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1   /***
2    *
3    * Copyright 2005 Jeremy Rayner
4    *
5    * Licensed under the Apache License, Version 2.0 (the "License");
6    * you may not use this file except in compliance with the License.
7    * You may obtain a copy of the License at
8    *
9    * http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   *
17   **/
18  package org.codehaus.groovy.antlr.treewalker;
19  
20  import java.util.ArrayList;
21  import java.util.Collections;
22  
23  import org.codehaus.groovy.antlr.GroovySourceAST;
24  import org.codehaus.groovy.antlr.parser.GroovyTokenTypes;
25  
26  /***
27   * A treewalker for the antlr generated AST that attempts to visit the
28   * AST nodes in the order needed to generate valid groovy source code.
29   *
30   * @author <a href="mailto:groovy@ross-rayner.com">Jeremy Rayner</a>
31   * @version $Revision: 4538 $
32   */
33  public class SourceCodeTraversal extends TraversalHelper {
34      /***
35       * Constructs a treewalker for the antlr generated AST that attempts to visit the
36       * AST nodes in the order needed to generate valid groovy source code.
37       * @param visitor the visitor implementation to call for each AST node.
38       */
39      public SourceCodeTraversal(Visitor visitor) {
40          super(visitor);
41      }
42  
43      /***
44       * gather, sort and process all unvisited nodes
45       * @param t the AST to process
46       */
47      public void setUp(GroovySourceAST t) {
48          super.setUp(t);
49          
50          // gather and sort all unvisited AST nodes
51          unvisitedNodes = new ArrayList();
52          traverse((GroovySourceAST)t);
53          Collections.sort(unvisitedNodes);
54      }
55  
56      /***
57       * traverse an AST node
58       * @param t the AST node to traverse
59       */
60      private void traverse(GroovySourceAST t) {
61          if (t == null) { return; }
62          if (unvisitedNodes != null) {
63             unvisitedNodes.add(t);
64          }
65          GroovySourceAST child = (GroovySourceAST)t.getFirstChild();
66          if (child != null) {
67              traverse(child);
68          }
69          GroovySourceAST sibling = (GroovySourceAST)t.getNextSibling();
70          if (sibling != null) {
71              traverse(sibling);
72          }
73      }
74  
75      protected void accept(GroovySourceAST currentNode) {
76          if (currentNode != null && unvisitedNodes != null && unvisitedNodes.size() > 0) {
77              GroovySourceAST t = currentNode;
78  
79              if (!(unvisitedNodes.contains(currentNode))) {
80                  return;
81              }
82              push(t);
83              switch (t.getType()) {
84                  case GroovyTokenTypes.QUESTION: // expr?foo:bar
85                      accept_FirstChild_v_SecondChild_v_ThirdChild_v(t);
86                      break;
87  
88                  case GroovyTokenTypes.CASE_GROUP: //
89                  case GroovyTokenTypes.LITERAL_instanceof: // foo instanceof MyType
90                      accept_FirstChild_v_SecondChildsChildren_v(t);
91                      break;
92  
93                  case GroovyTokenTypes.ANNOTATION:
94                      accept_v_FirstChild_2ndv_SecondChild_v___LastChild_v(t);
95                      break;
96  
97                  case GroovyTokenTypes.ELIST: // a,b,c
98                  case GroovyTokenTypes.PARAMETERS: // a,b,c
99                  case GroovyTokenTypes.TYPE_ARGUMENTS: // <String, Object>
100                 case GroovyTokenTypes.STRING_CONSTRUCTOR: // "foo${bar}wibble"
101                 case GroovyTokenTypes.TYPE_PARAMETER: // class Foo<T extends F>
102                 case GroovyTokenTypes.TYPE_PARAMETERS: // class Foo<T>
103                 case GroovyTokenTypes.TYPE_UPPER_BOUNDS: // class Foo<T extends F>
104                     accept_v_FirstChild_v_SecondChild_v___LastChild_v(t);
105                     // todo : confirm that TYPE_LOWER_BOUNDS does not have multiple children
