source: gs3-extensions/atlas-src/trunk/src/org/greenstone/server/GazetteerTrieSmallNode.java@ 22272

package org.greenstone.server;

import java.io.Serializable;
import java.util.HashMap;

public class GazetteerTrieSmallNode implements Serializable
{
    private static final long serialVersionUID = 8121262849365540679L;
    protected boolean _nameEnd = false;
    // protected GazetteerTrieSmallNode[] _children = new
    // GazetteerTrieSmallNode[26];
    protected HashMap<Character, GazetteerTrieSmallNode> _unicodeCharacters = null;

    /**
     * Basic constructor for a non-unicode trie node
     * 
     * @param nameEnd
     *            defines whether the new node represents the end of a place
     *            name
     */
    protected GazetteerTrieSmallNode(boolean nameEnd)
    {
        _nameEnd = nameEnd;
    }

    /**
     * Add a child to the current node
     * 
     * @param c
     *            is the character used to decide where to add the child node
     * @param nameEnd
     *            is whether or not this character represents the end of a place
     *            name
     * @return true if a child was added and false if one already existed
     */
    protected boolean addChild(char c, boolean nameEnd)
    {
        if (c >= 65 && c <= 90)
        {
            c += 32;
        }
        // If the node does not currently have a unicode character map then make
        // one
        if (_unicodeCharacters == null)
        {
            _unicodeCharacters = new HashMap<Character, GazetteerTrieSmallNode>();
            _unicodeCharacters.put(c, new GazetteerTrieSmallNode(nameEnd));
            return true;
        }

        // Add the unicode character to the map only if it either does not exist
        // already or signifies the end of a place name
        GazetteerTrieSmallNode value;
        if ((value = _unicodeCharacters.get(c)) != null)
        {
            if (value.isNameEnd())
            {
                return false;
            }
            else
            {
                value.setNameEnd(nameEnd);
            }
        }
        else
        {
            _unicodeCharacters.put(c, new GazetteerTrieSmallNode(nameEnd));
        }

        return true;
    }

    /**
     * @return whether or not this node represents the end of a place name
     */
    protected boolean isNameEnd()
    {
        return _nameEnd;
    }

    /**
     * Set whether or not this node represents the end of a place name
     * 
     * @param nameEnd
     *            is the value to set it to
     */
    protected void setNameEnd(boolean nameEnd)
    {
        _nameEnd = nameEnd;
    }

    /**
     * Returns the child at the given index
     * 
     * @param index
     *            is the index of the child to return
     * @return the child at the given index
     */
    protected GazetteerTrieSmallNode getChild(char c)
    {
        if (c >= 65 && c <= 90)
        {
            c += 32;
        }

        if (_unicodeCharacters == null)
        {
            return null;
        }
        return _unicodeCharacters.get(c);
    }

    public void output()
    {
        System.out.println("Please implement a output method for GazetteerTrieSmallNode");
    }
}