate, plus minusing your workout along with the protein you consumed " + gymAndTotal);
return totalGym;
}
public static void testingMeth (int actualIntake) {
System.out.println(actualIntake);
}
}
//Take calories in then calculate BMR and compare, return value
So I am currently learning java, just learning and making random calorie deficit and BMR program. I created a new method called:
public static int testingMeth(actualIntake) {
System.out.println(actualIntake);
}
The issue is when i try to call the method after the gym method, it creates an error.
gym (30,40,50,100, actualIntake);
}
testingMeth(actualIntake);
If i was to delete the gym method from the main method, all my other methods has errors. I do not necessarily need a solution for this program but rather why am i receiving these errors? Just want to learn and improve! Thanks.
In other words, I can call the testingMeth before the Gym method and it works fine, but why not after the gym method? and if i get rid of the gym method, multiple errors occur amongst the other methods within the program?

If you see below code, i am able to run both method in any sequence and it's working fine as well.
You need to go through with basics of method declaration and method call.
It will help you.
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
//making values easier to change and also create global variables for gym comparison
Scanner scan = new Scanner(System.in);
System.out.println("How many calories did you consume today?>> ");
int actualIntake = scan.nextInt();
System.out.println("What is your BMR?>> ");
int BMR = scan.nextInt();
scan.close();
//this method is what is expected with deficit
calorieCalculation(actualIntake, BMR);
//this is what you actually ate
testingMeth(actualIntake);
actualCalories(actualIntake, BMR);
//gym with protein
gym(30, 40, 50, 100, actualIntake);
}
//testing method
//What the user should be following
public static int calorieCalculation(int actualIntake, int BMR) {
int calorieDifference = BMR - actualIntake;
if (calorieDifference <= 0) {
calorieDifference = Math.abs(BMR - actualIntake);
System.out.println("You have went over your deficit, well done fatty = " + calorieDifference);
} else if (calorieDifference >= 0) {
System.out.println("Expected calorie deficit should be " + calorieDifference);
}
return calorieDifference;
}
//What the user actually did
public static int actualCalories(int actualIntake, int BMR) {
int deficitCalculation = actualIntake - BMR;
if (actualIntake > BMR) {
System.out.println("You fat lard stop overeating you dumbass, " + "failed deficit of over " + deficitCalculation + " Calories.");
} else if (actualIntake < BMR) {
System.out.println("Well done you created a deficit of " + deficitCalculation + " keep her going keep her movin.");
}
return deficitCalculation;
}
//How much did you burn in the gym
public static int gym(int treadMillCal, int rowingMachineCal, int weightsCal, int proteinShakeCal, int actualIntake) {
int totalGym = ((treadMillCal + rowingMachineCal + weightsCal) - proteinShakeCal);
if (totalGym >= 50) {
System.out.println("Well done you have burned more than 50 calories whilst drinking protein shake");
} else if (totalGym < 50) {
System.out.println("Whats the bloody point of drinking protein if your putting the calories back on fatty: " + totalGym + " calories is how much you lost");
}
int gymAndTotal = actualIntake - totalGym;
System.out.println("What you ate, plus minusing your workout along with the protein you consumed " + gymAndTotal);
return totalGym;
}
public static void testingMeth(int actualIntake) {
System.out.println(actualIntake);
}
}
You need to understand for every opening braces of class/method/switch-case/or condition must have closing braces.
In your case you are try to call some method after closing braces of class, so those elements are not part of your class and that's why it's throwing an error.

