KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > edu > rice > cs > drjava > model > definitions > indent > QuestionNewParenPhrase


1 /*BEGIN_COPYRIGHT_BLOCK
2  *
3  * This file is part of DrJava. Download the current version of this project from http://www.drjava.org/
4  * or http://sourceforge.net/projects/drjava/
5  *
6  * DrJava Open Source License
7  *
8  * Copyright (C) 2001-2006 JavaPLT group at Rice University (javaplt@rice.edu). All rights reserved.
9  *
10  * Developed by: Java Programming Languages Team, Rice University, http://www.cs.rice.edu/~javaplt/
11  *
12  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
13  * documentation files (the "Software"), to deal with the Software without restriction, including without limitation
14  * the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
15  * to permit persons to whom the Software is furnished to do so, subject to the following conditions:
16  *
17  * - Redistributions of source code must retain the above copyright notice, this list of conditions and the
18  * following disclaimers.
19  * - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
20  * following disclaimers in the documentation and/or other materials provided with the distribution.
21  * - Neither the names of DrJava, the JavaPLT, Rice University, nor the names of its contributors may be used to
22  * endorse or promote products derived from this Software without specific prior written permission.
23  * - Products derived from this software may not be called "DrJava" nor use the term "DrJava" as part of their
24  * names without prior written permission from the JavaPLT group. For permission, write to javaplt@rice.edu.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
27  * THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
28  * CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
29  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
30  * WITH THE SOFTWARE.
31  *
32  *END_COPYRIGHT_BLOCK*/
33
34 package edu.rice.cs.drjava.model.definitions.indent;
35
36 import javax.swing.text.*;
37 import edu.rice.cs.util.UnexpectedException;
38 import edu.rice.cs.drjava.model.AbstractDJDocument;
39
40 /** Question rule in the indentation decision tree. Determines if the current line starts a new "phrase" within a
41   * parenthesized expression. Specifically, this rule determines if the previous line ends in a comma, semicolon,
42   * open paren, or open bracket. Note that whitespace, blank lines, and comments are disregarded.
43   *
44  * @version $Id: QuestionNewParenPhrase.java 3901 2006-06-30 05:28:11Z rcartwright $
45  */
46 public class QuestionNewParenPhrase extends IndentRuleQuestion {
47   
48   /**
49    * Constructs a new rule to determine if the current line starts
50    * new paren phrase.
51    * @param yesRule Rule to use if this rule holds
52    * @param noRule Rule to use if this rule does not hold
53    */
54   public QuestionNewParenPhrase(IndentRule yesRule, IndentRule noRule) {
55     super(yesRule, noRule);
56   }
57  
58   /**
59    * Determines if the previous line ends in a comma, semicolon,
60    * open paren, open bracket, operator, or comparator.
61    * @param doc AbstractDJDocument containing the line to be indented.
62    * @return true if this node's rule holds.
63    */
64   boolean applyRule(AbstractDJDocument doc, int reason) {
65
66     try {
67       // Find start of line
68 int here = doc.getCurrentLocation();
69       int startLine = doc.getLineStartPos(here);
70       
71       if (startLine > AbstractDJDocument.DOCSTART) {
72         // Find previous delimiter (looking in paren phrases)
73 char[] delims = {';', ',', '(', '[',
74           '&', '|', '+', '-', '*', '/', '%',
75           '=', '<', '>', '}'
76         };
77         int prevDelim = doc.findPrevDelimiter(startLine, delims, false);
78         if (prevDelim == AbstractDJDocument.ERROR_INDEX) {
79           return false;
80         }
81         
82         // Make sure the delim is the previous non-WS char
83 int nextNonWS = doc.getFirstNonWSCharPos(prevDelim + 1);
84         if (nextNonWS == AbstractDJDocument.ERROR_INDEX) {
85           nextNonWS = startLine;
86         }
87         return (nextNonWS >= startLine);
88       }
89     }
90     catch (BadLocationException e) {
91       // Shouldn't happen
92 throw new UnexpectedException(e);
93     }
94     // On first line
95 return false;
96   }
97 }
98
Popular Tags