PatternSearchTrie.java

package com.learn.tree;

import java.util.Map;
import java.util.Set;

public class PatternSearchTrie {
	
	static Trie root;

	public static void main(String[] args) {
		// TODO Auto-generated method stub
    String[] words = {"beb","black","amateur","zen","aman"};
    PatternSearchTrie pt = new PatternSearchTrie();
    	for (String s: words)
    	{
    		pt.add(s);
    	}
    	pt.traverse(root.list);
    System.out.println(pt.find("zena"));
	}
	
	public void traverse(Map<Character,Trie> list)
	{
		Set<Character> keys = list.keySet();
		if(keys.isEmpty())
			return;
		for(Character key : keys)
		{
			System.out.println(key);
			traverse(list.get(key).list);
		}
	}
	
	public void add(String s)
	{
		if(root == null)
		{
			Trie newnode = new Trie((char)0);
			root = newnode;
		}
		char[] str = s.toCharArray();
		int length = str.length;
		Trie currentnode = root;
		for(int i=0;i<length;i++)
		{
		 if(currentnode.list.containsKey(str[i]))
		 {
			 currentnode = currentnode.list.get(str[i]);				 
		 }
		 else
		 {
			 Trie newnode = new Trie(str[i]);
			 currentnode.list.put(str[i], newnode);
			 currentnode = newnode;
		 }
		}
		currentnode.word=true;
	}
	
	public boolean find(String str)
	{
		int length = str.length();
		char[] array = str.toCharArray();
		Trie currentnode = root;
		for(int i=0;i<length;i++)
		{
			if(currentnode.list.containsKey(array[i]))
				currentnode = currentnode.list.get(array[i]);
			else
				return false;
		}
		return true;
	}

}