Non-Static Call - IntelliJ Thinks It's Being Accessed From Static Method

Question

I have read this question, but my issue is different because mine isn't about this error message specifically; I was just using it to realize I had made a different kind of mistake. Please read my answer to my question - if you still feel like this is a duplicate, feel free to mark it as such.

I have an object, GeoLocation, and I'm trying to use a non-static method (distanceFrom()) from that object in my code. Understandably, I got a Non-static variable cannot be referenced from a static context when trying to call it from a psvm. So, using advice from this page, I tried moving the call to various other parts of my code. However, I keep getting the same message, even if I'm not making the call from a static context. Here's my code:

public class GeoLocationClient {

    /*1 stashStudio = GeoLocation.distanceFrom();*/

    public static void main(String[] args) {
        GeoLocation theStash = new GeoLocation(34.988889, -106.614444);
        System.out.println("the stash is at " + theStash.toString());

        GeoLocation ABQStudio = new GeoLocation(0.0, 0.0);
        System.out.println("ABQ studio is at " + ABQStudio.toString());

        GeoLocation FBIBuilding = new GeoLocation(0.0, 0.0);
        System.out.println("FBI building is at " + FBIBuilding.toString());


        System.out.println("distance in miles between:");
    }

    public void distances(GeoLocation place) {
    /*2    double stashStudio = GeoLocation.distanceFrom();*/
    }
}

At point 1 I'm calling distanceFrom() inside the non-static class, but outside of psvm. At point 2, I'm calling it in a non-static method. But in both cases, I still got the error message. Why is intelliJ seemingly thinking that my whole java file is static?

Here's the object class:

// This class stores information about a location on Earth.  Locations are
// specified using latitude and longitude.  The class includes a method for
// computing the distance between two locations.

public class GeoLocation {
    public static final double RADIUS = 3963.1676;  // Earth radius in miles

    private double latitude;
    private double longitude;

    // constructs a geo location object with given latitude and longitude
    public GeoLocation(double theLatitude, double theLongitude) {
        latitude = theLatitude;
        longitude = theLongitude;
    }

    // returns the latitude of this geo location
    public double getLatitude() {
        return latitude;
    }

    // returns the longitude of this geo location
    public double getLongitude() {
        return longitude;
    }

    // returns a string representation of this geo location
    public String toString() {
        return "latitude: " + latitude + ", longitude: " + longitude;
    }

    // returns the distance in miles between this geo location and the given
    // other geo location
    public double distanceFrom(GeoLocation other) {
        double lat1 = Math.toRadians(latitude);
        double long1 = Math.toRadians(longitude);
        double lat2 = Math.toRadians(other.latitude);
        double long2 = Math.toRadians(other.longitude);
        // apply the spherical law of cosines with a triangle composed of the
        // two locations and the north pole
        double theCos = Math.sin(lat1) * Math.sin(lat2) +
            Math.cos(lat1) * Math.cos(lat2) * Math.cos(long1 - long2);
        double arcLength = Math.acos(theCos);
        return arcLength * RADIUS;
    }
}

Answer 1

You are calling the method as a class method, when instead you should be calling it on an instance of the class. Instead of GeoLocation.distanceFrom() you need to be calling (say at point 2) place.distanceFrom()