error: non-static method PostFixConverter(String) cannot be referenced from a static context

Question

I'm doing some hw and am currently stumped. It gives an interface and a class for ArrayStack and asks to write a code that converts infix to postfix. In my main method is this line

PostFixConverter(infixExpression);

which calls to a method that calculates the postfix expression. My problem is that the class ArrayStack is not static but my main method is, so how can I resolve this?

Also,

Am I converting infix to postfix wrong by not making a new class that calculates postfix because all other code I've seen that does this has a separate class for it? Is there an advantage to doing it that way?

Thank You!

either make the method static or create instance of class and then call the method. — Prasad Kharkar, Mar 03 '16 at 05:30

score 0 · Answer 1 · answered Mar 03 '16 at 05:32

0

Create Object of your class in main method like following and call non static(instance method)

ArrayStack arrayStack = new ArrayStack();                                        
arrayStack.postFixConverter(infixExpression);

answered Mar 03 '16 at 05:32

AGdev

616
8
12

score 0 · Accepted Answer · answered Mar 03 '16 at 05:32

0

For first query refer below:

public static void main (String[] args)
{
    String infixExpression = "Your infix string";
    PostFixConverter(infixExpression);  
}

private static void PostFixConverter(String infixExpression) 
{
    //your code goes here
}

For second query, it's your choice to do it that way.

answered Mar 03 '16 at 05:32

sAm

319
2
20

changed method to private static void PostFixConverter(String infixExpression){ and it now compiles!Thank You! However new problems have arisen. – EmsandEms Mar 03 '16 at 05:55
please share the issue. – sAm Mar 03 '16 at 05:59
My program is suppose to read from a file that has infix expressions, print them out, convert to postfix and print that out. Output Example: Infix expression = ((9/3)-2) Postfix expression = 93/2- The file reading is good. However when I run my program it prints out the infix expression and just keeps running. Nothing else happens. Would it help is I made question about it? – EmsandEms Mar 03 '16 at 06:04
you can add new question with code snippet. – sAm Mar 03 '16 at 06:06
Fixed the running thing by adding else's to some if's. If I am stuck again I shall ask. Thanks! – EmsandEms Mar 03 '16 at 06:18

error: non-static method PostFixConverter(String) cannot be referenced from a static context

2 Answers2