darcy@1054: /*
jjg@1357: * Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
darcy@1054: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
darcy@1054: *
darcy@1054: * This code is free software; you can redistribute it and/or modify it
darcy@1054: * under the terms of the GNU General Public License version 2 only, as
darcy@1054: * published by the Free Software Foundation. Oracle designates this
darcy@1054: * particular file as subject to the "Classpath" exception as provided
darcy@1054: * by Oracle in the LICENSE file that accompanied this code.
darcy@1054: *
darcy@1054: * This code is distributed in the hope that it will be useful, but WITHOUT
darcy@1054: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
darcy@1054: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
darcy@1054: * version 2 for more details (a copy is included in the LICENSE file that
darcy@1054: * accompanied this code).
darcy@1054: *
darcy@1054: * You should have received a copy of the GNU General Public License version
darcy@1054: * 2 along with this work; if not, write to the Free Software Foundation,
darcy@1054: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
darcy@1054: *
darcy@1054: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
darcy@1054: * or visit www.oracle.com if you need additional information or have any
darcy@1054: * questions.
darcy@1054: */
darcy@1054:
darcy@1054: package javax.lang.model.util;
darcy@1054:
darcy@1054: import javax.lang.model.element.*;
darcy@1054: import javax.annotation.processing.SupportedSourceVersion;
darcy@1054: import javax.lang.model.SourceVersion;
darcy@1054: import static javax.lang.model.SourceVersion.*;
darcy@1054:
darcy@1054:
darcy@1054: /**
darcy@1054: * A scanning visitor of program elements with default behavior
darcy@1054: * appropriate for the {@link SourceVersion#RELEASE_8 RELEASE_8}
darcy@1054: * source version. The visitXYZ methods in this
darcy@1054: * class scan their component elements by calling {@code scan} on
darcy@1054: * their {@linkplain Element#getEnclosedElements enclosed elements},
darcy@1054: * {@linkplain ExecutableElement#getParameters parameters}, etc., as
darcy@1054: * indicated in the individual method specifications. A subclass can
darcy@1054: * control the order elements are visited by overriding the
darcy@1054: * visitXYZ methods. Note that clients of a scanner
darcy@1054: * may get the desired behavior be invoking {@code v.scan(e, p)} rather
darcy@1054: * than {@code v.visit(e, p)} on the root objects of interest.
darcy@1054: *
darcy@1054: * When a subclass overrides a visitXYZ method, the
darcy@1054: * new method can cause the enclosed elements to be scanned in the
darcy@1054: * default way by calling super.visitXYZ. In this
darcy@1054: * fashion, the concrete visitor can control the ordering of traversal
darcy@1054: * over the component elements with respect to the additional
darcy@1054: * processing; for example, consistently calling
darcy@1054: * super.visitXYZ at the start of the overridden
darcy@1054: * methods will yield a preorder traversal, etc. If the component
darcy@1054: * elements should be traversed in some other order, instead of
darcy@1054: * calling super.visitXYZ, an overriding visit method
darcy@1054: * should call {@code scan} with the elements in the desired order.
darcy@1054: *
darcy@1054: *
Methods in this class may be overridden subject to their
darcy@1054: * general contract. Note that annotating methods in concrete
darcy@1054: * subclasses with {@link java.lang.Override @Override} will help
darcy@1054: * ensure that methods are overridden as intended.
darcy@1054: *
darcy@1054: *
WARNING: The {@code ElementVisitor} interface
darcy@1054: * implemented by this class may have methods added to it in the
darcy@1054: * future to accommodate new, currently unknown, language structures
darcy@1054: * added to future versions of the Java™ programming language.
darcy@1054: * Therefore, methods whose names begin with {@code "visit"} may be
darcy@1054: * added to this class in the future; to avoid incompatibilities,
darcy@1054: * classes which extend this class should not declare any instance
darcy@1054: * methods with names beginning with {@code "visit"}.
darcy@1054: *
darcy@1054: *
When such a new visit method is added, the default
darcy@1054: * implementation in this class will be to call the {@link
darcy@1054: * #visitUnknown visitUnknown} method. A new element scanner visitor
darcy@1054: * class will also be introduced to correspond to the new language
darcy@1054: * level; this visitor will have different default behavior for the
darcy@1054: * visit method in question. When the new visitor is introduced, all
darcy@1054: * or portions of this visitor may be deprecated.
darcy@1054: *
darcy@1054: * @param the return type of this visitor's methods. Use {@link
darcy@1054: * Void} for visitors that do not need to return results.
darcy@1054: * @param the type of the additional parameter to this visitor's
darcy@1054: * methods. Use {@code Void} for visitors that do not need an
darcy@1054: * additional parameter.
darcy@1054: *
darcy@1054: * @see ElementScanner6
darcy@1054: * @see ElementScanner7
darcy@1054: * @since 1.8
darcy@1054: */
darcy@1054: @SupportedSourceVersion(RELEASE_8)
darcy@1054: public class ElementScanner8 extends ElementScanner7 {
darcy@1054: /**
darcy@1054: * Constructor for concrete subclasses; uses {@code null} for the
darcy@1054: * default value.
darcy@1054: */
darcy@1054: protected ElementScanner8(){
darcy@1054: super(null);
darcy@1054: }
darcy@1054:
darcy@1054: /**
darcy@1054: * Constructor for concrete subclasses; uses the argument for the
darcy@1054: * default value.
darcy@1054: */
darcy@1054: protected ElementScanner8(R defaultValue){
darcy@1054: super(defaultValue);
darcy@1054: }
darcy@1054: }