public Block cloneAsHeader() {
        Block block = new Block(version, prevBlockHash, getMerkleRoot(), time, difficultyTarget, nonce, null);
        block.hash = getHash();
        return block;
    }
@Test
    public void testHeaderParse() {
        Block header = block700000.cloneAsHeader();
        Block reparsed = TESTNET.getDefaultSerializer().makeBlock(ByteBuffer.wrap(header.serialize()));
        assertEquals(reparsed, header);
    }