private void ensureBufferAvailable(TableBlock block) throws IOException {
        if (!block.hasBuffer()) {
            synchronized (this) {
                if (!block.hasBuffer()) {
                    ByteBuffer buffer = getBuffer();
                    block.setBuffer(buffer);
                }
            }
        }
    }
private void ensureBufferAvailable ( TableBlock block ) throws IOException { if ( ! block . hasBuffer ( ) ) { synchronized ( this ) { if ( ! block . hasBuffer ( ) ) { ByteBuffer buffer = getBuffer ( ) ; block . setBuffer ( buffer ) ; } } } }
Checks whether the given block has a buffer assigned to it.  If not, it synchronously gets an available buffer
and assigns it to the block.