1 package net.sourceforge.jenesis4java;
2
3 /*
4 * #%L
5 * Jenesis 4 Java Code Generator
6 * %%
7 * Copyright (C) 2000 - 2016 jenesis4java
8 * %%
9 * This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as
11 * published by the Free Software Foundation, either version 3 of the
12 * License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Lesser Public License for more details.
18 *
19 * You should have received a copy of the GNU General Lesser Public
20 * License along with this program. If not, see
21 * <http://www.gnu.org/licenses/lgpl-3.0.html>.
22 * #L%
23 */
24
25 /**
26 * Base implementation for a visitor that goes as deep as desired.
27 * <p>
28 * Traversal is done in pre-order.
29 */
30 public abstract class ConditionalVisitor implements ReplacingVisitor {
31
32 @Override
33 public final Codeable visitReplace(Codeable current, Codeable parent) {
34 if (current != null) {
35 boolean traverseFurther = visit(current, parent);
36 if (traverseFurther) {
37 current.visit(this);
38 }
39 }
40 return current;
41 }
42
43 /**
44 * This method is called for each non-{@code null} Codeable.
45 *
46 * @param current
47 * The currently visited Codeable. This is never {@code null}.
48 * @param parent
49 * The parent of the visited Codeable. This is never {@code null}
50 * .
51 * @return {@code true}, if the visitor is to visit the children of the
52 * current node, {@code false}, if not.
53 */
54 public abstract boolean visit(Codeable current, Codeable parent);
55
56 }