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1
15 package org.apache.hivemind.lib.impl;
16
17 import java.lang.reflect.Modifier  ;
18
19 import org.apache.hivemind.ApplicationRuntimeException;
20 import org.apache.hivemind.ServiceImplementationFactory;
21 import org.apache.hivemind.ServiceImplementationFactoryParameters;
22 import org.apache.hivemind.internal.ServicePoint;
23 import org.apache.hivemind.service.BodyBuilder;
24 import org.apache.hivemind.service.ClassFab;
25 import org.apache.hivemind.service.ClassFabUtils;
26 import org.apache.hivemind.service.ClassFactory;
27 import org.apache.hivemind.service.MethodIterator;
28 import org.apache.hivemind.service.MethodSignature;
29 import org.apache.hivemind.util.ConstructorUtils;
30 import org.apache.hivemind.util.PropertyAdaptor;
31 import org.apache.hivemind.util.PropertyUtils;
32
33
40 public class ServicePropertyFactory implements ServiceImplementationFactory
41 {
42 private ClassFactory _classFactory;
43
44 public Object createCoreServiceImplementation(
45 ServiceImplementationFactoryParameters factoryParameters)
46 {
47 ServicePropertyFactoryParameter p = (ServicePropertyFactoryParameter) factoryParameters
48 .getFirstParameter();
49
50 ServicePoint targetServicePoint = p.getServicePoint();
51 final Class targetServiceInterface = targetServicePoint.getServiceInterface();
52 final Object targetService = targetServicePoint.getService( targetServiceInterface );
53 String propertyName = p.getPropertyName();
54
55 PropertyAdaptor pa = PropertyUtils.getPropertyAdaptor(targetService, propertyName);
56
57 String readMethodName = pa.getReadMethodName();
58
59 if (readMethodName == null)
60 throw new ApplicationRuntimeException(ImplMessages.servicePropertyNotReadable(
61 propertyName,
62 targetService), null, p.getLocation(), null);
63 Class serviceInterface = factoryParameters.getServiceInterface();
64
65 if (!(serviceInterface.isAssignableFrom(pa.getPropertyType())))
66 throw new ApplicationRuntimeException(ImplMessages.servicePropertyWrongType(
67 propertyName,
68 targetService,
69 pa.getPropertyType(),
70 serviceInterface), p.getLocation(), null);
71
72
74 String name = ClassFabUtils.generateClassName(serviceInterface);
75
76 ClassFab cf = _classFactory.newClass(name, Object .class);
77
78 addInfrastructure(cf, targetService, serviceInterface, targetServiceInterface, propertyName, readMethodName);
79
80 addMethods(
81 cf,
82 factoryParameters.getServiceId(),
83 serviceInterface,
84 propertyName,
85 targetService);
86
87 Class proxyClass = cf.createClass();
88
89 try
90 {
91 return ConstructorUtils.invokeConstructor(proxyClass, new Object []
92 { targetService });
93 }
94 catch (Throwable ex)
95 {
96 throw new ApplicationRuntimeException(ex.getMessage(), p.getLocation(), ex);
97 }
98 }
99
100 private void addInfrastructure(ClassFab cf, Object targetService, Class serviceInterface, Class targetServiceInterface,
101 String propertyName, String readPropertyMethodName)
102 {
103 cf.addInterface(serviceInterface);
104
105 Class targetServiceClass = ClassFabUtils.getInstanceClass(cf, targetService, targetServiceInterface);
106
107 cf.addField("_targetService", targetServiceClass);
108
109 cf.addConstructor(new Class []
110 { targetServiceClass }, null, "{ super(); _targetService = $1; }");
111
112 BodyBuilder b = new BodyBuilder();
113
114 b.begin();
115 b.addln(
116 "{0} property = _targetService.{1}();",
117 serviceInterface.getName(),
118 readPropertyMethodName);
119
120 b.addln("if (property == null)");
121 b.add(" throw new java.lang.NullPointerException(");
122 b.addQuoted(ImplMessages.servicePropertyWasNull(propertyName, targetService));
123 b.addln(");");
124
125 b.addln("return property;");
126
127 b.end();
128
129 MethodSignature sig = new MethodSignature(serviceInterface, "_targetServiceProperty", null,
130 null);
131 cf.addMethod(Modifier.FINAL | Modifier.PRIVATE, sig, b.toString());
132 }
133
134 private void addMethods(ClassFab cf, String serviceId, Class serviceInterface,
135 String propertyName, Object targetService)
136 {
137 MethodIterator mi = new MethodIterator(serviceInterface);
138
139 while (mi.hasNext())
140 {
141 MethodSignature sig = mi.next();
142
143 String body = "return ($r) _targetServiceProperty()." + sig.getName() + "($$);";
144
145 cf.addMethod(Modifier.PUBLIC, sig, body);
146 }
147
148 if (!mi.getToString())
149 ClassFabUtils.addToStringMethod(cf, ImplMessages.servicePropertyToString(
150 serviceId,
151 serviceInterface,
152 propertyName,
153 targetService));
154 }
155
156 public void setClassFactory(ClassFactory factory)
157 {
158 _classFactory = factory;
159 }
160 } |
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