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1
29 package jegg.impl;
30
31 import java.util.HashMap  ;
32 import java.util.Iterator ;
33 import java.util.Map ;
34
35 import jegg.Egg;
36 import jegg.Port;
37 import jegg.UnableToInitializeException;
38
39
40 import org.apache.commons.logging.Log;
41 import org.apache.commons.logging.LogFactory;
42
43
48 final public class HenHouse
49 {
50 private static final Log LOG = LogFactory.getLog(HenHouse.class);
51
52 private final Map _info = new HashMap ();
53 private final Map _eggs = new HashMap ();
54
55 public static HenHouse getHenHouse() { return HenHouseHolder.getHenHouse(); }
56
57 HenHouse() {}
58
59 void add(final EggInfo info)
60 {
61 _info.put(info.getEggName(), info);
62 _eggs.put(info.getEggName(), new PortImpl(info));
63 }
64
65 EggInfo hatch (final String eggName, final String handlerClass, final String dispatcherName, final boolean startEgg, boolean startDispatcher) throws HatchException
66 {
67 EggInfo info = new EggInfo(eggName, handlerClass, dispatcherName, startEgg);
68 add(info);
69 hatch(info, startEgg, startDispatcher);
70 return info;
71
72 }
73
74 void hatch(final EggInfo info, final boolean startEgg, final boolean startDispatcher) throws HatchException
75 {
76 if (LOG.isDebugEnabled())
77 LOG.debug("hatch("+info+", "+startEgg+")");
78
79 synchronized (info)
80 {
81 if (null == info.getEgg())
82 {
83 String eggName = info.getEggName();
84
85 try
86 {
87 Class claz = Class.forName(info.getHandlerClassName());
88 if (!Egg.class.isAssignableFrom(claz))
89 throw new HatchException(claz.getName()+" does not implement "+Egg.class.getName());
90 Egg h = (Egg) claz.newInstance();
91 EggShell egg = new EggShell(eggName,h);
92 egg.setProperties(info.getProperties());
93 PortImpl eggPort = (PortImpl) _eggs.get(eggName);
94 egg.setPort(eggPort);
95 eggPort.setOwner(egg);
96 info.setEgg(egg);
97 }
98 catch (ClassNotFoundException e)
99 {
100 throw new HatchException("Not found: " + info.getHandlerClassName(), e);
101 }
102 catch (InstantiationException e)
103 {
104 throw new HatchException("No default constructor: "+info.getHandlerClassName(), e);
105 }
106 catch (IllegalAccessException e)
107 {
108 throw new HatchException("IllegalAccessException: "+e.getMessage(), e);
109 }
110 }
111
112 if (startEgg)
113 {
114 if (!info.isResolved())
115 resolveDependencies(info, startDispatcher);
116
117 EggShell e = info.getEgg();
118 Egg h = e.getHandler();
119
120 try
121 {
122 h.init();
123 }
124 catch (UnableToInitializeException e1)
125 {
126 throw new HatchException("Can't initialize egg: "+e.getId(), e1);
127 }
128
129 Dispatcher d = (null == info.getDispatcherName())
130 ? Dispatcher.getDefaultScheduler()
131 : Dispatcher.getDispatcher(info.getDispatcherName(), startDispatcher);
132
133 e.assignTo(d);
134 }
135 }
136 }
137
138 Iterator iterator()
139 {
140 return _info.values().iterator();
141 }
142
143 void resolveDependencies(final EggInfo info, final boolean startDispatcher) throws HatchException
144 {
145 if (LOG.isDebugEnabled())
146 LOG.debug("resolve("+info.getEggName()+")");
147
148 synchronized (info)
149 {
150 if (info.isResolved())
151 return;
152
153 info.setResolved(true);
154 EggShell e = info.getEgg();
155 String [] deps = info.getDependencies();
156
157 for (int i=0; i<deps.length; ++i)
158 {
159 String depName = deps[i];
160 Port depPort = (Port) _eggs.get(depName);
161 e.dispatch(new MessageImpl(depPort,null,Priority.HIGH));
162 EggInfo depInfo = (EggInfo) _info.get(depName);
163 hatch(depInfo,true,startDispatcher);
164 }
165 }
166 }
167 }
168 |
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