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General Discussion

Posted by Adam Smallman
Adam Smallman
4,182 Points

Simple Java error with float

Hi guys, I am doing some simple Java programming.

I am having an issue with the float while using

System.out.println

I am using the Terminal to run my Java programmes.

So here is the code 

class simplejava
{
    float d = 8.8f;
    float b = 1.98f;
    float p = 63.23f;

    public static void main (String [] args) 
    {
        System.out.println( d + b + p );   
    }

}

I am getting errors on all three of the floats

Here is the float errors that the Terminal gives out.

simplejava.java:9: non-static variable d cannot be referenced from a static context System.out.println( d + b + p );
^ simplejava.java:9: non-static variable b cannot be referenced from a static context System.out.println( d + b + p );
^ simplejava.java:9: non-static variable p cannot be referenced from a static context System.out.println( d + b + p );
^ 3 errors

Thank you for any help with this guys!

Also, sorry if this post is not in the write place. I though putting this in the Android post would not really be the right place!

1 Answer

Ben Rubin
Ben Rubin
Courses Plus Student 14,658 Points

Your main function is static and your variables are not static. You can't access a non-static member variable from a static method. You can fix that error by making all of your member variables static.

For this little example, it's fine to fix the problem by making all of the member variables static However, in a real program, you probably wouldn't want to do that. It's best to put all of the actual program logic inside other classes that don't use static members and static methods very often. For example, you could do it like this to avoid using static members:

public class MyClass
{
   float d = 8.8f;
   float b = 1.98f;
   float p = 63.23f;

   public void printMembers()
   {
       System.out.println( d + b + p );   
   }
}

class simplejava
{
    public static void main (String [] args) 
    {
        MyClass myClass = new MyClass();
        myClass.printMembers(); 
    }
}
Adam Smallman
Adam Smallman
4,182 Points

Thanks Ben!