https://tomcat.apache.org/: JSP package 
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
package javax.servlet.jsp.tagext;


Serves as a base class for Tag and SimpleTag.
This is mostly for organizational and type-safety purposes.

Since:2.0
/**
 * Serves as a base class for Tag and SimpleTag.
 * This is mostly for organizational and type-safety purposes.
 *
 * @since 2.0
 */
public interface JspTag {
    // No methods even through there are some common methods
}