How to avoid this problem?

[kinghippo423]

I have an object receiving a short in argument. This argument is a code for a product and I want this number to be only between 1 and 1000.

If I do this:

Class a = new Class((short)965);
System.out.println(a.getArgument());

This will return 965 as supposed

Class a = new Class((short)1200);
System.out.println(a.getArgument());

This will cause my exception to pop and tell the user to use a code between 1 and 1000. Until here everything is fine. Now comes my problem:

Class a = new Class((short)66000);
System.out.println(a.getArgument());

This will return 464. I want my exception to pop here too. I want to keep my short typevbecause it is useless to take 32 bytes for only a number in the 4 digits mamxium.

How to solve this? For reference, this is my Class. Sorry it's in French but you will be able to understand easily my code don't worry !

Thanks a lot

package TP1;

public class Article
{
public static void main(String[] args)
{
Article a = new Article((short)66000,"Pen",(float)23.45);
System.out.println(a.getNumeroArticle());
}

private short numeroArticle;
private String descriptionArticle;
private float prixArticle;

public Article(short pNumeroArticle, String pDescriptionArticle, float pPrixArticle)
{
setNumeroArticle(pNumeroArticle);
setDescriptionArticle(pDescriptionArticle);
setPrixArticle(pPrixArticle);
}

public short getNumeroArticle()
{
return numeroArticle;
}

public String getDescriptionArticle()
{
return descriptionArticle;
}

public float getPrixArticle()
{
return prixArticle;
}

public void setNumeroArticle(short pNumeroArticle)
{
if(pNumeroArticle > 1000 || pNumeroArticle <= 0)
throw new IllegalArgumentException("Le numéro de l'article doit être compris entre 1 et 1000");
else
numeroArticle = pNumeroArticle;
}

public void setDescriptionArticle(String pDescriptionArticle)
{
descriptionArticle = pDescriptionArticle;
}

public void setPrixArticle(float pPrixArticle)
{
prixArticle = pPrixArticle;
}
}

[madhoriya22]

I have an object receiving a short in argument. This argument is a code for a product and I want this number to be only between 1 and 1000.

If I do this:

Class a = new Class((short)965);
System.out.println(a.getArgument());

This will return 965 as supposed

Class a = new Class((short)1200);
System.out.println(a.getArgument());

This will cause my exception to pop and tell the user to use a code between 1 and 1000. Until here everything is fine. Now comes my problem:

Class a = new Class((short)66000);
System.out.println(a.getArgument());

This will return 464. I want my exception to pop here too. I want to keep my short typevbecause it is useless to take 32 bytes for only a number in the 4 digits mamxium.

How to solve this? For reference, this is my Class. Sorry it's in French but you will be able to understand easily my code don't worry !

Thanks a lot

package TP1;
 
public class Article 
{
public static void main(String[] args) 
{
Article a = new Article((short)66000,"Pen",(float)23.45);
System.out.println(a.getNumeroArticle());
}
 
private short numeroArticle;
private String descriptionArticle;
private float prixArticle;
 
public Article(short pNumeroArticle, String pDescriptionArticle, float pPrixArticle)
{
setNumeroArticle(pNumeroArticle);
setDescriptionArticle(pDescriptionArticle);
setPrixArticle(pPrixArticle);
}
 
public short getNumeroArticle()
{
return numeroArticle;
}
 
public String getDescriptionArticle()
{
return descriptionArticle;
}
 
public float getPrixArticle()
{
return prixArticle;
}
 
public void setNumeroArticle(short pNumeroArticle)
{
if(pNumeroArticle > 1000 || pNumeroArticle <= 0)
throw new IllegalArgumentException("Le numéro de l'article doit être compris entre 1 et 1000");
else
numeroArticle = pNumeroArticle;
}
 
public void setDescriptionArticle(String pDescriptionArticle)
{
descriptionArticle = pDescriptionArticle;
}
 
public void setPrixArticle(float pPrixArticle)
{
prixArticle = pPrixArticle;
}
}

Hi,
Use code tags while posting code.

[r035198x]

Do not cast to short here

         Article a = new Article((short)66000,"Pen",(float)23.45);

Your setMethod that you are calling from the constructor is already doing the check so there is no need to check there as well.

[Nepomuk]

(Is there an error in the QUOTE-Tag?)
Quote from kinghippo423:

package TP1;
 
public class Article 
{
    public static void main(String[] args) 
    {
        Article a = new Article((short)66000,"Pen",(float)23.45);
        System.out.println(a.getNumeroArticle());
    }
 
    private short numeroArticle;
    private String descriptionArticle;
    private float prixArticle;
 
    public Article(short pNumeroArticle, String pDescriptionArticle, float pPrixArticle)
    {
        setNumeroArticle(pNumeroArticle);
        setDescriptionArticle(pDescriptionArticle);
        setPrixArticle(pPrixArticle);
    }
 
    public short getNumeroArticle()
    {
        return numeroArticle;
    }
 
    public String getDescriptionArticle()
    {
        return descriptionArticle;
    }
 
    public float getPrixArticle()
    {
        return prixArticle;
    }
 
    public void setNumeroArticle(short pNumeroArticle)
    {
        if(pNumeroArticle > 1000 || pNumeroArticle <= 0)
            throw new IllegalArgumentException("Le numéro de l'article doit être compris entre 1 et 1000");
        else
            numeroArticle = pNumeroArticle;
    }
 
    public void setDescriptionArticle(String pDescriptionArticle)
    {
        descriptionArticle = pDescriptionArticle;
    }
 
    public void setPrixArticle(float pPrixArticle)
    {
        prixArticle = pPrixArticle;
    }
}

(End of Quote)

As I'm sure you've guessed, it's a problem with the type short. A simple

System.out.println("Max: " + Short.MAX_VALUE);
System.out.println("Min: " + Short.MIN_VALUE);
 

will tell you, that the maximum value for short numbers is 32767 and the minimum is -32768. So the short number 32768 equals the short number -32768, as the line

System.out.println((short)32768 == (short) -32768);
 

will prove.

To solve this problem, I'd change the class, so that it takes integers and then checks, if they are larger than Short.MAX_VALUE. If so, they should be set to a short number, which is too big but in range.

Greetings,
Nepomuk

[kinghippo423]

I tried what you siad but it doesn't work. It is possible to give a working little example of using short arguments and controlled its value to be only between 1 and 1000 no matter what is the value of the arguments?

I'm so lost right now. BTW, if I transform my short into int, I get the same problem because if i go over limit i will have the same problem. I will give a int over 1000 but still be between 1 and 1000 for Java.

[Nepomuk]

I tried what you siad but it doesn't work. It is possible to give a working little example of using short arguments and controlled its value to be only between 1 and 1000 no matter what is the value of the arguments?

I'm so lost right now. BTW, if I transform my short into int, I get the same problem because if i go over limit i will have the same problem. I will give a int over 1000 but still be between 1 and 1000 for Java.

Here's an example:

public void setNumeroArticle(int value) throws IllegalArgumentException
{
    if(value >= 1 && value <= 1000)
    {
        // set the value, which is converted to short
    }
    else // throw an exception
}
 

It's a very simple test, but it does the job.

The trick is, to cast it to short after checking the size.

Greetings,
Nepomuk