code: private static TokenizerEngine doCreate() {
  		try {
  			return new AnsjEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new HanLPEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new IKAnalyzerEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new JcsegEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new JiebaEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new MmsegEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new WordEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		try {
  			return new SmartcnEngine();
  		} catch (NoClassDefFoundError e) {
  			// ignore
  		}
  		throw new TokenizerException("No tokenizer found ! Please add some tokenizer jar to your project !");
  	}
docs: 根据用户引入的分词引擎jar，自动创建对应的分词引擎对象
  
  @return {@link TokenizerEngine}