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1 package org.objectweb.celtix.application;
2
3 import java.util.ResourceBundle  ;
4 import java.util.logging.Logger ;
5
6 import org.objectweb.celtix.common.i18n.BundleUtils;
7 import org.objectweb.celtix.common.i18n.Message;
8 import org.objectweb.celtix.plugins.PluginException;
9
10
11 public class PluginStateMachine {
12
13 private static final Logger LOG = Logger.getLogger(PluginStateMachine.class.getName());
14 private static final ResourceBundle BUNDLE = BundleUtils.getBundle(PluginStateMachine.class);
15
16 public enum PluginState { UNLOADED, LOADING, LOADED };
17
18 private PluginState state;
19
20 PluginStateMachine() {
21 this(PluginState.UNLOADED);
22 }
23
24 PluginStateMachine(PluginState initialState) {
25 state = initialState;
26 }
27
28 PluginState getCurrentState() {
29 return state;
30 }
31
32 synchronized void setNextState(PluginState nextState) throws PluginException {
33 if ((state == PluginState.UNLOADED && nextState == PluginState.LOADING)
34 || (state == PluginState.LOADING && nextState == PluginState.LOADED)
35 || (state == PluginState.LOADED && nextState == PluginState.UNLOADED)) {
36 LOG.fine("changing state from " + state + " to " + nextState);
37 state = nextState;
38 } else {
39 Message msg = new Message("INVALID_STATE_TRANSITION_EXC", BUNDLE, state, nextState);
40 throw new PluginException(msg);
41 }
42 notifyAll();
43 }
44
45 synchronized void waitForState(PluginState awaitedState) {
46 while (state != awaitedState) {
47 LOG.fine("waiting for state so change from " + state + " to " + awaitedState);
48 try {
49 wait();
50 } catch (InterruptedException ex) {
51 }
53 }
54 }
55 }
56 |
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