1 /* 2 * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Sun designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Sun in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 22 * CA 95054 USA or visit www.sun.com if you need additional information or 23 * have any questions. 24 */ 25 26 package com.sun.mirror.util; 27 28 /** 29 * Utilities to create specialized <tt>DeclarationVisitor</tt> instances. 30 * 31 * @author Joseph D. Darcy 32 * @author Scott Seligman 33 * @since 1.5 34 */ 35 public class DeclarationVisitors { 36 private DeclarationVisitors(){} // do not instantiate. 37 38 /** 39 * A visitor that has no side effects and keeps no state. 40 */ 41 public static final DeclarationVisitor NO_OP = new SimpleDeclarationVisitor(); 42 43 /** 44 * Return a <tt>DeclarationVisitor</tt> that will scan the 45 * declaration structure, visiting declarations contained in 46 * another declaration. For example, when visiting a class, the 47 * fields, methods, constructors, etc. of the class are also 48 * visited. The order in which the contained declarations are scanned is 49 * not specified. 50 * 51 * <p>The <tt>pre</tt> and <tt>post</tt> 52 * <tt>DeclarationVisitor</tt> parameters specify, 53 * respectively, the processing the scanner will do before or 54 * after visiting the contained declarations. If only one of pre 55 * and post processing is needed, use {@link 56 * DeclarationVisitors#NO_OP DeclarationVisitors.NO_OP} for the 57 * other parameter. 58 * 59 * @param pre visitor representing processing to do before 60 * visiting contained declarations. 61 * 62 * @param post visitor representing processing to do after 63 * visiting contained declarations. 64 */ 65 public static DeclarationVisitor getDeclarationScanner(DeclarationVisitor pre, 66 DeclarationVisitor post) { 67 return new DeclarationScanner(pre, post); 68 } 69 70 /** 71 * Return a <tt>DeclarationVisitor</tt> that will scan the 72 * declaration structure, visiting declarations contained in 73 * another declaration in source code order. For example, when 74 * visiting a class, the fields, methods, constructors, etc. of 75 * the class are also visited. The order in which the contained 76 * declarations are visited is as close to source code order as 77 * possible; declaration mirrors created from class files instead 78 * of source code will not have source position information. 79 * 80 * <p>The <tt>pre</tt> and <tt>post</tt> 81 * <tt>DeclarationVisitor</tt> parameters specify, 82 * respectively, the processing the scanner will do before or 83 * after visiting the contained declarations. If only one of pre 84 * and post processing is needed, use {@link 85 * DeclarationVisitors#NO_OP DeclarationVisitors.NO_OP} for the other parameter. 86 * 87 * @param pre visitor representing processing to do before 88 * visiting contained declarations. 89 * 90 * @param post visitor representing processing to do after 91 * visiting contained declarations. 92 */ 93 public static DeclarationVisitor getSourceOrderDeclarationScanner(DeclarationVisitor pre, 94 DeclarationVisitor post) { 95 return new SourceOrderDeclScanner(pre, post); 96 } 97 }