org.wicketstuff.datatable_autocomplete.tst.TernarySearchTrie Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of wicketstuff-datatable-autocomplete-common Show documentation

This module provides the Patricia Trie implementation. It is seperated from the main datatable-autocomplete module to allow reuse in non wicket environments.

There is a newer version: 1.5.13

Show newest version

/*
 * 
 * ==============================================================================
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package org.wicketstuff.datatable_autocomplete.tst;

import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;

import org.wicketstuff.datatable_autocomplete.trie.ITrieConfiguration;
import org.wicketstuff.datatable_autocomplete.trie.ITrieFilter;
import org.wicketstuff.datatable_autocomplete.trie.Trie;

/**
 * @author mocleiri
 * 
 *         A ternary search trie is designed to save space by having less nodes.
 * 
 *         It works like a standard trie but instead of having sizeof(alphabet)
 * 
 * 
 */
public class TernarySearchTrie implements Trie
{

	private static final long serialVersionUID = 472990287147515130L;
	private TernaryNode root = null;
	private final ITrieConfiguration configuration;

	/**
	 * 
	 */
	public TernarySearchTrie(ITrieConfiguration configuration)
	{

		this.configuration = configuration;

	}

	public void index(C value)
	{

		String word = this.configuration.getWord(value);

		if (!this.configuration.isIndexCaseSensitive())
			word = word.toLowerCase();

		String firstLetter = word.substring(0, 1);

		if (root == null)
		{

			root = new TernaryNode(null, 0, firstLetter);

		}


		root.index(word, value);


	}

	public List getWordList(String prefix, int limit)
	{

		List wordList = new LinkedList();

		TernaryNode prefixNode = root.matchPrefix(prefix);

		if (prefixNode != null)
			prefixNode.collect(wordList);

		return wordList;
	}

	public List getWordList(String prefix)
	{

		return this.getWordList(prefix, -1);

	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.wicketstuff.datatable_autocomplete.trie.Trie#getWordList(java.lang .String,
	 * org.wicketstuff.datatable_autocomplete.trie.ITrieFilter, int)
	 */
	public List getWordList(String prefix, ITrieFilter filter, int limit)
	{
		/*
		 * TODO: add support for TrieFiltering
		 */
		return getWordList(prefix, limit);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.wicketstuff.datatable_autocomplete.trie.Trie#getWordList(java.lang .String,
	 * org.wicketstuff.datatable_autocomplete.trie.ITrieFilter)
	 */
	public List getWordList(String prefix, ITrieFilter filter)
	{
		/*
		 * TODO: add support for TrieFiltering
		 */
		return getWordList(prefix);
	}

	public void visit(TernaryNodeVisitor visitor)
	{

		visitor.preVisit();

		root.visit(visitor);

		visitor.postVisit();
	}

	/**
	 * 
	 * @return the Set for the starting (level 0) characters in the index.
	 * 
	 */
	public Set getNextNodeCharacterSet()
	{

		Set levelZeroSet = new LinkedHashSet();

		root.getStartingCharacterSet(levelZeroSet);

		return levelZeroSet;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.wicketstuff.datatable_autocomplete.trie.Trie#postIndexing()
	 */
	public void postIndexing()
	{
		// TODO Auto-generated method stub

	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.wicketstuff.datatable_autocomplete.trie.Trie#preIndexing()
	 */
	public void preIndexing()
	{
		// TODO Auto-generated method stub

	}


	/**
	 * @return the root
	 */
	public TernaryNode getRoot()
	{
		return root;
	}

	public void printTree()
	{

		/*
		 * _N_ | \
		 * 
		 * build all down less than then level ordered from there. back up until an unrendered left
		 * is encountered.
		 */


	}

}