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9  * by Oracle in the LICENSE file that accompanied this code.
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12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
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19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package sun.awt.X11;
27 
28 import sun.util.logging.PlatformLogger;
29 
30 import java.util.*;
31 
32 class XProtocol {
33     private static final PlatformLogger log = PlatformLogger.getLogger("sun.awt.X11.XProtocol");
34 
35     private Map<XAtom, XAtomList> atomToList = new HashMap<XAtom, XAtomList>();
36     private Map<XAtom, Long> atomToAnchor = new HashMap<XAtom, Long>();
37 
38     volatile boolean firstCheck = true;
39     /*
40      * Check that that the list of protocols specified by WM in property
41      * named LIST_NAME on the root window contains protocol PROTO.
42      */
checkProtocol(XAtom listName, XAtom protocol)43     boolean checkProtocol(XAtom listName, XAtom protocol) {
44         XAtomList protocols = atomToList.get(listName);
45 
46         if (protocols != null) {
47             return protocols.contains(protocol);
48         }
49 
50         protocols = listName.getAtomListPropertyList(XToolkit.getDefaultRootWindow());
51         atomToList.put(listName, protocols);
52         try {
53             return protocols.contains(protocol);
54         } finally {
55             if (firstCheck) {
56                 firstCheck = false;
57                 if (log.isLoggable(PlatformLogger.Level.FINE)) {
58                     log.fine("{0}:{1} supports {2}", this, listName, protocols);
59                 }
60             }
61         }
62     }
63 
64     /*
65      * Check for anchor_prop(anchor_type) on root, take the value as the
66      * window id and check if that window exists and has anchor_prop(anchor_type)
67      * with the same value (i.e. pointing back to self).
68      *
69      * Returns the anchor window, as some WM may put interesting stuff in
70      * its properties (e.g. sawfish).
71      */
checkAnchorImpl(XAtom anchorProp, long anchorType)72     long checkAnchorImpl(XAtom anchorProp, long anchorType) {
73         long root_xref, self_xref;
74 
75         XToolkit.awtLock();
76         try {
77             root_xref = anchorProp.get32Property(XToolkit.getDefaultRootWindow(),
78                                                  anchorType);
79         } finally {
80             XToolkit.awtUnlock();
81         }
82         if (root_xref == 0) {
83             return 0;
84         }
85         self_xref = anchorProp.get32Property(root_xref, anchorType);
86         if (self_xref != root_xref) {
87             return 0;
88         }
89         return self_xref;
90     }
checkAnchor(XAtom anchorProp, long anchorType)91     public long checkAnchor(XAtom anchorProp, long anchorType) {
92         Long val = atomToAnchor.get(anchorProp);
93         if (val != null) {
94             return val.longValue();
95         }
96         long res = checkAnchorImpl(anchorProp, anchorType);
97         atomToAnchor.put(anchorProp, res);
98         return res;
99     }
checkAnchor(XAtom anchorProp, XAtom anchorType)100     public long checkAnchor(XAtom anchorProp, XAtom anchorType) {
101         return checkAnchor(anchorProp, anchorType.getAtom());
102     }
103 
104 }
105