My program tells me that my method is undefined for my type what does that mean?-Collection of common programming errors

I wrote a code that is supposed to take an array and sort it from smallest value to largest, but I get an error. this is the code

public class minHeapify{
    public static void exchange(int a[],int i,int j) {
        int temp = a[i];
        a[i] = a[j];
        a[j] = temp;
    }
    public static int parent(int i) {
        return (int) Math.floor((i - 1)/2);
    }
    public static int left(int i) {
        return 2*i + 1;
    }
    public static int right(int i) {
        return 2*(i+1);
    }
    public minHeapify(int a[], int start,int end) {
        int l = left(start); int r = right(start);
        int smallest;
        if(l >= end){
            smallest = (a[l] < a[start])? l: start;
        }
        if(r >= end){
            smallest = (a[r] < a[smallest])? r: smallest;
        }
        if(smallest != start) {
            exchange(a,start,smallest);
            minHeapify(a,smallest,end);
        }
    }
} 

the error that I get is ” The method minHeapify(int[], int, int) is undefined for the type minHeapify” and im not sure what that means.

1. The problem is that the method has the same name as the class and has no return type. Therefore, from the compiler’s point of view, it’s a constructor rather than an ordinary method. And a constructor can’t call itself in the manner your method is trying to.

   Rename the method and add a return type. If the method needs to be automatically invoked upon construction, simply call it from the constructor.

2. Java thinks that public minHeapify(int a[], int start,int end) is a constructor, not a normal method. You can fix it by respecting the convention that class names are uppercase: public class MinHeapify.

Originally posted 2013-11-27 12:02:07.