字典树的插入、查询、前缀查询、模糊查询

package jjd;

import java.util.TreeMap;

public class Trie {
	public class Node {
		private boolean isWord;
		private TreeMap<Character, Node> next;

		public Node(boolean isWord) {
			this.isWord = isWord;
			next = new TreeMap<>();
		}

		public Node() {
			this.isWord = false;
			next = new TreeMap<>();
		}

	}

	private Node root;
	private int size;

	public Trie() {
		root = new Node();
		size = 0;
	}

	public int getSize() {
		return size;
	}

	public void add(String word) {
		Node cur = root;
		for (int i = 0; i < word.length(); i++) {
			char c = word.charAt(i);
			if (cur.next.get(c) == null) {
				cur.next.put(c, new Node());
			}
			cur = cur.next.get(c);
		}
		if (!cur.isWord) {
			cur.isWord = true;
			size++;
		}
	}

	public boolean contains(String word) {
		Node cur = root;
		for (int i = 0; i < word.length(); i++) {
			char c = word.charAt(i);
			if (cur.next.get(c) == null) {
				return false;
			}
			cur = cur.next.get(c);
		}
		return cur.isWord;
	}

	public boolean prefix(String word) {
		Node cur = root;
		for (int i = 0; i < word.length(); i++) {
			char c = word.charAt(i);
			if (cur.next.get(c) == null) {
				return false;
			}
			cur = cur.next.get(c);
		}
		return true;
	}
	public boolean search(String word) {
		return match(root,word,0);
	}

	private boolean match(Node node, String word, int index) {
		if(index==word.length())return node.isWord;
		char c=word.charAt(index);
		if(c!='.') {
			if(node.next.get(c)==null) {
				return false;
			}
			return match(node.next.get(c),word,index+1);
		}else {
			for(char nextChar:node.next.keySet()) {
				if(match(node.next.get(nextChar),word,index+1))
					return true;
			}
			return false;
		}
	}
}