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Why is my code is outputing thousands of times?

I am supposed to make this code output Day total and then the number of hours worked for that day. The code is currently displaying the day and the total. But it is displaying too many times for the program to even register. For instance, it asks to input a day, and I'll put in Monday. Then the number of hours worked, and I'll put 6. It will then output Monday 6.0 thousands of times. The expected output should be Day Total 6. What am I missing or is added to cause this?
// SuperMarket.java - This program creates a report that lists weekly hours worked
// by employees of a supermarket. The report lists total hours for
// each day of one week.
// Input: Interactive
// Output: Report.
import java.util.Scanner;
public class SuperMarket
{
public static void main(String args[])
{
// Declare variables.
final String HEAD1 = "WEEKLY HOURS WORKED";
final String DAY_FOOTER = " Day Total "; // Leading spaces are intentional.
final String SENTINEL = "done"; // Named constant for sentinel value.
double hoursWorked = 0; // Current record hours.
String hoursWorkedString = ""; // String version of hours
String dayOfWeek; // Current record day of week.
double hoursTotal = 0; // Hours total for a day.
String prevDay = ""; // Previous day of week.
boolean done = false; // loop control
Scanner input = new Scanner(System.in);
// Print two blank lines.
System.out.println();
System.out.println();
// Print heading.
System.out.println(HEAD1);
// Print two blank lines.
System.out.println();
System.out.println();
// Read first record
System.out.println("Enter day of week or done to quit: ");
dayOfWeek = input.nextLine();
if(dayOfWeek.compareTo(SENTINEL) == 0)
done = true;
else
{
System.out.print("Enter hours worked: ");
hoursWorkedString = input.nextLine();
hoursWorked = Integer.parseInt(hoursWorkedString);
prevDay = dayOfWeek;
}
while(done == false)
{
System.out.println(dayOfWeek + " " + hoursWorked);
hoursTotal = 0;
prevDay = hoursWorkedString;
}
System.out.println(dayOfWeek + " " + hoursWorked + hoursTotal);
hoursTotal++;
if(dayOfWeek.compareTo(SENTINEL) == 0)
{
hoursWorked = dayOfWeek.compareTo(SENTINEL);
prevDay = dayOfWeek;
done = true;
}
else
done = false;
// Include work done in the dayChange() method
if(dayOfWeek.compareTo(SENTINEL) == 0)
System.out.println(DAY_FOOTER + hoursTotal);
System.exit(0);
} // End of main() method.
} // End of SuperMarket class.

while(done == false)
{
System.out.println(dayOfWeek + " " + hoursWorked);
hoursTotal = 0;
prevDay = hoursWorkedString;
}
In this code block, you aren't changing done variable, so it is an infinite loop.

Reverse integer including 0's in java

I have to do a program that returns the reverse of a number that is input by a user, event the numbers that start and finish with 0 (ex. 00040, it would print 04000)
I was able to do the reverse of the number, but it doesn't print out the 0's and I can't use String variables, just long variables or integers.
Here is my code:
import java.util.Scanner;
public class Assignment_2_Question_2 {
public static void main(String[] args) {
Scanner keyboard = new Scanner (System.in);
System.out.println("Welcome to Our Reversing Number Program");
System.out.println("-----------------------------------------");
System.out.println();
System.out.println("Enter a number with at most 10 digits:");
long number = keyboard.nextInt();
long nbDigits = String.valueOf(number).length();
System.out.println("Number of digits is " + nbDigits);
System.out.print("Reverse of " + number + " is ");
long revNumber = 0;
while (number > 0){
long digit = number % 10;
if (digit == 0){ // The teacher told me to add this
nb0 ++; // need to not take into account the 0's inside the number
}
revNumber = revNumber * 10 + digit;
number = number/10;
}
for (int i = 0; i < nb0; i++) { // This will print the number of 0's counted by the if statement and print them out.
System.out.println("0");
}
System.out.println(revNumber);
String answer;
do{
System.out.println("Do you want to try another number? (yes to repeat, no to stop)");
answer = keyboard.next();
if (answer.equalsIgnoreCase("yes")){
System.out.println("Enter a number with at most 10 digits:");
long otherNumber = keyboard.nextInt();
long nbrDigits = String.valueOf(otherNumber).length();
System.out.println("Number of digits is " + nbrDigits);
System.out.print("Reverse of " + otherNumber + " is ");
long reversedNumber = 0;
while (otherNumber != 0){
reversedNumber = reversedNumber * 10 + otherNumber%10;
otherNumber = otherNumber/10;
}
System.out.println(reversedNumber);
}
else
System.out.println("Thanks and have a great day!");
}while(answer.equalsIgnoreCase("yes")&& !answer.equalsIgnoreCase("no"));
}
}
Can someone help me? Thank you

Probably not what is intended but clearly (based on problem statement) you must see all digits entered (to include leading 0's) otherwise it is an "impossible solution" - and you state you cannot receive input as a String...
So this snippet reads one digit at a time where each digit is received as an int:
Scanner reader = new Scanner(System.in);
reader.useDelimiter(""); // empty string
System.out.print("Enter number: ");
while (!reader.hasNextInt()) reader.next();
int aDigit;
int cnt = 0;
while (reader.hasNextInt()) {
aDigit = reader.nextInt();
System.out.println("digit("+ ++cnt + ") "+aDigit);
}
System.out.println("Done");
Prints (assume user enter 012 (enter)):
Enter number: digit(1) 0
digit(2) 1
digit(3) 2
Done
You naturally have more work to do with this but at least you have all user entered digits (including leading zeros).

