/* * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.lang.model.type; import javax.lang.model.element.*; /** * A visitor of types, in the style of the * visitor design pattern. Classes implementing this * interface are used to operate on a type when the kind of * type is unknown at compile time. When a visitor is passed to a * type's {@link TypeMirror#accept accept} method, the visitXYZ * method most applicable to that type is invoked. * *
Classes implementing this interface may or may not throw a * {@code NullPointerException} if the additional parameter {@code p} * is {@code null}; see documentation of the implementing class for * details. * *
WARNING: It is possible that methods will be added to
* this interface to accommodate new, currently unknown, language
* structures added to future versions of the Java™ programming
* language. Therefore, visitor classes directly implementing this
* interface may be source incompatible with future versions of the
* platform. To avoid this source incompatibility, visitor
* implementations are encouraged to instead extend the appropriate
* abstract visitor class that implements this interface. However, an
* API should generally use this visitor interface as the type for
* parameters, return type, etc. rather than one of the abstract
* classes.
*
* @param the type of the additional parameter to this visitor's
* methods. Use {@code Void} for visitors that do not need an
* additional parameter.
*
* @author Joseph D. Darcy
* @author Scott Seligman
* @author Peter von der Ahé
* @since 1.6
*/
public interface TypeVisitor