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25 package javax.swing.text;
26 
27 
28 /**
29  * Interface for <code>View</code>s that have size dependent upon tabs.
30  *
31  * @author  Timothy Prinzing
32  * @author  Scott Violet
33  * @see TabExpander
34  * @see LabelView
35  * @see ParagraphView
36  */
37 public interface TabableView {
38 
39     /**
40      * Determines the desired span when using the given
41      * tab expansion implementation.  If a container
42      * calls this method, it will do so prior to the
43      * normal layout which would call getPreferredSpan.
44      * A view implementing this should give the same
45      * result in any subsequent calls to getPreferredSpan
46      * along the axis of tab expansion.
47      *
48      * @param x the position the view would be located
49      *  at for the purpose of tab expansion &gt;= 0.
50      * @param e how to expand the tabs when encountered.
51      * @return the desired span &gt;= 0
52      */
getTabbedSpan(float x, TabExpander e)53     float getTabbedSpan(float x, TabExpander e);
54 
55     /**
56      * Determines the span along the same axis as tab
57      * expansion for a portion of the view.  This is
58      * intended for use by the TabExpander for cases
59      * where the tab expansion involves aligning the
60      * portion of text that doesn't have whitespace
61      * relative to the tab stop.  There is therefore
62      * an assumption that the range given does not
63      * contain tabs.
64      *
65      * @param p0 the starting location in the text document &gt;= 0
66      * @param p1 the ending location in the text document &gt;= p0
67      * @return the span &gt;= 0
68      */
getPartialSpan(int p0, int p1)69     float getPartialSpan(int p0, int p1);
70 }
71