Thread: Java ... I Need Your Help so I Can Help My Son

TS, if you want me to I can post it or if you prefer the community to answer direct questions let me know. I understand Norm thinking, and I don't want to rob you of an education. There's a personal satisfaction of working through the problem.

I followed the coding convention, variables and method start with a lower case and every first word a Upper Case.

The guess() method should return a value to the user but at this point I just want to see "Enter your guess: " on the terminal screen. Perhaps I am not following what you are trying to teach me.

import java.util.*;
 
public final class NumberTwoXe{    
    public static void main(String[] args){   
        Random Rand = new Random();
            for(int x = 0; x < 100; x++);//Makes a random number less than 100{    
            int number;
            number = (int)(Math.random() * 100);//Chooses the amount of numbers that can be randomly generated
            System.out.println(number + " = Random Number");//Prints the number that is made. Block this line using comment statement when done coding            
    }
 
 
    public static void guess(){
        Scanner input = new Scanner (System.in);
        System.out.println("Enter your guess:  ");
        int guess;
        guess = input.nextInt();
    }
 
 
}

Can you explain this part of the code:

for(int x = 0; x < 100; x++)

Norm,

I appreciate you guiding me in the right direction. I spent hours trying to figure this out all morning. I know you gave me some hints but I am not getting it. Again, my approach is one bit of code for every action or in this java case method().

I changed the coding up to meet proper java convection, but still can't make these two methods function together. As individual method(), they work. The program should respond like:

18 = Random Number
Enter your answer:

 
import java.util.Random;
import java.util.Scanner;
 
public class NumberTwoX{    
    public static void main(String[] args){   
        Random Rand = new Random();
        int number;
        number = (int)(Math.random() * 99 + 1);//Chooses the amount of numbers that can be randomly generated
        System.out.println(number + " = Random Number");//Prints the number that is made. Block this line using comment statement when done coding            
    }
 
 
    public static void guess(){
        Scanner input = new Scanner (System.in);
        System.out.print("Enter your answer:  ");
        int answer;
        answer = input.nextInt();
 
    }
 
 
}

I give up ... hours spent and can't make it work per method. Works if I just remove this string of code:

 
        }
 
    public static void guess(){

Ok ... more reading and still can't figure out how to make both of these two method() work together. Anymore reading and I am positive that it can't be done without removing one line of code.


Thanks for you

Post the code you have so far and a question about it. I have a hard time knowing what your question is at this point.

 Have you tried Google about: how to call a method

I tried everything you suggested and Google. At my current level of "Self Tutoring", Java or any other programing is just not for me. Been there back in 1977, taking a class in Fortran, didn't do good at all. Tried to self teach myself Basic to program a PIC chip as I am all into electronics. Only thing I got out of the Basic Self Tutoring Guide is the hardware, books, and dust.

And today, inspired to learn Java since I now have a teenager taking a class. Programing is just not for me! Only so much I can read and research and every book and tutoring starts out with "Hello World". Nothing mention about the Java API Library, or the break down of method statement like "static", "main". As they say, it will all be discuss later on in the chapter so for now just take it as it is.

I was fortunate to find a "Cheat Sheet" on Java. I'll give this a day or two and then I'll close this Topic....I guess you can say I am exhausted reading, reading, guessing and not getting an understanding.

Originally Posted by GIban

...I have two method(), the first method() generates a random number, the second method() asks for a user input. The first method() outputs a number but the second method does not. If I remove this part of the code

}
public static void guess(){

Have you given any thought as to WHY removing those two lines has the effect that it does?

Originally Posted by GIban

I get the result I want. I am trying separate the code in blocks so that each block of code can be used later in other programs.

That is one of the basic ideas involved with object oriented programming. Good thinking.

Originally Posted by GIban

... how to interface each block.

That is the problem you are fixing by removing the two lines of code.

In your code the way it is, (with the code NOT removed), the JVM 'calls' your main method. That is how it all starts, (as far as your code and this discussion goes). Execution starts at public static void main(String[] args) {
That open curly brace on that line is the marker that says beginning. When the JVM called your method, it called for a complete block of code to be executed. We just discussed the start marker. The end marker is the marker on the first of the two lines you remove to get it to do what you want. So when your main method is called those defining markers say execute all code between { and the corresponding }. In this case 4 lines of code.

In your code with the two lines removed, you are extending the scope of your main method to include 4 more lines of code. Now when main is called, 8 lines of code are executed instead of 4. Do you see how this changes what you have told the computer to do?

Now look at what happens without removing the lines of code. You said run 4 lines of code when main is called. main is called by the JVM and is considered the starting point for your program. This is why the 4 lines in the body of main are executed. Somewhere behind the scenes, hidden away from you, is a line of code that basically says: main(args); that causes your code to execute. What Norm has been trying to tell you, you have not said for your other lines of code to ever be executed. So they don't ever execute. If you want a method to run, you have to call the method. When you want the method to run, is where you call it. You have to call your guess method to be executed from code that is being executed somewhere. (In this program there is a short list of options). If this seems confusing try searching "calling a method" and "using method return" and feel free to ask more questions.

But don't get discouraged. It is really hard to see the bigger picture when you are being force-fed random pixels from the pattern. Being a survivor from your rowboat myself, proudly wearing the scars of war, how ever you like to see it, it just takes practice.

Sounds like it's time to get the teenager more involved.

Yes, I am hoping he enjoys programing and will stay with it as I got some PIC circuits that I would like for him to program. Or, even better, teach is Ol man how to. An old project hidden in the closet.

You have identified the problem and a solution:
You were not calling your method, and now you are, but not doing so correctly. You are calling in a good place. So most of your problem is fixed.
What you have in your code for calling the method looks more like creating an object than calling a method. Check out some of the links Norm posted about calling methods, and consider the examples he quoted from your code showing method calls you are already making.