You can use buffer reader;
Like this given code And if you want to do some arithmetic operations in the numbers then you can convert it into int using parseInt method.:-
import java.util.Scanner;
import java.lang.*;
class Main {
public static void main(String args[])
{
System.out.println("ENTER NUM");
Scanner SC = new Scanner(System.in);
String INP = SC.nextLine();
StringBuffer SB = new StringBuffer(INP);
SB.reverse() ;
System.out.println(SB);
}
}

How to split a string up and save it to a variable if it is valid?

I'm having some problems splitting a string that is read in from an input file, making sure it's valid, then saving it to a variable.
Let's say this is the first string:
12345 5 59.28
I would want to split the 12345, 5, and 59.28.
After verifying that they are the correct format ( 00000-99999, 0-5, 000.00 0 100.00 ), I would then assign it to a variable.
My main two obstacles are that I CANNOT use arrays in this program, so I'm not sure how to split the string. I have tried just pulling each section as an int, but that doesn't seem to work.
My other problem is that I'm not sure how to validate it. Would I be using something like this:
//Assuming I have a scanner set up and a class, method declared
//Declare variables
int numbers;
int studentID;
while(fileInput.hasNext())
{
numbers = fileInput.nextInt(); //Not sure how to pull a part of the string
}
//Used to validate that it is within the range
if(numbers < 00000 || numbers > 99999)
{
studentID = numbers;
}
I am a beginner at Java so please do excuse my confusion.

If you know what the structure of the file is, for example if it's always formatted like this:
int int double
Then you can simply callnextInt(), nextInt(), and then nextDouble() to parse the data from it that way.
Maybe something like this
do
{
num1 = scanner.nextInt();
num2 = scanner.nextInt();
num3 = scanner.nextDouble();
} while (scanner.hasNextInt());
And do that in order to collect all of your data, but you'll likely need lots of variables if you have any substantial amount of data you're reading in
Or if there's bad data sometimes with it's correct data immediately after it you could so something like this to skip over the bad one, even though it's not very pretty
do
{
if (scanner.hasNextInt())
{
num1 = scanner.nextInt();
}
else
{
scanner.next() // move past whatever bad data there was
num1 = scanner.nextInt();
}
if (scanner.hasNextInt())
{
num2 = scanner.nextInt();
}
else
{
scanner.next() // move past whatever bad data there was
num2 = scanner.nextInt();
}
if (scanner.hasNextDouble())
{
num3 = scanner.nextDouble();
}
else
{
scanner.next() // move past whatever bad data there was
num3 = scanner.nextDouble();
}
} while (scanner.hasNext());

I think your teachers give this assignment to practice your if-else condition or switch statement and for loop(fundamental) skills.
Here what I did, this may be not completely match with your assignment question but using this you can get complete idea and think of a way to reduce this. Hey! because of we are not here to do your assignment. you have to tackle with your problem and get familiar with those.
Try to understand these, do changes look what happen:
public static void main(String[] args) {
Scanner fileInput = new Scanner(System.in);
//Declare variables
String numbers = "";
String firstNum = "";
String secondNum = "";
String thirdNum = "";
int studentID = 0;
int secondDigit = 0;
double thirdDigit = 0;
System.out.print("Input: ");
numbers = fileInput.nextLine();
int firstIndex = 0;
int secondIndex = 0;
int thirdIndex = 0;
firstIndex = numbers.indexOf(" ");
if(firstIndex <= 4){
System.out.println("Number should be 5");
}else{
firstNum = numbers.substring(0, firstIndex);
numbers = numbers.substring(firstIndex+1);
studentID = Integer.parseInt(firstNum);
if(studentID > 0 && studentID < 99999){
System.out.println("First num: " +firstNum);
}else{
System.out.println("first digits not in a range ");
}
}
secondIndex = numbers.indexOf(" ");
if(secondIndex == 0){
System.out.println("no number");
}else{
secondNum = numbers.substring(0, secondIndex);
numbers = numbers.substring(secondIndex+1);
secondDigit = Integer.parseInt(secondNum);
if(secondDigit >= 0 && secondDigit <= 5){
System.out.println("Second num: " +secondNum);
}else{
System.out.println("second digit not in a range ");
}
}
thirdIndex = numbers.length();
if(thirdIndex < 3){
System.out.println("3 numbers should be there");
}else{
thirdNum = numbers.substring(0, thirdIndex);
thirdDigit = Double.parseDouble(thirdNum);
if(thirdDigit >= 0 && thirdDigit <= 100){
System.out.println("third num: " +thirdNum);
}else{
System.out.println("third digit not in a range ");
}
}
}
I'm not going to explain this also. You have to try, if you have any problem after tackling with this code. ask any question in comment.
Hope this will help!

