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13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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24  */
25 
26 package java.lang;
27 
28 import jdk.internal.misc.Signal;
29 
30 
31 /**
32  * Package-private utility class for setting up and tearing down
33  * platform-specific support for termination-triggered shutdowns.
34  *
35  * @author   Mark Reinhold
36  * @since    1.3
37  */
38 
39 class Terminator {
40 
41     private static Signal.Handler handler = null;
42 
43     /* Invocations of setup and teardown are already synchronized
44      * on the shutdown lock, so no further synchronization is needed here
45      */
46 
setup()47     static void setup() {
48         if (handler != null) return;
49         Signal.Handler sh = new Signal.Handler() {
50             public void handle(Signal sig) {
51                 Shutdown.exit(sig.getNumber() + 0200);
52             }
53         };
54         handler = sh;
55 
56         // When -Xrs is specified the user is responsible for
57         // ensuring that shutdown hooks are run by calling
58         // System.exit()
59         try {
60             Signal.handle(new Signal("INT"), sh);
61         } catch (IllegalArgumentException e) {
62         }
63         try {
64             Signal.handle(new Signal("TERM"), sh);
65         } catch (IllegalArgumentException e) {
66         }
67     }
68 
teardown()69     static void teardown() {
70         /* The current sun.misc.Signal class does not support
71          * the cancellation of handlers
72          */
73     }
74 
75 }
76