1   package gate.swing;
2   
3   import java.awt.*;
4   import java.beans.PropertyChangeEvent;
5   import java.beans.PropertyChangeListener;
6   
7   import javax.swing.Icon;
8   
9   /**
10   * VTextIcon is an Icon implementation which draws a short string vertically.
11   * It's useful for JTabbedPanes with LEFT or RIGHT tabs but can be used in any
12   * component which supports Icons, such as JLabel or JButton
13   * You can provide a hint to indicate whether to rotate the string
14   * to the left or right, or not at all, and it checks to make sure
15   * that the rotation is legal for the given string
16   * (for example, Chinese/Japanese/Korean scripts have special rules when
17   * drawn vertically and should never be rotated)
18   * <hr>
19   * NOTE: This class was taken from <br>
20   * <a href="http://www.macdevcenter.com/pub/a/mac/2002/03/22/vertical_text.html">
21   * this location</a>.
22   * <br>
23   * The author specifies:<br>
24   * &quot;Anybody can use the code for any purpose; I don't want any
25   * compensation, nor do I accept any liability.&quot;
26   *<hr>
27   * @author Lee Ann Rucker &lt;LRucker@mac.com&gt;
28   *
29   */
30  public class VerticalTextIcon implements Icon, PropertyChangeListener {
31    String fLabel;
32    String[] fCharStrings; // for efficiency, break the fLabel into one-char strings to be passed to drawString
33    int[] fCharWidths; // Roman characters should be centered when not rotated (Japanese fonts are monospaced)
34    int[] fPosition; // Japanese half-height characters need to be shifted when drawn vertically
35    int fWidth, fHeight, fCharHeight, fDescent; // Cached for speed
36    int fRotation;
37    Component fComponent;
38  
39    static final int POSITION_NORMAL = 0;
40    static final int POSITION_TOP_RIGHT = 1;
41    static final int POSITION_FAR_TOP_RIGHT = 2;
42  
43    public static final int ROTATE_DEFAULT = 0x00;
44    public static final int ROTATE_NONE = 0x01;
45    public static final int ROTATE_LEFT = 0x02;
46    public static final int ROTATE_RIGHT = 0x04;
47  
48    /**
49     * Creates a <code>VTextIcon</code> for the specified <code>component</code>
50     * with the specified <code>label</code>.
51     * It sets the orientation to the default for the string
52     * @see #verifyRotation
53     */
54    public VerticalTextIcon(Component component, String label) {
55      this(component, label, ROTATE_DEFAULT);
56    }
57  
58    /**
59     * Creates a <code>VTextIcon</code> for the specified <code>component</code>
60     * with the specified <code>label</code>.
61     * It sets the orientation to the provided value if it's legal for the string
62     * @see #verifyRotation
63     */
64    public VerticalTextIcon(Component component, String label, int rotateHint) {
65      fComponent = component;
66      fLabel = label;
67      fRotation = verifyRotation(label, rotateHint);
68      calcDimensions();
69      fComponent.addPropertyChangeListener(this);
70    }
71  
72    /**
73     * sets the label to the given string, updating the orientation as needed
74     * and invalidating the layout if the size changes
75     * @see #verifyRotation
76     */
77    public void setLabel(String label) {
78      fLabel = label;
79      fRotation = verifyRotation(label, fRotation); // Make sure the current rotation is still legal
80      recalcDimensions();
81    }
82  
83    /**
84     * Checks for changes to the font on the fComponent
85     * so that it can invalidate the layout if the size changes
86     */
87      public void propertyChange(PropertyChangeEvent e) {
88      String prop = e.getPropertyName();
89      if("font".equals(prop)) {
90        recalcDimensions();
91      }
92    }
93  
94    /**
95     * Calculates the dimensions.  If they've changed,
96     * invalidates the component
97     */
98    void recalcDimensions() {
99      int wOld = getIconWidth();
100     int hOld = getIconHeight();
101     calcDimensions();
102     if (wOld != getIconWidth() || hOld != getIconHeight())
103       fComponent.invalidate();
104   }
105 
106     void calcDimensions() {
107     FontMetrics fm = fComponent.getFontMetrics(fComponent.getFont());
108     fCharHeight = fm.getAscent() + fm.getDescent();
109     fDescent = fm.getDescent();
110     if (fRotation == ROTATE_NONE) {
111       int len = fLabel.length();
112       char data[] = new char[len];
113       fLabel.getChars(0, len, data, 0);
114       // if not rotated, width is that of the widest char in the string
