Thread: how to?

i have to make sure the user presses a number between 0 and a 1000 , but i'm not sure how to do it.
For other cases i used while ( !keuze.equals("1") && !keuze.equals("2") && !keuze.equals("3") ); but that doesn't
work in this case,because i'm not using a string but a Long(and there to much numbers to equal.
If the number is not between 0 or 1000 i want the println"how many simulations do you want" to repeat.

System.out.println("how many simulations do you wanna do(maximaal 1000)");
number of simulations = Input.readLong();


for ( y = 0 ; y < aantalSimulaties ; y ++) {
algoritme();
tellenVanBalletjes();
Any ideas?

do you mean like this
do {
System.out.println("Hoeveel simulaties wil je uitvoeren?(maximaal 1000)");
aantalSimulaties = Input.readInt();

for ( y = 0 ; y < aantalSimulaties ; y ++) {
algoritme();
tellenVanBalletjes();
}
}

while ( aantalSimulaties >= 0 && 1000 >= aantalsimulaties );

And what is the problem in getting Long as input?
Be specific and get specific replies.

else if(keuze.equals("2")) {
keuzes2();
AantalSim();
keuzes2a();
}
public void keuzes 2() {
do {
System.out.println("Hoeveel simulaties wil je uitvoeren?(maximaal 1000)");
aantalSimulaties = Input.readInt();
}
while ( aantalSimulaties >= 0 && 1000 >= aantalSimulaties );

}
public void AantalSim() {
long y;
for ( y = 0 ; y < aantalSimulaties ; y ++) {
algoritme();
tellenVanBalletjes();
}
}

When i pres a number that isn't between 0 and 1000 the do doesn't repeat?

When i pres a number that isn't between 0 and 1000 the do doesn't repeat?

Yeah coz you want while loop to repeat only if it's between 0 and 1000.
Is it a problem? "Sighs"

I've changed it to tis but it still won't work.
public void keuzes2() {

do {
System.out.println("how many simulations do you ant to do(maximaal 1000)");
amountofsim = Input.readInt();
}
while ( aantalSimulaties < 0 && 1000 < aantalSimulaties );

while ( aantalSimulaties < 0 && 1000 < aantalSimulaties );

What value is both < 0 and > 1000?
Would you want to loop back if either is true vs both being true?

you can only give one number at a time.

That's right. You can use the AND test to see if a number is in a range. A number can be both > 10 and < 20.
There is no number that is both < 0 and > 1000.
You want to repeat the loop if the entered number is either < 0 OR > 1000

One more problem now, the loop has to repeat if the number isn't between 0 and 1000, but if the use enters a letter is has to loop aswell. How to do this without including the intire alphabet to the while with OR's

How are you reading the input from the user? What datatype does the readInt() method return?
What happens if the user does not enter a valid number?

do {
System.out.println("Hoeveel simulaties wil je uitvoeren?(minimaal 0,maximaal 1000)");
aantalSimulaties = Input.readInt();
}
while ( aantalSimulaties <= 0 || 1000 <= aantalSimulaties );

errors
Exception in thread "main" java.util.InputMismatchException
at java.util.Scanner.throwFor(Scanner.java:840)
at java.util.Scanner.next(Scanner.java:1461)
at java.util.Scanner.nextInt(Scanner.java:2091)
at java.util.Scanner.nextInt(Scanner.java:2050)
at Input.readInt(Input.java:104)
at Bordvangalton3.keuzes2(Bordvangalton3.java:88)
at Bordvangalton3.keuzes2c(Bordvangalton3.java:123)
at Bordvangalton3.keuzes2a(Bordvangalton3.java:109)
at Bordvangalton3.keuzes2c(Bordvangalton3.java:125)
at Bordvangalton3.keuzes2a(Bordvangalton3.java:109)
at Bordvangalton3.keuzes2c(Bordvangalton3.java:125)
at Bordvangalton3.keuzes2a(Bordvangalton3.java:109)
at Bordvangalton3.keuzes(Bordvangalton3.java:57)
at Bordvangalton3.keuzesWeergeven(Bordvangalton3.java :20)
at Bordvangalton3.main(Bordvangalton3.java:222)

java.util.InputMismatchException

That's what happens when the user enters the wrong data.
You can handle that exception by using try{<your code here>}catch

isn't there a way to repeat the loop so it keeps asking the amount of simulations that is required,the same way i did with the do while.

while ( aantalSimulaties <= 0 || 1000 <= aantalSimulaties || aantalSimulaties ==a || aantalSimulaties ==b ....... );

Because we haven't seen the try catch method and are not allowed to use it.

What is the datatype of the variable that contains the data that you must test? Is it a number like an int or is it a String?
That will determine what kind of conditional tests you can do in the while loop.
If you use the readInt() method then I assume that the datatype is int. If the user enters non-numeric data like "A" then the readInt() method throws an exception like in post#14.
I don't know what you have learned and what you are permitted to use for this program.

i'm using the int type, i have to make sure any enter the users gives, not between 1 or 1000 gives the question again.
Is it a better way to use a string?And how do you compare al the numbers between 1 and 1000 with the string?
aantalsimulaties=inputreadstring
while ( aantalSimulaties <= 0 || 1000 <= !aantalSimulaties );

You have a problem with the input. You can input numbers with readInt() or you can input Strings with another method.
But then you have to test that the String is a valid number before you can convert it to a number. You won't be able to do a numeric test with a String.
I don't know if you know how to do test for a valid numeric String yet.
Do you know how to convert a numeric String to an int?

int i = Integer.parseInt(s);??

Originally Posted by robingeldolf

int i = Integer.parseInt(s);??

Did you try this?
Don't ask us but test it in your application and if got any errors, ask here.

But i don't know what to do if i converted the string

i don't know what to do if i converted the string

You must have a use for the data in the String or you would not have asked the user to enter it.
Please explain what the data in the String is used for? Why does your program get that data?

the data in the string is used to create an amount of simulations. If the string is 100 the simulation has to run 100 times. But i want to make sure the users gives a number that is between 0 and 1000, so no letters to.

If the user enters a String, what methods are you allowed to use to determine if that String is all numeric digits or if it contains letters?
One way is to use try{} catch block with an Integer class parse method that throws an exception if the String is not a valid number.
Once you have converted the String to an int then you can test if its value is in the desired range.