1 /*
2 * Copyright 2003-2007 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.codehaus.groovy.antlr;
18
19 /**
20 * Process to decorate antlr AST with ending line/col info, and if
21 * possible the snipppet of source from the start/end line/col for each node.
22 *
23 * @author <a href="mailto:groovy@ross-rayner.com">Jeremy Rayner</a>
24 * @version $Revision: 21223 $
25 */
26
27 import antlr.collections.AST;
28 import java.util.*;
29
30 public class AntlrASTProcessSnippets implements AntlrASTProcessor{
31
32 public AntlrASTProcessSnippets() {
33 }
34
35 /**
36 * decorate antlr AST with ending line/col info, and if
37 * possible the snipppet of source from the start/end line/col for each node.
38 * @param t the AST to decorate
39 * @return the decorated AST
40 */
41 public AST process(AST t) {
42 // first visit
43 List l = new ArrayList();
44 traverse((GroovySourceAST)t,l,null);
45
46 //System.out.println("l:" + l);
47 // second visit
48 Iterator itr = l.iterator();
49 if (itr.hasNext()) { itr.next(); /* discard first */ }
50 traverse((GroovySourceAST)t,null,itr);
51 return t;
52 }
53
54 /**
55 * traverse an AST node
56 * @param t the AST node to traverse
57 * @param l A list to add line/col info to
58 * @param itr An iterator over a list of line/col
59 * @return A decorated AST node
60 */
61 private void traverse(GroovySourceAST t,List l,Iterator itr) {
62 while (t != null) {
63 // first visit of node
64 if (l != null) {
65 l.add(new LineColumn(t.getLine(),t.getColumn()));
66 }
67
68 // second visit of node
69 if (itr != null && itr.hasNext()) {
70 LineColumn lc = (LineColumn)itr.next();
71 if (t.getLineLast() == 0) {
72 int nextLine = lc.getLine();
73 int nextColumn = lc.getColumn();
74 if (nextLine < t.getLine() || (nextLine == t.getLine() && nextColumn < t.getColumn())) {
75 nextLine = t.getLine();
76 nextColumn = t.getColumn();
77 }
78 t.setLineLast(nextLine);
79 t.setColumnLast(nextColumn);
80 // This is a good point to call t.setSnippet(),
81 // but it bulks up the AST too much for production code.
82 }
83 }
84
85 GroovySourceAST child = (GroovySourceAST)t.getFirstChild();
86 if (child != null) {
87 traverse(child,l,itr);
88 }
89
90 t = (GroovySourceAST)t.getNextSibling();
91 }
92 }
93 }