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1
15 package org.apache.hivemind.lib.impl;
16
17 import java.lang.reflect.Constructor  ;
18 import java.lang.reflect.Modifier ;
19 import java.rmi.RemoteException ;
20
21 import org.apache.hivemind.ApplicationRuntimeException;
22 import org.apache.hivemind.ServiceImplementationFactory;
23 import org.apache.hivemind.ServiceImplementationFactoryParameters;
24 import org.apache.hivemind.impl.BaseLocatable;
25 import org.apache.hivemind.internal.Module;
26 import org.apache.hivemind.lib.NameLookup;
27 import org.apache.hivemind.lib.RemoteExceptionCoordinator;
28 import org.apache.hivemind.service.BodyBuilder;
29 import org.apache.hivemind.service.ClassFab;
30 import org.apache.hivemind.service.ClassFabUtils;
31 import org.apache.hivemind.service.ClassFactory;
32 import org.apache.hivemind.service.MethodIterator;
33 import org.apache.hivemind.service.MethodSignature;
34
35
46 public class EJBProxyFactory extends BaseLocatable implements ServiceImplementationFactory
47 {
48 private NameLookup _nameLookup;
49 private RemoteExceptionCoordinator _coordinator;
50 private ClassFactory _classFactory;
51
52 public Object createCoreServiceImplementation(ServiceImplementationFactoryParameters factoryParameters)
53 {
54 EJBProxyParameters proxyParameters = (EJBProxyParameters) factoryParameters.getFirstParameter();
55 String jndiName = proxyParameters.getJndiName();
56 String homeInterfaceClassName = proxyParameters.getHomeInterfaceClassName();
57
58
60 Module module = factoryParameters.getInvokingModule();
61 Class serviceInterface = factoryParameters.getServiceInterface();
62
63 Class homeInterface = module.resolveType(homeInterfaceClassName);
64
65 String proxyClassName = ClassFabUtils.generateClassName(serviceInterface);
66
67 ClassFab classFab =
68 _classFactory.newClass(
69 proxyClassName,
70 AbstractEJBProxy.class);
71
72 classFab.addInterface(serviceInterface);
73
74 classFab.addField("_remote", serviceInterface);
75
76 addClearCachedMethod(classFab);
77
78 addLookupMethod(classFab, homeInterface, serviceInterface, jndiName);
79
80 addServiceMethods(classFab, serviceInterface, factoryParameters.getServiceId(), jndiName);
81
82 addConstructor(classFab);
83
84 Class proxyClass = classFab.createClass();
85
86 return invokeConstructor(proxyClass, proxyParameters.getNameLookup(_nameLookup));
87 }
88
89 private void addClearCachedMethod(ClassFab classFab)
90 {
91 classFab.addMethod(
92 Modifier.PROTECTED,
93 new MethodSignature(void.class, "_clearCachedReferences", null, null),
94 "_remote = null;");
95 }
96
97 private void addLookupMethod(
98 ClassFab classFab,
99 Class homeInterface,
100 Class remoteInterface,
101 String jndiName)
102 {
103 String homeInterfaceName = homeInterface.getName();
104
105 BodyBuilder builder = new BodyBuilder();
106
107 builder.begin();
108
109 builder.addln("if (_remote != null)");
110 builder.addln(" return _remote;");
111
112 builder.add(homeInterfaceName);
113 builder.add(" home = (");
114 builder.add(homeInterfaceName);
115 builder.add(") _lookup(");
116 builder.addQuoted(jndiName);
117 builder.addln(");");
118
119 builder.add("try");
120 builder.begin();
121 builder.add("_remote = home.create();");
122 builder.end();
123 builder.add("catch (javax.ejb.CreateException ex)");
124 builder.begin();
125 builder.add("throw new java.rmi.RemoteException(ex.getMessage(), ex);");
126 builder.end();
127
128 builder.add("return _remote;");
129
130 builder.end();
131
132 classFab.addMethod(
133 Modifier.SYNCHRONIZED + Modifier.PRIVATE,
134 new MethodSignature(
135 remoteInterface,
136 "_lookupRemote",
137 null,
138 new Class [] { RemoteException .class }),
139 builder.toString());
140
141 }
142
143 private void addServiceMethods(
144 ClassFab classFab,
145 Class serviceInterface,
146 String serviceId,
147 String jndiName)
148 {
149 MethodIterator mi = new MethodIterator(serviceInterface);
150
151 while (mi.hasNext())
152 {
153 addServiceMethod(classFab, mi.next());
154 }
155
156 if (!mi.getToString())
157 addToStringMethod(classFab, serviceInterface, serviceId, jndiName);
158 }
159
160 private void addServiceMethod(ClassFab classFab, MethodSignature sig)
161 {
162 String methodName = sig.getName();
163
164 boolean isVoid = sig.getReturnType().equals(Void.TYPE);
165
166 BodyBuilder builder = new BodyBuilder();
167
168 builder.begin();
169
170 builder.addln("boolean first = true;");
171 builder.add("while (true)");
172 builder.begin();
173
174 builder.add("try");
175 builder.begin();
176
177 if (!isVoid)
178 builder.add("return ");
179
180 builder.add("_lookupRemote().");
181 builder.add(methodName);
182 builder.addln("($$);");
183
184 if (isVoid)
185 builder.addln("return;");
186
187 builder.end();
189 builder.add("catch (java.rmi.RemoteException ex)");
190 builder.begin();
191
192 builder.addln("if (first)");
193 builder.begin();
194
195 builder.addln("_handleRemoteException(ex);");
196 builder.addln("first = false;");
197
198 builder.end(); builder.addln("else");
200 builder.add(" throw ex;");
201 builder.end(); builder.end(); builder.end();
204
205 classFab.addMethod(Modifier.PUBLIC, sig, builder.toString());
206 }
207
208 private void addToStringMethod(
209 ClassFab classFab,
210 Class serviceInterface,
211 String serviceId,
212 String jndiName)
213 {
214 ClassFabUtils.addToStringMethod(
215 classFab,
216 ImplMessages.ejbProxyDescription(serviceId, serviceInterface, jndiName));
217 }
218
219 private void addConstructor(ClassFab classFab)
220 {
221 classFab.addConstructor(
222 new Class [] { NameLookup.class, RemoteExceptionCoordinator.class },
223 null,
224 "super($1, $2);");
225 }
226
227 private Object invokeConstructor(Class proxyClass, NameLookup nameLookup)
228 {
229 try
230 {
231 Constructor c =
232 proxyClass.getConstructor(
233 new Class [] { NameLookup.class, RemoteExceptionCoordinator.class });
234
235 return c.newInstance(new Object [] { nameLookup, _coordinator });
236 }
237 catch (Exception ex)
238 {
239 throw new ApplicationRuntimeException(ex);
240 }
241 }
242
243 public void setClassFactory(ClassFactory factory)
244 {
245 _classFactory = factory;
246 }
247
248 public void setCoordinator(RemoteExceptionCoordinator coordinator)
249 {
250 _coordinator = coordinator;
251 }
252
253 public void setNameLookup(NameLookup lookup)
254 {
255 _nameLookup = lookup;
256 }
257
258 }
259 |
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