DAWG collapsing

gistfile1.java

	@Test
	public void testDawgDictionaryCollapse() {
		Dictionary dictionary = Dictionary.buildDefaultDictionary();
		Trie trie = new Trie(dictionary);
		Dawg dawg = new Dawg(dictionary);
		assertEquals(395184, trie.countNodes());
		int i=0;
		
		//Despite the merged nodes, a dawg should look structurally the same as a trie.
		TrieIterator t = trie.iterator(), d = dawg.iterator();
		while(t.hasNext() && d.hasNext()) {
			Trie.Node tn = t.next(), dn = d.next();
			for(char letter='A';letter<='Z';letter++)
				assertEquals( tn.getChild(letter)!=null, dn.getChild(letter)!=null );
			i++;
		}
		assertFalse(t.hasNext());
		assertFalse(d.hasNext());
		assertEquals(395184, i);
		assertTrue( trie.countNodes() > dawg.countNodes() );
	}