115       fWidth = 0;
116       // we need an array of one-char strings for drawString
117       fCharStrings = new String[len];
118       fCharWidths = new int[len];
119       fPosition = new int[len];
120       char ch;
121       for (int i = 0; i < len; i++) {
122         ch = data[i];
123         fCharWidths[i] = fm.charWidth(ch);
124         if (fCharWidths[i] > fWidth)
125           fWidth = fCharWidths[i];
126         fCharStrings[i] = new String(data, i, 1);
127         // small kana and punctuation
128         if (sDrawsInTopRight.indexOf(ch) >= 0) // if ch is in sDrawsInTopRight
129           fPosition[i] = POSITION_TOP_RIGHT;
130         else if (sDrawsInFarTopRight.indexOf(ch) >= 0)
131           fPosition[i] = POSITION_FAR_TOP_RIGHT;
132         else
133           fPosition[i] = POSITION_NORMAL;
134       }
135       // and height is the font height * the char count, + one extra leading at the bottom
136       fHeight = fCharHeight * len + fDescent;
137     }
138     else {
139       // if rotated, width is the height of the string
140       fWidth = fCharHeight;
141       // and height is the width, plus some buffer space
142       fHeight = fm.stringWidth(fLabel) + 2*kBufferSpace;
143     }
144   }
145 
146    /**
147      * Draw the icon at the specified location.  Icon implementations
148      * may use the Component argument to get properties useful for
149      * painting, e.g. the foreground or background color.
150      */
151     public void paintIcon(Component c, Graphics g, int x, int y) {
152     // We don't insist that it be on the same Component
153     g.setColor(c.getForeground());
154     g.setFont(c.getFont());
155     if (fRotation == ROTATE_NONE) {
156       int yPos = y + fCharHeight;
157       for (int i = 0; i < fCharStrings.length; i++) {
158         // Special rules for Japanese - "half-height" characters (like ya, yu, yo in combinations)
159         // should draw in the top-right quadrant when drawn vertically
160         // - they draw in the bottom-left normally
161         int tweak;
162         switch (fPosition[i]) {
163           case POSITION_NORMAL:
164             // Roman fonts should be centered. Japanese fonts are always monospaced.
165             g.drawString(fCharStrings[i], x+((fWidth-fCharWidths[i])/2), yPos);
166             break;
167           case POSITION_TOP_RIGHT:
168             tweak = fCharHeight/3; // Should be 2, but they aren't actually half-height
169             g.drawString(fCharStrings[i], x+(tweak/2), yPos-tweak);
170             break;
171           case POSITION_FAR_TOP_RIGHT:
172             tweak = fCharHeight - fCharHeight/3;
173             g.drawString(fCharStrings[i], x+(tweak/2), yPos-tweak);
174             break;
175         }
176         yPos += fCharHeight;
177       }
178     }
179     else if (fRotation == ROTATE_LEFT) {
180       g.translate(x+fWidth,y+fHeight);
181       ((Graphics2D)g).rotate(-NINETY_DEGREES);
182       g.drawString(fLabel, kBufferSpace, -fDescent);
183       ((Graphics2D)g).rotate(NINETY_DEGREES);
184       g.translate(-(x+fWidth),-(y+fHeight));
185     }
186     else if (fRotation == ROTATE_RIGHT) {
187       g.translate(x,y);
188       ((Graphics2D)g).rotate(NINETY_DEGREES);
189       g.drawString(fLabel, kBufferSpace, -fDescent);
190       ((Graphics2D)g).rotate(-NINETY_DEGREES);
191       g.translate(-x,-y);
192     }
193 
194   }
195 
196     /**
197      * Returns the icon's width.
198      *
199      * @return an int specifying the fixed width of the icon.
200      */
201     public int getIconWidth() {
202     return fWidth;
203   }
204 
205     /**
206      * Returns the icon's height.
207      *
208      * @return an int specifying the fixed height of the icon.
209      */
210     public int getIconHeight() {
211     return fHeight;
212   }
213 
214   /**
215      verifyRotation
216 
217     returns the best rotation for the string (ROTATE_NONE, ROTATE_LEFT, ROTATE_RIGHT)
218 
219     This is public static so you can use it to test a string without creating a VTextIcon
220 
221    from http://www.unicode.org/unicode/reports/tr9/tr9-3.html
222    When setting text using the Arabic script in vertical lines,
223    it is more common to employ a horizontal baseline that
224    is rotated by 90� counterclockwise so that the characters
225    are ordered from top to bottom. Latin text and numbers
226    may be rotated 90� clockwise so that the characters
227    are also ordered from top to bottom.