106                     break;
107 
108                 case GroovyTokenTypes.VARIABLE_PARAMETER_DEF: // void f(String ... others) {}
109                     accept_v_FirstChild_SecondChild_v_ThirdChild_v(t);
110                     break;
111 
112                 case GroovyTokenTypes.INDEX_OP:
113                     accept_FirstChild_v_SecondChild_v(t);
114                     break;
115 
116                 case GroovyTokenTypes.ENUM_CONSTANT_DEF: // enum Foo(THESE,ARE,THEY)
117                 case GroovyTokenTypes.EXPR:
118                 case GroovyTokenTypes.IMPORT:
119                 case GroovyTokenTypes.VARIABLE_DEF:
120                 case GroovyTokenTypes.METHOD_DEF:
121                 case GroovyTokenTypes.OBJBLOCK: //class Foo {def bar()}  <-- this block
122                 case GroovyTokenTypes.PARAMETER_DEF: // void f(String me) {}
123                 case GroovyTokenTypes.SLIST: // list of expressions, variable defs etc
124                     accept_v_AllChildren_v(t);
125                     break;
126 
127                 case GroovyTokenTypes.ANNOTATION_MEMBER_VALUE_PAIR: // @Blue(foo=123)
128                 case GroovyTokenTypes.ASSIGN: // a = b
129                 case GroovyTokenTypes.BAND_ASSIGN: // a &= b
130                 case GroovyTokenTypes.BOR_ASSIGN: // a |= b
131                 case GroovyTokenTypes.BSR_ASSIGN: // a >>>= b
132                 case GroovyTokenTypes.BXOR_ASSIGN: // a ^= b
133                 case GroovyTokenTypes.COMPARE_TO: // a <=> b
134                 case GroovyTokenTypes.DIV_ASSIGN: // a /= b
135                 case GroovyTokenTypes.EQUAL: // a == b
136                 case GroovyTokenTypes.MINUS_ASSIGN: // a -= b
137                 case GroovyTokenTypes.MOD_ASSIGN: // a %= b
138                 case GroovyTokenTypes.NOT_EQUAL: // a != b
139                 case GroovyTokenTypes.PLUS_ASSIGN: // a += b
140                 case GroovyTokenTypes.REGEX_FIND: // a =~ b
141                 case GroovyTokenTypes.REGEX_MATCH: // a ==~ b
142                 case GroovyTokenTypes.SL_ASSIGN: // a <<= b
143                 case GroovyTokenTypes.SR_ASSIGN: // a >>= b
144                 case GroovyTokenTypes.STAR_ASSIGN: // a *= b
145                 case GroovyTokenTypes.STAR_STAR_ASSIGN: // x **= 3
146                     if (t.childAt(1) != null) {
147                         accept_FirstChild_v_RestOfTheChildren(t);
148                     } else {
149                         accept_v_FirstChild_v_RestOfTheChildren(t);
150                     }
151                     break;
152 
153                 case GroovyTokenTypes.ANNOTATION_FIELD_DEF: // @interface Foo{ int bar()...
154                     accept_FirstSecondAndThirdChild_v_v_ForthChild(t);
155                     break;
156                     
157                 case GroovyTokenTypes.ANNOTATION_DEF: // @interface Foo...
158                 case GroovyTokenTypes.BAND: // 1 & 2
159                 case GroovyTokenTypes.BOR: // 1 | 2
160                 case GroovyTokenTypes.BSR: // 1 >>> 2
161                 case GroovyTokenTypes.BXOR: // 1 ^ 2
162                 case GroovyTokenTypes.CLASS_DEF: // class Foo...
163                 case GroovyTokenTypes.CTOR_IDENT: // private Foo() {...
164                 case GroovyTokenTypes.DIV: //  3/4
165                 case GroovyTokenTypes.DOT: // foo.bar
166                 case GroovyTokenTypes.ENUM_DEF: // enum Foo...
167                 case GroovyTokenTypes.GE: // a >= b
168                 case GroovyTokenTypes.GT: // a > b
169                 case GroovyTokenTypes.INTERFACE_DEF: // interface Foo...
170                 case GroovyTokenTypes.LABELED_ARG: // myMethod(name:"Jez")
171                 case GroovyTokenTypes.LABELED_STAT: // foo:x=1                    	
172                 case GroovyTokenTypes.LAND: // true && false
173                 case GroovyTokenTypes.LE: // a <= b
174                 case GroovyTokenTypes.LITERAL_as: // foo as Bar
175                 case GroovyTokenTypes.LITERAL_in: // if (i in myList) ...