Output will not print the correct information

I'm trying to make a program which asks the user a particular bird then how many of them they had seen at that point. If the use at any point enters the word 'END' then the system should print out the most seen bird and the number seen. However, when running my program if I enter 'END' at random points it instead returns that the most seen was END with 0 seen. I can't figure out how to make it work. I've tried different methods but it's just not working properly. Also, I've set the maximum array limit to 10 possitions but it continues after 10 and if i enter a value the system crashes. Have I written the limit part properly? Or am I missing something important?
import java.util.Scanner;
public class testing
{
public static void main (String[] param)
{
birdInput();
most();
System.exit(0);
}
public static void birdInput()
{
int i = 0;
String birdInput;
int numberInput;
Scanner scanner = new Scanner(System.in);
int maxVal = Integer.MIN_VALUE;
int maxValIndex = -1;
while (true)
{
System.out.println("What bird did you see?");
birdInput = scanner.nextLine();
if (birdInput.equals("END"))
{
System.out.print("\nWell....I guess thanks for using this program?\n");
System.exit(0);
}
else
{
String[] birds = new String[10];
int[] numbers = new int[10];
birds[i] = scanner.nextLine();
System.out.println("How many did you see?");
numbers[i] = scanner.nextInt();
i++;
if (birds[i].equals("END"))
{
maxVal = numbers[i];
maxValIndex = i;
System.out.print("\nThe most common bird that you saw was the " + birds[maxValIndex] + " with " + maxVal + " being seen in total\n");
System.exit(0);
}
}
}
}
public static void most()
{
System.out.println("fdff");
}
}
This is my edit of Till Hemmerich's answer to my issue. I tried to remove the global variables and so combine the entire code into 1 method. However, I'm still having some issues. Been working at it but really confused.
import java.util.Scanner;
public class birds2
{
public static void main(String[] param)
{
birdInput();
System.exit(0);
}
public static void birdInput()
{
Scanner scanner = new Scanner(System.in);
String[] birds = new String[99999999];
int[] numbers = new int[99999999];
int i = 0;
int maxIndex;
while (i <= birds.length)
{
System.out.println("What bird did you see?");
birds[i] = scanner.nextLine();
System.out.println("How many did you see?");
numbers[i] = scanner.nextInt();
i++;
}
int newnumber = numbers[i];
if ((newnumber > numbers.length))
{
maxIndex = i;
i++;
}
if (birds[i].toUpperCase().equals("END"))
{
System.out.print("\nWell....I guess thanks for using this program?\n");
System.out.print("\nThe most common bird that you saw was the " + birds[maxIndex] + " with " + numbers[maxIndex] + " being seen in total\n");
System.exit(0);
}
}
}

You're re-declaring the birds and numbers arrays in each iteration of the loop. They should be declared and initialized only once, before the loop.

I changed a lot so im going to explain my changes here in total.
First of all i had to move the Array Definition out of your while-loop as >mentioned above, since other wise you would override these Arrays every time.
I also made them globally accessible to work with them in other methods.
public static int maxIndex;
public static String[] birds = new String[10];
public static int[] numbers = new int[10];
in general I re structured the whole code a little bit to make it more readable and a little bit more object-orientated.
For example I created an method called inputCheck() which returns our input as a String and check if it equals END so you do not have to write your logic for this twice. (it also considers writing end lower or Uppercased by just Upper our input before checking it"if (input.toUpperCase().equals("END"))")
static String inputCheck() {
Scanner scanner = new Scanner(System.in);
String input = scanner.nextLine();
if (input.toUpperCase().equals("END")) {
end();
}
return input;
}
this method can now be called every time you need an input like this:
birds[i] = inputCheck();
but you need to be carefull if you want to get an integer out of it you first have to parse it like this:Integer.parseInt(inputCheck())
after that I wrote a method to search for the biggest Value in your numbers Array and getting its index:
public static int getMaxIndex(int[] numbers) {
for (int i = 0; i < numbers.length; i++) {
int newnumber = numbers[i];
if ((newnumber > numbers.length)) {
maxIndex = i;
}
}
return maxIndex;
}
it takes an int array as parameter and returns the index of the highest element in there as an Integer. Called like this:maxIndex = getMaxIndex(numbers);
Then after that I rewrote your end method. It now just calles our getMaxIndex method and prints some output to the console.
public static void end() {
maxIndex = getMaxIndex(numbers);
System.out.print("\nWell....I guess thanks for using this program?\n");
System.out.print("\nThe most common bird that you saw was the " + birds[maxIndex] + " with " + numbers[maxIndex] + " being seen in total\n");
System.exit(0);
}
to fix your last problem (crashing after more then 10 inputs)I changed your while-loop. Since your array only has 10 places to put things it crashes if you try to put information in place number 11. it not looks like this:while (i <= birds.length) instead of while (true) this way the max loops it can take is the amout of places Array birds has and it wont crash anymore.
public static void birdInput() {
int i = 0;
while (i <= birds.length) {
System.out.println("What bird did you see?");
birds[i] = inputCheck();
System.out.println("How many did you see?");
numbers[i] = Integer.parseInt(inputCheck()); //you should check here if its actuall a number otherwiese your programm will crash
i++;
}
}
Here is the whole code in total:
import java.util.Scanner;
/**
*
* #author E0268617
*/
public class JavaApplication1 {
public static int maxIndex;
public static String[] birds = new String[10];
public static int[] numbers = new int[10];
public static void main(String[] param) {
birdInput();
most();
System.exit(0);
}
public static void birdInput() {
int i = 0;
while (i <= birds.length) {
System.out.println("What bird did you see?");
birds[i] = inputCheck();
System.out.println("How many did you see?");
numbers[i] = Integer.parseInt(inputCheck()); //you should check here if its actuall a number otherwiese your programm will crash
i++;
}
}
static String inputCheck() {
Scanner scanner = new Scanner(System.in);
String input = scanner.nextLine();
if (input.toUpperCase().equals("END")) {
end();
}
return input;
}
public static int getMaxIndex(int[] numbers) {
for (int i = 0; i < numbers.length; i++) {
int newnumber = numbers[i];
if ((newnumber > numbers.length)) {
maxIndex = i;
}
}
return maxIndex;
}
public static void end() {
maxIndex = getMaxIndex(numbers);
System.out.print("\nWell....I guess thanks for using this program?\n");
System.out.print("\nThe most common bird that you saw was the " + birds[maxIndex] + " with " + numbers[maxIndex] + " being seen in total\n");
System.exit(0);
}
public static void most() {
System.out.println("fdff");
}
}
I hope you understand where the Problems had been hidden if you have any Questions hit me up.

