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I'm trying to call my createFile method from the OpenFile class in my main method, but I keep getting the error saying that I cannot call a non-static variable from a static context.

I did try calling OpenFile of = new OpenFile(); inside my main method, but that didn't work so I'm currently declaring OpenFile above my main method which works fine, however every time I try to use one of OpenFiles methods I get the same error.

I've tried prefacing a few things with static but that just causes my IDE to show an Erroneous sym type error, which I think is caused by whatever is causing the other error.

Here is createFile from OpenFile:

public class OpenFile { private Formatter file; public void createFile() throws FileNotFoundException{ try{ file = new Formatter("test.txt"); } catch(Exception e) { System.out.println("Error creating file."); } }

and here is my main method:

OpenFile of = new OpenFile(); public static void main(String[] args) { // TODO code application logic here of.createFile(); intro(); createAndShowRibbon(); createAndShowNormalUI(); }

Is it something to do with Formatter? I've never used it before.

Thanks.

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OpenFile of = new OpenFile();

should be 

static OpenFile of = new OpenFile();

You're accessing it from your static void main method. If this variable is not declared static, it will not be available to the method when it is statically executed.

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3 Comments

Seems to run! Although it runs when I add static to OpenFile but only when I also add throws FileNotFoundException to the main method, what's up with that?
@JoshJahans: you are calling of.createFile(); which throws that very same exception. Since it's being thrown there instead of caught (using try { } catch { }), it has to be either thrown or caught in the next method, main in this example.
You can't call something that doesn't exist. Since you haven't created an object, the non-static method doesn't exist yet. A static method (by definition) always exists.
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Since main method in java is most popular method among all beginners and they try to put program code there they face "non-static variable cannot be referenced from a static context" compiler error when they try to access a non static member variable inside main in Java which is static.

Please take a look at this article
Why non-static variable cannot be referenced from a static context?

In your case you have to make the OpenFile of = new OpenFile(); instantiation to be static like as shown below in order to access that in main method which is a static method.

static OpenFile of = new OpenFile(); // should be static for accessing within main method public static void main(String[] args) { of.createFile(); intro(); createAndShowRibbon(); createAndShowNormalUI(); }
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The following is non-static.

OpenFile of = new OpenFile();

But you're calling it from a main method, which is static.

Try changing to:

static OpenFile of = new OpenFile();
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in the static method u can call Class methods or variables which is static but u can't call instance variables or method in

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