Try this. Invalid formats will throw an exception during the next method call.
import java.util.Scanner;
class Main {
public static void main(String[] args) {
Scanner in = new Scanner("12345 5 59.28");
in.useDelimiter(" "); // reads per space
String next = in.next("\\d{5}"); // reads next 5 digits
int numbers = Integer.valueOf(next);
System.out.println(numbers);
next = in.next("\\d{1}"); // reads next 1 digit
int studentId = Integer.valueOf(next);
System.out.println(studentId);
next = in.next("\\d{2}\\.\\d{2}"); // reads next a decimal with two digits before and after point
float floatingNumbers = Float.valueOf(next);
System.out.println(floatingNumbers);
}
}
<script src="//repl.it/embed/IWzC/0.js"></script>

Validate multiple inputs to an array in java

I have a HOMEWORK assignment that involves users inputs.
I want to ask the user for three integer inputs in the range 1-7 and store them in an array.
What I have so far seems to validate properly if all inputs are over 7 and rules out strings etc inputs and but still allows for a single input to be over 7.
Any help is appreciated.
Scanner in = new Scanner(System.in);
boolean valid = false;
int[] inputRange = new int[3];
while(!valid)
{
System.out.println("enter three numbers: ");
if(in.hasNextInt())
{
for(int i = 0; i< inputRange.length; i++)
{
inputRange[i] = in.nextInt();
if(inputRange[i] >= 1 && inputRange[i] <= 9){
valid = true;
}
}
}else{
in.next();
}
}

Your logic is fine, but you need to restart valid to false again each time user is going to enter a new digit.
Here's how you can validate user input to be between 1-9 with a do-while using your same logic just a little bit different.
Also next time be sure to post a valid MCVE and not just "snippets" (it should include a main method and imports)
import java.util.Scanner;
public class ValidationOfNumbers {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
boolean valid = false;
int[] inputRange = new int[3];
int counter = 0;
int number = 0;
System.out.println("Enter 3 digits between 1-9"); //Ask for digits, numbers can have multiple digits, while digits are numbers from 0-9
for (int i = 0; i < inputRange.length; i++) {
valid = false; //Restart "valid" variable for each new user input
do {
number = in.nextInt();
if (number >= 1 && number <= 9) {
valid = true; //If valid, it will exit do-while
} else {
System.out.println("Enter a valid digit between 1-9");
}
} while (!valid);
inputRange[i] = number; //We know it's valid because it went out of do-while, so we can now store it in the array
}
for (int i = 0; i < inputRange.length; i++) {
System.out.println(inputRange[i]);
}
}
}

Here is the code
Scanner in = new Scanner(System.in);
int count = 0;
int data[] = new int[3];
while(count < 3) {
if(in.hasNextInt()) {
int val = in.nextInt();
if(val>=1 && val <=7) {
data[count] = val;
count++;
}
}
else {
in.next();
}
}

This while loop doesn't seem to loop - there is only math in the loop

I can not figure out why my loop won't continue. Every time I run the program, it executes only one iteration of the loop.
I am implementing the algorithm based on mathematician Lewis Caroll where you remove the last digit from an input number and subtract it from the number formed by the remaining digits. For example, if I input the number 48070 the output is
48070
4807
and it stops there instead of continuing.
// The "Divisible_Dianik" class.
import java.awt.*;
public class Divisible_Dianik
{
public static void main (String[] args)
{
int userinput = 1;
int lastint;
int firstpart;
int output = 1;
while (output != 0)
{
userinput = In.getInt ();
lastint = userinput % 10;
firstpart = userinput / 10;
output = firstpart - lastint;
System.out.println (output);
userinput = output;
}
} // main method
} // Divisible_Dianik class

I'm going to assume that In.getInt() is some kind of abstraction for getting terminal-based feedback from the user. It's easily supplanted by this:
Scanner scan = new Scanner(System.in);
// in the loop
userinput = scan.nextInt();
scan.nextLine();
If this is the case, the reason you don't loop is due to this blocking for input every time. What you want to do is move the request for input outside of the loop.
int lastint;
int firstpart;
int output = 1;
Scanner scan = new Scanner(System.in);
int userinput = scan.nextInt();
while (output != 0) {
lastint = userinput % 10;
firstpart = userinput / 10;
output = firstpart - lastint;
System.out.println(output);
userinput = output;
}