Java / Creating hi/low game using multiple methods, stuck at returning no. of guesses

I'm creating a high/low guessing game as part of a study assignment, and the part im stuck at is getting the amount of guesses returned to the main method. We have specifically been told that the main method has to print the number of guesses, while the method "playGame" actually does the playing.
There's more to the code, a method called giveReponse that checks if the number is correct or too high/low, but it works as intended. I get "Cannot find symbol" when trying to print how many guesses it took to complete the game.
If it wasn't so important to print it in the main method I'd print the amount in the method playGame, but thats a no-go. What am I doing wrong?
The code looks like this:
public class HiLo {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("Welcome to classic guessing game of high/low!");
String difficulty = scan.next();
if (difficulty.equals("easy")) {
playGame(10);
} else if (difficulty.equals("medium")) {
playGame(100);
} else if (difficulty.equals("hard")) {
playGame(1000);
}
System.out.println("You won in" + guesses + "attempts.");
}//EndsMain
public static int playGame(int maxNumber) {
Scanner scan = new Scanner(System.in);
int rannr = (int)(Math.random() * maxNumber) +1;
int answer = rannr;
int guess = 0;
int guesses = 0;
System.out.println("Game is starting...");
do {
guess = scan.nextInt();
guesses ++;
giveResponse(answer, guess);
if (answer == guess) {
break;
}
} while (answer != guess);
return guesses;
} //Ends playGame

Your method playGame( ) is returning a value but since is not assigned to no variable, those returns are getting lost...
additional to that it looks like the code is not complete:
this statement is not going to let you compile:
System.out.println("You won in" + guesses + "attempts.");
because the only guesses variable I see in there is scoped in the playGame method....
do instead something like:
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("Welcome to classic guessing game of high/low!");
int guesses = 0;
String difficulty = scan.next();
if (difficulty.equals("easy")) {
guesses = playGame(10);
} else if (difficulty.equals("medium")) {
guesses = playGame(100);
} else if (difficulty.equals("hard")) {
guesses = playGame(1000);
}

The problem is at:
System.out.println("You won in" + guesses + "attempts.");
Since the variable guesses is not defined in the main method, the compiler doesn't know what you are referencing to with that symbol.
But since playGame() returns the number of guesses, I'd recommend something like this:
if (difficulty.equals("easy")) {
System.out.println("You won in" +playGame(10)+ "attempts.");
} else if (difficulty.equals("medium")) {
System.out.println("You won in" +playGame(100)+ "attempts.");
} else if (difficulty.equals("hard")) {
System.out.println("You won in" +playGame(1000)+ "attempts.");
}

