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


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33
34 package edu.rice.cs.drjava.model.definitions.indent;
35
36 import edu.rice.cs.drjava.model.AbstractDJDocument;
37 import edu.rice.cs.drjava.model.definitions.reducedmodel.*;
38
39 /** Given the start of the current line is inside a block comment, asks
40   * whether the comment begins on the "previous line," ignoring white space.
41   *
42   * @version $Id: QuestionPrevLineStartsComment.java 3900 2006-06-29 13:16:38Z rcartwright $
43   */
44 class QuestionPrevLineStartsComment extends IndentRuleQuestion {
45   
46   QuestionPrevLineStartsComment(IndentRule yesRule, IndentRule noRule) {
47     super(yesRule, noRule);
48   }
49   
50   /** Determines if the previous line in the document starts a block comment.
51     * We know that the current line is in a block comment. Therefore, if the
52     * start of the previous line is not inside of a block comment, then the
53     * previous line must have started the comment.
54     * <p>
55     * There is an exception to this; however, it is handled adequately. Consider
56     * the case when the previous line contains the following code:
57     * <code>*&#47; bar(); &#47;*</code>
58     * <p>
59     * Our approach will say that since the beginning of the previous line is
60     * inside of a comment, the previous line did not start the comment. This
61     * is acceptable because we think of the previous line as a continuation
62     * of a larger commented out region.
63     * @param doc AbstractDJDocument containing the line to be indented.
64     * @return true if this node's rule holds.
65     */
66   boolean applyRule(AbstractDJDocument doc, int reason) {
67
68       int cursor;
69
70     // Move back to start of current line
71 cursor = doc.getLineStartPos(doc.getCurrentLocation());
72     
73     /* If the start of the current line is the start of the document, there was no previous line and so this line must
74      * have started the comment. */
75     if (cursor == AbstractDJDocument.DOCSTART) return false;
76     
77     // Move the cursor to the previous line
78 cursor = cursor - 1;
79     
80     // Move it to the start of the previous line
81 cursor = doc.getLineStartPos(cursor);
82     
83     // Return if the start of the previous line is in a comment.
84 // BraceReduction reduced = doc.getReduced();
85 doc.resetReducedModelLocation();
86     ReducedModelState state = doc.stateAtRelLocation(cursor - doc.getCurrentLocation());
87     return !state.equals(ReducedModelStates.INSIDE_BLOCK_COMMENT);
88   }
89 }
90
91
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