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1
9 package org.jboss.portal.server.kernel.state;
10
11 import org.apache.log4j.Logger;
12 import org.jboss.portal.server.kernel.TransitionNotPossibleException;
13
14
20 public class StateMachine
21 {
22
23 private final Logger log;
24 private State state;
25
26 public StateMachine(Logger log)
27 {
28 if (log == null)
29 {
30 throw new IllegalArgumentException  ("log must not be null");
31 }
32 this.log = log;
33 this.state = State.UNREGISTERED;
34 }
35
36 public State getState()
37 {
38 return state;
39 }
40
41 public void register(boolean test) throws TransitionNotPossibleException
42 {
43 if (state == State.UNREGISTERED)
44 {
45 if (!test)
46 {
47 updateState(State.REGISTERED);
48 log.debug("registered");
49 }
50 }
51 else
52 {
53 throw new TransitionNotPossibleException("Cannot call register() on " + state);
54 }
55 }
56
57 public void create(boolean test) throws TransitionNotPossibleException
58 {
59 if (state == State.REGISTERED)
60 {
61 if (!test)
62 {
63 updateState(State.STOPPED);
64 log.debug("created");
65 }
66 }
67 else
68 {
69 throw new TransitionNotPossibleException("Cannot call create() on " + state);
70 }
71 }
72
73 public void start(boolean test) throws TransitionNotPossibleException
74 {
75 if (state == State.STOPPED)
76 {
77 if (!test)
78 {
79 state = State.STARTED;
80 updateState(State.STARTED);
81 log.debug("started");
82 }
83 }
84 else
85 {
86 throw new TransitionNotPossibleException("Cannot call start() on " + state);
87 }
88 }
89
90 public void stop(boolean test) throws TransitionNotPossibleException
91 {
92 if (state == State.STARTED)
93 {
94 if (!test)
95 {
96 updateState(State.STOPPED);
97 log.debug("stopped");
98 }
99 }
100 else
101 {
102 throw new TransitionNotPossibleException("Cannot call stop() on " + state);
103 }
104 }
105
106 public void destroy(boolean test) throws TransitionNotPossibleException
107 {
108 if (state == State.STOPPED || state == State.FAILED)
109 {
110 if (!test)
111 {
112 updateState(State.REGISTERED);
113 log.debug("destroyed");
114 }
115 }
116 else
117 {
118 throw new TransitionNotPossibleException("Cannot call destroy() on " + state);
119 }
120 }
121
122 public void unregister(boolean test) throws TransitionNotPossibleException
123 {
124 if (state == State.REGISTERED || state == State.FAILED)
125 {
126 if (!test)
127 {
128 updateState(State.UNREGISTERED);
129 log.debug("unregistered");
130 }
131 }
132 else
133 {
134 throw new TransitionNotPossibleException("Cannot call removeIDependOn() on " + state);
135 }
136 }
137
138 public void fail(boolean test) throws TransitionNotPossibleException
139 {
140 if (!test)
141 {
142 updateState(State.FAILED);
143 log.debug("failed");
144
145 }
146 }
147
148 private void updateState(State newState)
149 {
150 State oldState = state;
151 state = newState;
152 if (oldState != newState)
153 {
154 stateChanged(oldState, newState);
155 }
156 }
157
158 protected void stateChanged(State oldState, State newState)
159 {
160 }
161 }
162 |
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