No main methods found

Question

package CS1301;

public class Homework4 {

    public static void Questions(int value) {
        if (value > 0) {
            int count = 1;

            while (count <= value) {
                if (value % count == 0) {
                    System.out.println(count);
                }  

                count = count ++;
            }
        }
    }
}

So I have been trying to get this to work for a bit now and I cant seem to find what is I'm doing wrong. When I try to run it it says "no main methods found, but I though the method defined by public static void. Also the purpose of this was to find the factors of the value. This is my first program so any pointers on better formatting would also be appreciated.

I don't see a `main` method in there. – Joe C Sep 23 '17 at 20:31 — Joe C, Sep 23 '17 at 20:31

score 4 · Accepted Answer · edited Sep 23 '17 at 20:37

4

You must have a public static void method called main, which accepts an array of arguments;

package CS1301;

public class Homework4 {

    public static void Questions(int value) {
        if (value > 0) {
            int count = 1;

            while (count <= value) {
                if (value % count == 0) {
                    System.out.println(count);
                }  

                count = count ++;
            }
        }
    }

    public static void main(String[] args) {
        Questions(5);
    }
}

edited Sep 23 '17 at 20:37

Jack Wilsdon

6,706
11
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answered Sep 23 '17 at 20:34

Coder

1,175
1
12
32

You're using the incorrect parameter for the `main` method. – Jacob G. Sep 23 '17 at 20:35
Alright I got it to work, but I wanted to ask what exactly 'public static void' meant in the context I used it in originally. Do I actually need it? Also, how do I use the ++ operator correctly? – user8662311 Sep 23 '17 at 21:23
1

The duplicate question explain what each of those words meant. The ++ operator is a separate question (which has probably already been answered about 25 times on this site). – Joe C Sep 23 '17 at 21:30
1

@user8662311 Check out [public static void main meaning](https://stackoverflow.com/questions/29276917/what-does-public-static-void-main-args-mean?noredirect=1&lq=1) and [++ meaning](https://stackoverflow.com/questions/2371118/how-do-the-post-increment-i-and-pre-increment-i-operators-work-in-java) – Coder Sep 23 '17 at 21:31

azro · Answer 2 · 2017-09-23T20:56:38.380

In java, to be able to launch something, you need a particular type of function, which can be recognize at the start point of the code

it have to be a void method
its name is main
its parameter have to be an array of String (used in command-line)

Like this :

public static void main(String[] args){
    // some code like computation
    // or function calls 
}

Further details at Oracle Doc

So you have two option, put your code inside this method, or inside an another one :

public static void questions(int value){
    // ... your code
}

public static void main(String[] args){
    questions(2);
    questions(19);
}

OR

public static void main(String[] args){
    int value = 5;                     // <-- and put you value here
    if (value > 0) {
        int count = 1;
        while (count <= value) {
           //...
        }
    }
}

first way is preferable your clarity
better respect conventions and start naming variables and methods name with lover case Questions -> questions

I didn't downvote you, but you should follow conventions yourself ;) — Jacob G., Sep 23 '17 at 20:49
Sometimes you have spaces between the ends of your methods, and sometimes you don't. Your main method also doesn't compile, as `question` is not a method. — Jacob G., Sep 23 '17 at 20:55

No main methods found

2 Answers2