JWS Task 2: Raw XML and Levenshtein distance

Vladimir Levenshtein

Example Solution

Service Endpoint Interface

package com.fuzilaga.jws.levenshtein;

import javax.jws.WebMethod;
import javax.jws.WebService;
import javax.jws.soap.SOAPBinding;
import javax.jws.soap.SOAPBinding.Style;

@WebService
@SOAPBinding(style=Style.RPC)
public interface LevenshteinService
{
	@WebMethod
	public int levenshteinDistance(String s[]);
}

Service Implementation Bean

package com.fuzilaga.jws.levenshtein;

import javax.jws.WebService;

@WebService(endpointInterface = "com.fuzilaga.jws.levenshtein.LevenshteinService")
public class LevenshteinServiceImpl implements LevenshteinService
{

	public int levenshteinDistance(String s[])
	{
		String s1 = s[0];
		String s2 = s[1];
		if (null == s1 || null == s2)
		{
			return -1;
		}

		int s1len = s1.length();
		int s2len = s2.length();
		int i = 0, j = 0, cost = 0;
		char s1i, s2j;
		int matrix[][] = new int[s1len + 1][s2len + 1];

		for (i = 0; i <= s1len; i++)
		{
			matrix[i][0] = i; // deletion
		}
		for (j = 0; j <= s2len; j++)
		{
			matrix[0][j] = j; // insertion
		}

		for (i = 1; i <= s1len; i++)
		{
			s1i = s1.charAt(i - 1);
			for (j = 1; j <= s2len; j++)
			{
				s2j = s2.charAt(j - 1);
				if (s1i == s2j)
				{
					cost = 0;
				} else
				{
					cost = 1;
				}
				matrix[i][j] = min(matrix[i - 1][j] + 1, // deletion
						matrix[i][j - 1] + 1, // insertion
						matrix[i - 1][j - 1] + cost // substitution
				);
			}
		}

		return matrix[s1len][s2len];
	}

	private int min(int a, int b, int c)
	{
		int min = a;
		if (b < min)
		{
			min = b;
		}
		if (c < min)
		{
			min = c;
		}
		return min;
	}
}

Service Publisher

package com.fuzilaga.jws.levenshtein;

import javax.xml.ws.Endpoint;

public class LevenshteinServicePublisher
{
	public static void main(String args[])
	{
		Endpoint.publish("http://localhost:8880/levenshtein", new LevenshteinServiceImpl());
	}
}

Service Client

package com.fuzilaga.jws.levenshtein;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class LevenshteinClient
{
	public static void main(String args[]) throws Exception
	{
		StringBuilder msg = new StringBuilder();
		msg.append("<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:lev=\"http://levenshtein.jws.fuzilaga.com/\">");
		msg.append("	<soapenv:Header/>");
		msg.append("	<soapenv:Body>");
		msg.append("		<lev:levenshteinDistance>");
		msg.append("			<arg0>");
		msg.append("				<item>kitten</item>");
		msg.append("				<item>sitting</item>");
		msg.append("			</arg0>");
		msg.append("		</lev:levenshteinDistance>");
		msg.append("	</soapenv:Body>");
		msg.append("</soapenv:Envelope>");

		// get connection
		URL url = new URL("http://localhost:8880/levenshtein");
		HttpURLConnection conn = (HttpURLConnection) url.openConnection();
		conn.setRequestMethod("POST");
		conn.setRequestProperty("Content-Type", "text/xml");
		conn.setRequestProperty("accept", "text/xml");
		conn.setDoInput(true);
		conn.setDoOutput(true);

		// send
		DataOutputStream writer = new DataOutputStream(conn.getOutputStream());
		writer.writeBytes(msg.toString());
		writer.flush();

		// read
		BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
		StringBuilder response = new StringBuilder();
		String next = "";
		while ((next = reader.readLine()) != null)
		{
			response.append(next);
		}

		writer.close();
	    reader.close();

		System.out.println("response = " + response.toString());
	}
}

NOTE: Full source and instructions on how to run locally can be found here.