i need massive help

[jay bob]

1)generateArray populate array with 35 random numbers from 1-100

2)getElement: returns the value of the element of the array specified by a parameter passed to a method. this will be called with a statement suck as number= getElement(25);

3)printArray from 0-34

4)main method call generate Array, printArray, then repeatedly asks the user which element they like to see, and display that element using getElement, until the user enter -1

i managed to get number 3) down and 1)..sort of but i have no idea how to do the getelement method and the main method, btw i'm doing this on the program known as bluej and i need a lot of help please

[fred rosenberger]

we don't hand out answers to homework here, but folks will bend over backwards to help you. Show us what you've done and tell us what works (and what doesn't), and you'll get tons of responses.

[Wouter Oet]

Couple of hints:

You can get element x by calling: number = array[x];
Main method looks lite this: public static void main(String[] args) or public static void main(String... args)
One way of getting input is the Console class

Advice:
Read some java tutorials.

[jay bob]

fred rosenberger wrote:we don't hand out answers to homework here, but folks will bend over backwards to help you. Show us what you've done and tell us what works (and what doesn't), and you'll get tons of responses.

um well, i failed this part of my homework and i honestly have no clue what to do well sorta but i don't got the right idea.

[jay bob]

jay bob wrote:

fred rosenberger wrote:we don't hand out answers to homework here, but folks will bend over backwards to help you. Show us what you've done and tell us what works (and what doesn't), and you'll get tons of responses.

um well, i failed this part of my homework and i honestly have no clue what to do well sorta but i don't got the right idea.

edit: ok heres what i got so far could someone please PLEASE correct this for me

/**
 * Write a description of class fianlSummative here.
 * 
 * @author (jay) 
 * @version (bluej)
 */

    import java.lang.Math;
    import java.util.Scanner;

public class finalSummative
{
    int[]array;
    int randomNumber;

   
    /**
     * Constructor for objects of class finalSummative
     */
    public finalSummative()
    {
        array = new int[35] ;
    }
    
    


    // instance variables - replace the example below with your own
    public void generateArray()
    {
        randomNumber = (int)(100*Math.random()+1);
       
        
    }
    
    /**
     * Constructor for objects of class fianlSummative
     */
    public void printArray()
    {
        for (int i=0; i <= 34; i++)
  System.out.println("Element:" + getElement( i ));
        }
        
    }

    /**
     * An example of a method - replace this comment with your own
     * 
     * @param  y   a sample parameter for a method
     * @return     the sum of x and y 
     */
    public int getElement(int randomNumber)
    {
        return array[randomNumber];
      
    }
    
    private void mainMethod()
    {
        Scanner input = new Scanner(System.in);
        
        generateArray();
        
        printArray();
            
        if(randomNumber>0){
            System.out.println("please enter in an element you want to see: ");
            
        }else if(randomNumber<0){
            System.out.println("please enter an element that is higher than -1");
    }
}
}

[Henry Wong]

Take a look at the java.util.Random class.

Henry

[Campbell Ritchie]

Since you are new (welcome to the Ranch ) and haven't used the Code button before, I have edited your post and you can see how much better it looks. There appear to be some spelling errors, and spacing/indentation irregularities; whenever you post code be sure to use copy and paste so we see the actual code. People will be better able to help if your thread title tells them what the problem is.

What is your mainMethod for? It is private and you don't appear to call it anywhere, so it will never do anything. You are reminded the format of a main method would be something like this

public class ArrayDemo
{
   public static void main(String[] args)
   {
       new SomeClassOrOther.doSomething();
   }
}

This depends on there being a class called SomeClassOrOther which has a doSomething() method.

I would also remind you of the conventional way to write a for loop to iterate an array

for (int i = 0; i < myArray.length; i++)
{
   . . .
}//end for

The "end" comment is not essential; I like it, some other people don't.

The reason that convention has grown up is that you can apply arrays of any size to that for loop secure in the knowledge you will never go beyond the confines of the array. Writing <= 34 is error-prone; the tiniest mistake can cause nasty errors.
There is another version of that for loop, and I'll leave you to work out how it works.

for (int i = myArray.length - 1; i >= 0; i--) . . .

The enhanced for loop is good when you want the array elements to be iterated in "read-only" mode. It is described in the Java™ Tutorials; for (int i : numbers) . . . is pronounced "for each int i in numbers . . . " but you mustn't try writing
i = anything;

[fred rosenberger]

Every single time I start a new program, I write the following:

public class myClass
{
  public static void main(String [] args)
  {
    System.out.println("In main");
  }
}

I compile that, run it, make sure it works (it usually does), and then i go back and start adding more code. I try to ONLY ad 1-2 lines before i again re-compile, debug, test, fix, etc. it's only after I'm sure each line is right do I start adding more.

what you seem to have done is written 74 lines of code without testing. This is a recipe for disaster. If there is a problem, how do you know where to start looking?

I honestly thing the best advice would be to throw all this away, and start over. Focus on Item 1 and make sure you have it working 100% before you even attempt anything else. Note that sometimes you have to write 'throw away' code to test this stuff. For example, I might write a method that prints out all the elements in an array. Even though you'll never use it in your final program (i.e. it doesn't do anything required by your specs), you need it to verify that some other parts of your code work.

[Greg Charles]

Beginning programming is the hardest. Everything is new and mysterious, and so beginners just try to keep tweaking things and hope everything falls in place. Incidentally, that's how I started trying to solve a Rubik's Cube. I figured if I kept turning it long enough, I would eventually solve it. Unfortunately, that theory was only good if "eventually" meant several thousand lifetimes, which was more time than I was willing to dedicate to the project.

You've got some good advice already. Break the problem into small tasks and solve them one at a time. Also, try not to get frustrated. Everyone has to go through this stage. From what I see, you've done a lot of things right already. For example, you've done the random number exactly right as far as I can tell, and that's easy to get wrong. Something you may want to look at though: printArray() has a loop; shouldn't generateArray() have one too?