176                 case GroovyTokenTypes.LOR: // true && false
177                 case GroovyTokenTypes.LT: // a < b
178                 case GroovyTokenTypes.MEMBER_POINTER: // this.&foo()
179                 case GroovyTokenTypes.MOD: //  4 % 3
180                 case GroovyTokenTypes.MINUS: // 1 - 1
181                 case GroovyTokenTypes.OPTIONAL_DOT: // foo?.bar
182                 case GroovyTokenTypes.PACKAGE_DEF:
183                 case GroovyTokenTypes.PLUS: // 1 + 1
184                 case GroovyTokenTypes.RANGE_EXCLUSIVE: // [1..<10]
185                 case GroovyTokenTypes.RANGE_INCLUSIVE: // [1..10]
186                 case GroovyTokenTypes.SL: // a << b
187                 case GroovyTokenTypes.SR: // a >> b
188                 case GroovyTokenTypes.STAR: // a * b   or    import foo.*
189                 case GroovyTokenTypes.STAR_STAR: // x ** 3
190                     accept_FirstChild_v_RestOfTheChildren(t);
191                     break;
192 
193                 case GroovyTokenTypes.CTOR_CALL:
194                 case GroovyTokenTypes.METHOD_CALL:
195                     if (t.getNumberOfChildren() == 2 && t.childAt(1) != null && t.childAt(1).getType() == GroovyTokenTypes.CLOSABLE_BLOCK) {
196                         // myMethod {...
197                         accept_FirstChild_v_SecondChild(t);
198                     } else {
199                         GroovySourceAST lastChild = t.childAt(t.getNumberOfChildren() -1);
200                         if (lastChild != null && lastChild.getType() == GroovyTokenTypes.CLOSABLE_BLOCK) {
201                             // myMethod(a,b) {...
202                             accept_FirstChild_v_RestOfTheChildren_v_LastChild(t);
203                         } else {
204                             // myMethod(a,b)
205                             accept_FirstChild_v_RestOfTheChildren_v(t);
206                         }
207                     }
208                     break;
209 
210                 case GroovyTokenTypes.LITERAL_while:
211                 case GroovyTokenTypes.LITERAL_with:
212                 case GroovyTokenTypes.TYPECAST: // (String)itr.next()
213                     accept_v_FirstChildsFirstChild_v_RestOfTheChildren(t);
214                     break;
215 
216                 case GroovyTokenTypes.LITERAL_if: // if (grandchild) {child1} else {child2} ...
217                     accept_v_FirstChildsFirstChild_v_Child2_Child3_v_Child4_v___v_LastChild(t);
218                     break;
219 
220                 case GroovyTokenTypes.CLOSABLE_BLOCK: // [1,2,3].each {foo(it)}  <-- Closure
221                     if (t.childAt(0) != null && t.childAt(0).getType() == GroovyTokenTypes.IMPLICIT_PARAMETERS) {
222                         accept_v_AllChildren_v(t);
223                     } else {
224                         accept_v_FirstChild_v_RestOfTheChildren_v(t);
225                     }
226                     break;
227 
228                 case GroovyTokenTypes.FOR_IN_ITERABLE:
229                 case GroovyTokenTypes.LITERAL_for:
230                 case GroovyTokenTypes.LITERAL_new:
231                 case GroovyTokenTypes.LITERAL_switch:
232                     accept_v_FirstChild_v_RestOfTheChildren_v(t);
233                     break;
234  
235                 case GroovyTokenTypes.ANNOTATIONS: // just like modifiers but for package/enum declarations
236                 case GroovyTokenTypes.LITERAL_assert:
237                 case GroovyTokenTypes.LITERAL_catch:
238                 case GroovyTokenTypes.LITERAL_synchronized:
239                 case GroovyTokenTypes.LITERAL_try:
240                 case GroovyTokenTypes.MODIFIERS:
241                     accept_v_FirstChild_v_RestOfTheChildren(t);
242                     break;
243 
244                 default:
245                     accept_v_FirstChild_v(t);
246                     break;
247             }
248             pop();
249         }
250     }
251 }