code: package it.unibz.inf.ontop.utils;
  
  /*
   * #%L
   * ontop-obdalib-core
   * %%
   * Copyright (C) 2009 - 2014 Free University of Bozen-Bolzano
   * %%
   * 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.
   * #L%
   */
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Properties;
  
  public class VersionInfo {
  	
  	private static VersionInfo instance;
  
  	private String version;
  
  	private VersionInfo() {
      	try (InputStream inputStream = VersionInfo.class.getResourceAsStream("/version.properties")) {
              // Load the properties file
  			Properties prop = new Properties();
      		prop.load(inputStream);
              // Get the property value
              version = prop.getProperty("version");
      	}
      	catch (IOException ex) {
      		ex.printStackTrace();
          }
  	}
  
  	public synchronized static VersionInfo getVersionInfo() {
  		if (instance == null) {
  			instance = new VersionInfo();
  		}
  		return instance;
  	}
  
  	/**
  	 * Gets a string that contains the version of this build. This is generated
  	 * from the manifest of the jar that this class is packaged in.
  	 * 
  	 * @return The version info string (if available).
  	 */
  	public String getVersion() {
          // the following does not work in IDEs
          // return getClass().getPackage().getImplementationVersion();
  		return  version;
  	}
  	
  	@Override
  	public String toString() {
  		return version;
  	}
  }
  