// sig = "228"
	@Override
	public Set<String> signatureToWords(String signiture)
	{
		Set<String> matching = new HashSet<String>();

		if (i == signiture.length())
		{
			if (i==0)
			{
				throw new IllegalArgumentException("Word must not be null");
			}
			else
			{
				for (int j=0; j<currentTree.getValue().size(); j++)
				{
					matching.add(currentTree.getValue().get(j));
				}
				System.out.println("matching words added.");
				System.out.println("matching"+ matching);
			}
			System.out.println("matching set size: " + matching.size());
			return matching;
		}
		else
		{
			if (i < signiture.length())
			{
				if (signiture.charAt(i) == '2')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT2();
					}
					else
					{
						currentTree = currentTree.getT2();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '3')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT3();
					}
					else
					{
						currentTree = currentTree.getT3();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '4')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT4();
					}
					else
					{
						currentTree = currentTree.getT4();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '5')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT5();
					}
					else
					{
						currentTree = currentTree.getT5();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '6')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT6();
					}
					else
					{
						currentTree = currentTree.getT6();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '7')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT7();
					}
					else
					{
						currentTree = currentTree.getT7();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '8')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT8();
					}
					else
					{
						currentTree = currentTree.getT8();
					}
					i+=1;
					signatureToWords(signiture);
				}
				else if (signiture.charAt(i) == '9')
				{
					if (i==0)
					{
						currentTree = dictionaryTree.getT9();
					}
					else
					{
						currentTree = currentTree.getT9();
					}
					i+=1;
					signatureToWords(signiture);
				}
			}
			System.out.println("matching size is now: " + matching.size());
		}
		return matching;
	}