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1
15 package org.apache.hivemind.service.impl;
16
17 import java.lang.reflect.Modifier  ;
18 import java.util.Iterator ;
19 import java.util.List ;
20
21 import org.apache.commons.logging.Log;
22 import org.apache.hivemind.InterceptorStack;
23 import org.apache.hivemind.methodmatch.MethodMatcher;
24 import org.apache.hivemind.service.BodyBuilder;
25 import org.apache.hivemind.service.ClassFab;
26 import org.apache.hivemind.service.ClassFabUtils;
27 import org.apache.hivemind.service.ClassFactory;
28 import org.apache.hivemind.service.MethodContribution;
29 import org.apache.hivemind.service.MethodFab;
30 import org.apache.hivemind.service.MethodIterator;
31 import org.apache.hivemind.service.MethodSignature;
32
33
47 public class LoggingInterceptorClassFactory
48 {
49 private ClassFactory _factory;
50
51 public LoggingInterceptorClassFactory(ClassFactory factory)
52 {
53 _factory = factory;
54 }
55
56
60 private void addPassThruMethodImplementation(ClassFab classFab, MethodSignature sig)
61 {
62 BodyBuilder builder = new BodyBuilder();
63 builder.begin();
64
65 builder.add("return ($r) _delegate.");
66 builder.add(sig.getName());
67 builder.addln("($$);");
68
69 builder.end();
70
71 classFab.addMethod(Modifier.PUBLIC, sig, builder.toString());
72 }
73
74 protected void addServiceMethodImplementation(ClassFab classFab, MethodSignature sig)
75 {
76 Class returnType = sig.getReturnType();
77 String methodName = sig.getName();
78
79 boolean isVoid = (returnType == void.class);
80
81 BodyBuilder builder = new BodyBuilder();
82
83 builder.begin();
84 builder.addln("boolean debug = _log.isDebugEnabled();");
85
86 builder.addln("if (debug)");
87 builder.add(" org.apache.hivemind.service.impl.LoggingUtils.entry(_log, ");
88 builder.addQuoted(methodName);
89 builder.addln(", $args);");
90
91 if (!isVoid)
92 {
93 builder.add(ClassFabUtils.getJavaClassName(returnType));
94 builder.add(" result = ");
95 }
96
97 builder.add("_delegate.");
98 builder.add(methodName);
99 builder.addln("($$);");
100
101 if (isVoid)
102 {
103 builder.addln("if (debug)");
104 builder.add(" org.apache.hivemind.service.impl.LoggingUtils.voidExit(_log, ");
105 builder.addQuoted(methodName);
106 builder.addln(");");
107 }
108 else
109 {
110 builder.addln("if (debug)");
111 builder.add(" org.apache.hivemind.service.impl.LoggingUtils.exit(_log, ");
112 builder.addQuoted(methodName);
113 builder.addln(", ($w)result);");
114 builder.addln("return result;");
115 }
116
117 builder.end();
118
119 MethodFab methodFab = classFab.addMethod(Modifier.PUBLIC, sig, builder.toString());
120
121 builder.clear();
122
123 builder.begin();
124 builder.add("org.apache.hivemind.service.impl.LoggingUtils.exception(_log, ");
125 builder.addQuoted(methodName);
126 builder.addln(", $e);");
127 builder.addln("throw $e;");
128 builder.end();
129
130 String body = builder.toString();
131
132 Class [] exceptions = sig.getExceptionTypes();
133
134 int count = exceptions.length;
135
136 for (int i = 0; i < count; i++)
137 {
138 methodFab.addCatch(exceptions[i], body);
139 }
140
141
144 methodFab.addCatch(RuntimeException .class, body);
145 }
146
147 protected void addServiceMethods(InterceptorStack stack, ClassFab fab, List parameters)
148 {
149 MethodMatcher matcher = buildMethodMatcher(parameters);
150
151 MethodIterator mi = new MethodIterator(stack.getServiceInterface());
152
153 while (mi.hasNext())
154 {
155 MethodSignature sig = mi.next();
156
157 if (includeMethod(matcher, sig))
158 addServiceMethodImplementation(fab, sig);
159 else
160 addPassThruMethodImplementation(fab, sig);
161 }
162
163 if (!mi.getToString())
164 addToStringMethod(stack, fab);
165 }
166
167
171 protected void addToStringMethod(InterceptorStack stack, ClassFab fab)
172 {
173 ClassFabUtils.addToStringMethod(
174 fab,
175 "<LoggingInterceptor for "
176 + stack.getServiceExtensionPointId()
177 + "("
178 + stack.getServiceInterface().getName()
179 + ")>");
180
181 }
182
183 private MethodMatcher buildMethodMatcher(List parameters)
184 {
185 MethodMatcher result = null;
186
187 Iterator i = parameters.iterator();
188 while (i.hasNext())
189 {
190 MethodContribution mc = (MethodContribution) i.next();
191
192 if (result == null)
193 result = new MethodMatcher();
194
195 result.put(mc.getMethodPattern(), mc);
196 }
197
198 return result;
199 }
200
201
204 public Class constructInterceptorClass(InterceptorStack stack, List parameters)
205 {
206 Class serviceInterfaceClass = stack.getServiceInterface();
207
208 String name = ClassFabUtils.generateClassName(serviceInterfaceClass);
209
210 ClassFab classFab = _factory.newClass(name, Object .class);
211
212 classFab.addInterface(serviceInterfaceClass);
213
214 createInfrastructure(stack, classFab);
215
216 addServiceMethods(stack, classFab, parameters);
217
218 return classFab.createClass();
219 }
220
221 private void createInfrastructure(InterceptorStack stack, ClassFab classFab)
222 {
223 Class topClass = ClassFabUtils.getInstanceClass(classFab, stack.peek(), stack.getServiceInterface());
224
225 classFab.addField("_log", Log.class);
226
227
233 classFab.addField("_delegate", topClass);
234
235 classFab.addConstructor(
236 new Class [] { Log.class, topClass },
237 null,
238 "{ _log = $1; _delegate = $2; }");
239 }
240
241 private boolean includeMethod(MethodMatcher matcher, MethodSignature sig)
242 {
243 if (matcher == null)
244 return true;
245
246 MethodContribution mc = (MethodContribution) matcher.get(sig);
247
248 return mc == null || mc.getInclude();
249 }
250
251 }
252 |
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