Here's a solution that shows how easy it would be to restrict guesses. Not much extra effort or thought:
package games;
import java.util.Random;
import java.util.Scanner;
/**
* HiLo guessing game
* Created by Michael
* Creation date 4/9/2016.
* #link https://stackoverflow.com/questions/36522303/java-creating-hi-low-game-using-multiple-methods-stuck-at-returning-no-of-gu
*/
public class HiLo {
public static void main(String [] args) {
int maxValue = (args.length > 0) ? Integer.parseInt(args[0]) : 100;
int maxGuesses = (args.length > 1) ? Integer.parseInt(args[1]) : 5;
Scanner scanner = new Scanner(System.in);
String answer = "Y";
do {
play(scanner, maxValue, maxGuesses);
System.out.println("Play again? [Y/N]: ");
answer = scanner.next();
System.out.println(String.format("You answered %s; let's play again!", answer));
} while ("Y".equalsIgnoreCase(answer));
}
private static void play(Scanner scanner, int maxValue, int maxGuesses) {
int value = new Random().nextInt(maxValue) + 1;
int numGuesses = 0;
boolean match = false;
do {
System.out.println(String.format("Guess a value between 1 and %d: ", maxValue));
int guess = Integer.parseInt(scanner.next());
if (guess < value) {
System.out.println(String.format("Too low; guess again. (%d guesses left)", (maxGuesses-numGuesses-1)));
} else if (guess > value) {
System.out.println(String.format("Too high; guess again (%d guesses left)", (maxGuesses-numGuesses-1)));
} else {
match = true;
System.out.println(String.format("You got it right in %d guesses! ", numGuesses+1));
break;
}
} while (!match && ++numGuesses < maxGuesses);
if (!match) {
System.out.println(String.format("The correct answer was %d; you're only allowed %d guesses. Better luck next time!", value, maxGuesses));
}
}
}

Cows and Bulls game

I'm working on a cows and bulls game with two different classes:
The first class looks like this:
import java.util.*;
import java.util.Scanner;
public class CowsAndBulls {
int UserNumber=0;
int CompNumber=0;
int bulls=0;
int cows=0;
Scanner input = new Scanner(System.in);
public void getUserNumber() {
System.out.println("Please enter your guess!");
int UserValue=input.nextInt();
UserNumber=UserNumber+ UserValue;
System.out.println("Your guess is : " + UserNumber);
}
public void getCompNumber() {
Random generator= new Random();
int pickedNumber=generator.nextInt(10000) + 1000;
CompNumber =CompNumber+ pickedNumber;
System.out.println("The computer has guessed : " + CompNumber );
}
}
It just generates a random number for the computer and asks the user to input their guess.
I'm having a lot of trouble with my play class, specifically, I can't get my while loop to run,
public class CowsAndBullsPlay {
public void play() {
int GuessCount=0;
int UserNumber = 0;
int CompNumber = 0;
int cows = 0;
int bullcount=0;
int cowcount=0;
int bulls = 0;
Boolean GameEnds;
GameEnds=false;
while (GameEnds=false) {
CowsAndBulls user= new CowsAndBulls();
user.getUserNumber();
CowsAndBulls comp= new CowsAndBulls();
comp.getCompNumber();
String UserString=String.valueOf(UserNumber);
String CompString=String.valueOf(CompNumber);
String U=UserString;
String C=CompString;
for (int i=0; i<4; i++)
for (int k=i+1; k<4; k++) {
if(U.charAt(i)==C.charAt(k)) {
bullcount ++;
bulls=bulls + bullcount;
}
else if(U.contains(C.charAt(i) + U)) {
//for (int v=0; v<4; v++)
//for (int j=0; j<4; j++) {
cowcount ++;
cows=cows + cowcount;
}
GuessCount++;
}
if (bulls==4) {
GameEnds= true;
System.out.println("Congratulations!");
System.out.println("it took you:" + GuessCount);
}
else {
System.out.println("cows: " + cows);
System.out.println("Bulls:" + bulls);
}
}
}
}
It's supposed to check for cows and then check for bulls, then if bulls is not equal to four, the loop should reiterate--calling the first two methods that ask for user input and ask computer to randomly generate a number and then guesscount should keep track of loop iterations.
The code compiles, but it just won't run the while loop
here is my tester class:
public class CowsAndBullsTester {
public static void main(String[] args) {
int bears = 0;
int cows = 0;
Boolean GameEnds = false;
System.out.println("welcome to Cows Versus Bulls death match!");
CowsAndBulls user= new CowsAndBulls ();
user.getUserNumber();
System.out.println("Now the computer will pick a number!");
CowsAndBulls comp= new CowsAndBulls ();
comp.getCompNumber();
System.out.println("Let's see how you did!");
CowsAndBullsPlay game= new CowsAndBullsPlay();
game.play();
}
}
Really appreciate any help. I'm sure there's some stupid mistake, I'm just not sure what. This is only my third assignment and I'm having some trouble figuring out what's wrong on my own :)
thanks!

You need to change while (GameEnds=false) to while (GameEnds==false).
The first is an assignment, while the second is a comparison. So in the first, false will be assigned to GameEnds, and then GameEnds will evaluate to false for your while condition, meaning that the loop will never enter.
Also, see #AndrewMao's comment below. Generally, you will see booleans used in conditions directly, with or without negation (!), because they already hold truth values and a further comparison is redundant.
Small side note: you may want to rename your variable in camelCase for clarity.