aoqi@0: /*
aoqi@0: * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0: *
aoqi@0: * This code is free software; you can redistribute it and/or modify it
aoqi@0: * under the terms of the GNU General Public License version 2 only, as
aoqi@0: * published by the Free Software Foundation. Oracle designates this
aoqi@0: * particular file as subject to the "Classpath" exception as provided
aoqi@0: * by Oracle in the LICENSE file that accompanied this code.
aoqi@0: *
aoqi@0: * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
aoqi@0: * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0: * accompanied this code).
aoqi@0: *
aoqi@0: * You should have received a copy of the GNU General Public License version
aoqi@0: * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0: *
aoqi@0: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0: * or visit www.oracle.com if you need additional information or have any
aoqi@0: * questions.
aoqi@0: */
aoqi@0:
aoqi@0: package javax.lang.model.util;
aoqi@0:
aoqi@0: import javax.annotation.processing.SupportedSourceVersion;
aoqi@0: import javax.lang.model.SourceVersion;
aoqi@0: import javax.lang.model.element.*;
aoqi@0: import static javax.lang.model.SourceVersion.*;
aoqi@0:
aoqi@0:
aoqi@0: /**
aoqi@0: * A skeletal visitor of program elements with default behavior
aoqi@0: * appropriate for the {@link SourceVersion#RELEASE_6 RELEASE_6}
aoqi@0: * source version.
aoqi@0: *
aoqi@0: * WARNING: The {@code ElementVisitor} interface
aoqi@0: * implemented by this class may have methods added to it in the
aoqi@0: * future to accommodate new, currently unknown, language structures
aoqi@0: * added to future versions of the Java™ programming language.
aoqi@0: * Therefore, methods whose names begin with {@code "visit"} may be
aoqi@0: * added to this class in the future; to avoid incompatibilities,
aoqi@0: * classes which extend this class should not declare any instance
aoqi@0: * methods with names beginning with {@code "visit"}.
aoqi@0: *
aoqi@0: *
When such a new visit method is added, the default
aoqi@0: * implementation in this class will be to call the {@link
aoqi@0: * #visitUnknown visitUnknown} method. A new abstract element visitor
aoqi@0: * class will also be introduced to correspond to the new language
aoqi@0: * level; this visitor will have different default behavior for the
aoqi@0: * visit method in question. When the new visitor is introduced, all
aoqi@0: * or portions of this visitor may be deprecated.
aoqi@0: *
aoqi@0: *
Note that adding a default implementation of a new visit method
aoqi@0: * in a visitor class will occur instead of adding a default
aoqi@0: * method directly in the visitor interface since a Java SE 8
aoqi@0: * language feature cannot be used to this version of the API since
aoqi@0: * this version is required to be runnable on Java SE 7
aoqi@0: * implementations. Future versions of the API that are only required
aoqi@0: * to run on Java SE 8 and later may take advantage of default methods
aoqi@0: * in this situation.
aoqi@0: *
aoqi@0: * @param the return type of this visitor's methods. Use {@link
aoqi@0: * Void} for visitors that do not need to return results.
aoqi@0: * @param the type of the additional parameter to this visitor's
aoqi@0: * methods. Use {@code Void} for visitors that do not need an
aoqi@0: * additional parameter.
aoqi@0: *
aoqi@0: * @author Joseph D. Darcy
aoqi@0: * @author Scott Seligman
aoqi@0: * @author Peter von der Ahé
aoqi@0: *
aoqi@0: * @see AbstractElementVisitor7
aoqi@0: * @see AbstractElementVisitor8
aoqi@0: * @since 1.6
aoqi@0: */
aoqi@0: @SupportedSourceVersion(RELEASE_6)
aoqi@0: public abstract class AbstractElementVisitor6 implements ElementVisitor {
aoqi@0: /**
aoqi@0: * Constructor for concrete subclasses to call.
aoqi@0: */
aoqi@0: protected AbstractElementVisitor6(){}
aoqi@0:
aoqi@0: /**
aoqi@0: * Visits any program element as if by passing itself to that
aoqi@0: * element's {@link Element#accept accept} method. The invocation
aoqi@0: * {@code v.visit(elem)} is equivalent to {@code elem.accept(v,
aoqi@0: * p)}.
aoqi@0: *
aoqi@0: * @param e the element to visit
aoqi@0: * @param p a visitor-specified parameter
aoqi@0: * @return a visitor-specified result
aoqi@0: */
aoqi@0: public final R visit(Element e, P p) {
aoqi@0: return e.accept(this, p);
aoqi@0: }
aoqi@0:
aoqi@0: /**
aoqi@0: * Visits any program element as if by passing itself to that
aoqi@0: * element's {@link Element#accept accept} method and passing
aoqi@0: * {@code null} for the additional parameter. The invocation
aoqi@0: * {@code v.visit(elem)} is equivalent to {@code elem.accept(v,
aoqi@0: * null)}.
aoqi@0: *
aoqi@0: * @param e the element to visit
aoqi@0: * @return a visitor-specified result
aoqi@0: */
aoqi@0: public final R visit(Element e) {
aoqi@0: return e.accept(this, null);
aoqi@0: }
aoqi@0:
aoqi@0: /**
aoqi@0: * {@inheritDoc}
aoqi@0: *
aoqi@0: * The default implementation of this method in
aoqi@0: * {@code AbstractElementVisitor6} will always throw
aoqi@0: * {@code UnknownElementException}.
aoqi@0: * This behavior is not required of a subclass.
aoqi@0: *
aoqi@0: * @param e the element to visit
aoqi@0: * @param p a visitor-specified parameter
aoqi@0: * @return a visitor-specified result
aoqi@0: * @throws UnknownElementException
aoqi@0: * a visitor implementation may optionally throw this exception
aoqi@0: */
aoqi@0: public R visitUnknown(Element e, P p) {
aoqi@0: throw new UnknownElementException(e, p);
aoqi@0: }
aoqi@0: }