CODEWITHSUNDEEP
javaclass
FriedOrangeSlice
FriedOrangeSlice

Reputation: 1

How to combine two classes in java

Right now I have both of these in separate java files, but I can't seem to figure out how to combine them both together. When I combine them and run it usually only one class will actually work and the other doesn't do anything. I've tried getting rid of one class and combining them into one large class but then I get the error error: method main(String[]) is already defined in class lapTimes public static void main (String[] args)

class GFG
{

    static void ConvertSectoDay(int n)
    {

        n %= 3600;
        int minutes = n / 60 ;

        n %= 60;
        int seconds = n;

        System.out.println( minutes + " "
                           + "minutes " + seconds + " "
                           + "seconds ");
    }

    public static void main (String[] args)
    {
        
        int n = 200;
        ConvertSectoDay(n);

    }
}

public class lapTimes {
    
  public void lap1(int lap) {
    System.out.println("How many seconds for lap one: " + lap);
  }
  public void lap2(int lap) {
    System.out.println("How many seconds for lap two: " + lap);
  }
  public void lap3(int lap) {
    System.out.println("How many seconds for lap three: " + lap);
  }
  public void lap4(int lap) {
    System.out.println("How many seconds for lap four: " + lap);
  }
   
  public static void main(String[] args) {
    lapTimes run = new lapTimes();   
    run.lap1(34);
    run.lap2(54);
    run.lap3(43);
    run.lap4(61);              
  }
}

Upvotes: 0

Views: 1002

Answers (1)

Stephen C
Stephen C

Reputation: 719006

If you put all of the methods in your GFG and lapTimes classes into a single class, you obviously have two methods called main with arguments String[] args. That is not valid Java.

You cannot have two static methods (or two instance methods) with the same and the same argument types ... in the same class.

Why? Because if you did, then Java would not know which method to use when something calls main ...

So, if you want your combined class to do the stuff done by both existing main methods, then the obvious solution is to combine the main methods into one; e.g.

public static void main(String[] args) {
    int n = 200;
    ConvertSectoDay(n);

    NewClass run = new NewClass();   
    run.lap1(34);
    run.lap2(54);
    run.lap3(43);
    run.lap4(61);              
}

But this looks conceptually wrong. You now have a class that represents both a 4 lap race ... and ... whatever a GFG is supposed to represent.

  1. You should use class names that indicate the purpose of the class. (I have know idea what GFG means!)

    It only takes a few seconds to type a descriptive name. Choosing an appropriate name may take a bit longer ... but it will take far more time for someone else to understand your code if you use opaque names. You should be writing your code for other people to read. (The other people includes yourself, in 5 years time, when you have totally forgotten what the GFG class is supposed to do.)

  2. You should not combine unrelated abstractions and functions into a single class. It makes your code confusing.

  3. You should follow Java style rules for identifiers:

    • A class name should not start with a lowercase letter.
    • A method name should not start with a uppercase letter.

Upvotes: 1

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