Heap Sorting

[kesav2005]

I m facing a error in this program...can any body help me in this regard.
im pasting my code below.
Its throwing a error message
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 9

Code:

class Heapsort 
{ 
    public static void main (String args[]) 
    { 
        int array[]={55,40,80,65,71}; 
        int i; int j; int tmp; 
 
        for(i=array.length/2-1; i>=0; i--) 
        { 
            j=2*i+1; 
            while (j<array.length) 
            { 
                if(j+1<array.length) 
                    if (array[j+1]>array[j]) j++; 
 
                if(array[i]>=array[j]) 
                { 
                    tmp=array[i]; 
                    array[i]=array[j]; 
                    array[j]=tmp; 
                } 
                i=j; j=2*i+1; 
            } 
 
            while(array.length>1) 
            { 
                array[i]--; 
                tmp=array[i]; 
                array[i]=array[j]; 
                array[j]=tmp; 
                if(j+1<array.length) 
                    if (array[j+1]>array[j]) j++; 
 
                if(array[i]>=array[j]) 
                { 
                    tmp=array[i]; 
                    array[i]=array[j]; 
                    array[j]=tmp; 
                } 
                i=j; j=2*i+1; 
            } 
 
        }
        System.out.print(" " + array); 
    } 
}

[ShoeNinja]

On the first iteration of the for loop, i=1 and j=3. During the while loop, j is incremented. At the end of the while loop, i=j (which is now 4) and j becomes 2*i+1 (9). In the second while loop, the statement array[i]=array[j] causes the exception because j is 9. I could be wrong though.