228 
229     Rotation rules
230     - Roman can rotate left, right, or none - default right (counterclockwise)
231     - CJK can't rotate
232     - Arabic must rotate - default left (clockwise)
233 
234    from the online edition of _The Unicode Standard, Version 3.0_, file ch10.pdf page 4
235    Ideographs are found in three blocks of the Unicode Standard...
236    U+4E00-U+9FFF, U+3400-U+4DFF, U+F900-U+FAFF
237 
238    Hiragana is U+3040-U+309F, katakana is U+30A0-U+30FF
239 
240    from http://www.unicode.org/unicode/faq/writingdirections.html
241    East Asian scripts are frequently written in vertical lines
242    which run from top-to-bottom and are arrange columns either
243    from left-to-right (Mongolian) or right-to-left (other scripts).
244    Most characters use the same shape and orientation when displayed
245    horizontally or vertically, but many punctuation characters
246    will change their shape when displayed vertically.
247 
248    Letters and words from other scripts are generally rotated through
249    ninety degree angles so that they, too, will read from top to bottom.
250    That is, letters from left-to-right scripts will be rotated clockwise
251    and letters from right-to-left scripts counterclockwise, both
252    through ninety degree angles.
253 
254   Unlike the bidirectional case, the choice of vertical layout
255   is usually treated as a formatting style; therefore,
256   the Unicode Standard does not define default rendering behavior
257   for vertical text nor provide directionality controls designed to override such behavior
258 
259    */
260   public static int verifyRotation(String label, int rotateHint) {
261     boolean hasCJK = false;
262     boolean hasMustRotate = false; // Arabic, etc
263 
264     int len = label.length();
265     char data[] = new char[len];
266     char ch;
267     label.getChars(0, len, data, 0);
268     for (int i = 0; i < len; i++) {
269       ch = data[i];
270       if ((ch >= '\u4E00' && ch <= '\u9FFF') ||
271         (ch >= '\u3400' && ch <= '\u4DFF') ||
272         (ch >= '\uF900' && ch <= '\uFAFF') ||
273         (ch >= '\u3040' && ch <= '\u309F') ||
274         (ch >= '\u30A0' && ch <= '\u30FF') )
275          hasCJK = true;
276       if ((ch >= '\u0590' && ch <= '\u05FF') || // Hebrew
277         (ch >= '\u0600' && ch <= '\u06FF') || // Arabic
278         (ch >= '\u0700' && ch <= '\u074F') ) // Syriac
279          hasMustRotate = true;
280     }
281     // If you mix Arabic with Chinese, you're on your own
282     if (hasCJK)
283       return DEFAULT_CJK;
284 
285     int legal = hasMustRotate ? LEGAL_MUST_ROTATE : LEGAL_ROMAN;
286     if ((rotateHint & legal) > 0)
287       return rotateHint;
288 
289     // The hint wasn't legal, or it was zero
290     return hasMustRotate ? DEFAULT_MUST_ROTATE : DEFAULT_ROMAN;
291   }
292 
293   // The small kana characters and Japanese punctuation that draw in the top right quadrant:
294   // small a, i, u, e, o, tsu, ya, yu, yo, wa  (katakana only) ka ke
295   static final String sDrawsInTopRight =
296     "\u3041\u3043\u3045\u3047\u3049\u3063\u3083\u3085\u3087\u308E" + // hiragana
297     "\u30A1\u30A3\u30A5\u30A7\u30A9\u30C3\u30E3\u30E5\u30E7\u30EE\u30F5\u30F6"; // katakana
298   static final String sDrawsInFarTopRight = "\u3001\u3002"; // comma, full stop
299 
300   static final int DEFAULT_CJK = ROTATE_NONE;
301   static final int LEGAL_ROMAN = ROTATE_NONE | ROTATE_LEFT | ROTATE_RIGHT;
302   static final int DEFAULT_ROMAN = ROTATE_RIGHT;
303   static final int LEGAL_MUST_ROTATE = ROTATE_LEFT | ROTATE_RIGHT;
304   static final int DEFAULT_MUST_ROTATE = ROTATE_LEFT;
305 
306   static final double NINETY_DEGREES = Math.toRadians(90.0);
307   static final int kBufferSpace = 5;
308 }