Question

I tried

cache = new Vector<CacheBlock>(1024);
...
cache.add(10, blk); // gives index out of bounds

So is it impossible to insert (into specified index) into an empty list? Or how might I fill up all elements if the Vector, with null or otherwise, so I can accomplish this?

Answer 1

You could use setSize() to make sure your cache is big enough before you insert elements:

setSize

public void setSize(int newSize)

Sets the size of this vector. If the new size is greater than the current size,
new null items are added to the end of the vector. If
the new size is less than the current size, all components at index
newSize and greater are discarded.

cache = new Vector<CacheBlock>(1024);
cache.setSize(11);
cache.add(10, blk);