public InjectionNode generateProxy(InjectionNode injectionNode) {
if (!aopProxiesGenerated.containsKey(injectionNode.getClassName())) {
InjectionNode proxyInjectionNode = innerGenerateProxyCode(injectionNode);
aopProxiesGenerated.put(injectionNode.getClassName(), proxyInjectionNode);
}
return aopProxiesGenerated.get(injectionNode.getClassName());
}
private InjectionNode innerGenerateProxyCode(InjectionNode injectionNode) {
AOPProxyAspect aopProxyAspect = injectionNode.getAspect(AOPProxyAspect.class);
JDefinedClass definedClass;
String proxyClassName = injectionNode.getClassName() + "_AOPProxy";
ASTInjectionAspect injectionAspect = injectionNode.getAspect(ASTInjectionAspect.class);
ConstructorInjectionPoint constructorInjectionPoint =
injectionAspect.getConstructorInjectionPoint();
ConstructorInjectionPoint proxyConstructorInjectionPoint =
new ConstructorInjectionPoint(ASTAccessModifier.PUBLIC);
try {
definedClass = codeModel._class(JMod.PUBLIC, proxyClassName, ClassType.CLASS);
annotateGeneratedClass(definedClass);
// extending injectionNode
definedClass._extends(codeModel.ref(injectionNode.getClassName()));
// copy constructor elements and add aop interceptors
JMethod constructor = definedClass.constructor(JMod.PUBLIC);
// converting exceptions into runtime exceptions
proxyConstructorInjectionPoint.addThrows(constructorInjectionPoint.getThrowsTypes());
for (ASTType throwType : constructorInjectionPoint.getThrowsTypes()) {
constructor._throws(codeModel.ref(throwType.getName()));
}
JBlock constructorBody = constructor.body();
List<JVar> superArguments = new ArrayList<JVar>();
for (InjectionNode node : constructorInjectionPoint.getInjectionNodes()) {
String paramName = namer.generateName(node);
JVar param = constructor.param(codeModel.ref(node.getClassName()), paramName);
superArguments.add(param);
proxyConstructorInjectionPoint.addInjectionNode(node);
}
// super construction
JInvocation constructorInvocation = constructorBody.invoke(SUPER_REF);
for (JVar paramArgument : superArguments) {
constructorInvocation.arg(paramArgument);
}
// method interceptors
Map<ASTMethod, Map<InjectionNode, JFieldVar>> interceptorFields =
new HashMap<ASTMethod, Map<InjectionNode, JFieldVar>>();
for (Map.Entry<ASTMethod, Set<InjectionNode>> methodInterceptorEntry :
aopProxyAspect.getMethodInterceptors().entrySet()) {
buildMethodInterceptor(
definedClass,
proxyConstructorInjectionPoint,
constructor,
constructorBody,
interceptorFields,
methodInterceptorEntry);
}
} catch (JClassAlreadyExistsException e) {
logger.error("JClassAlreadyExistsException while building AOP Proxy", e);
} catch (ClassNotFoundException e) {
logger.error("ClassNotFoundException while building AOP Proxy", e);
}
return buildProxyInjectionNode(
injectionNode, proxyClassName, injectionAspect, proxyConstructorInjectionPoint);
}
private void buildMethodInterceptor(
JDefinedClass definedClass,
ConstructorInjectionPoint proxyConstructorInjectionPoint,
JMethod constructor,
JBlock constructorBody,
Map<ASTMethod, Map<InjectionNode, JFieldVar>> interceptorFields,
Map.Entry<ASTMethod, Set<InjectionNode>> methodInterceptorEntry)
throws ClassNotFoundException {
ASTMethod method = methodInterceptorEntry.getKey();
if (method.getAccessModifier().equals(ASTAccessModifier.PRIVATE)) {
throw new TransfuseAnalysisException("Unable to provide AOP on private methods");
}
if (!interceptorFields.containsKey(methodInterceptorEntry.getKey())) {
interceptorFields.put(
methodInterceptorEntry.getKey(), new HashMap<InjectionNode, JFieldVar>());
}
Map<InjectionNode, JFieldVar> injectionNodeInstanceNameMap =
interceptorFields.get(methodInterceptorEntry.getKey());
// setup interceptor fields
for (InjectionNode interceptorInjectionNode : methodInterceptorEntry.getValue()) {
String interceptorInstanceName = namer.generateName(interceptorInjectionNode);
JFieldVar interceptorField =
definedClass.field(
JMod.PRIVATE,
codeModel.ref(interceptorInjectionNode.getClassName()),
interceptorInstanceName);
injectionNodeInstanceNameMap.put(interceptorInjectionNode, interceptorField);
JVar interceptorParam =
constructor.param(
codeModel.ref(interceptorInjectionNode.getClassName()),
namer.generateName(interceptorInjectionNode));
constructorBody.assign(interceptorField, interceptorParam);
proxyConstructorInjectionPoint.addInjectionNode(interceptorInjectionNode);
}
JType returnType = codeModel.parseType(method.getReturnType().getName());
JMethod methodDeclaration =
definedClass.method(
method.getAccessModifier().getCodeModelJMod(), returnType, method.getName());
JBlock body = methodDeclaration.body();
// define method parameter
Map<ASTParameter, JVar> parameterMap = new HashMap<ASTParameter, JVar>();
for (ASTParameter parameter : method.getParameters()) {
parameterMap.put(
parameter,
methodDeclaration.param(
JMod.FINAL,
codeModel.ref(parameter.getASTType().getName()),
namer.generateName(parameter.getASTType())));
}
// aop interceptor
Map<InjectionNode, JFieldVar> interceptorNameMap =
interceptorFields.get(methodInterceptorEntry.getKey());
JArray paramArray = JExpr.newArray(codeModel.ref(Object.class));
for (ASTParameter astParameter : method.getParameters()) {
paramArray.add(parameterMap.get(astParameter));
}
JInvocation interceptorInvocation =
buildInterceptorChain(
definedClass,
method,
parameterMap,
methodInterceptorEntry.getValue(),
interceptorNameMap)
.invoke("invoke");
interceptorInvocation.arg(paramArray);
if (method.getReturnType().equals(ASTVoidType.VOID)) {
body.add(interceptorInvocation);
} else {
body._return(JExpr.cast(returnType.boxify(), interceptorInvocation));
}
}
@Test
public void testBackLinkAnalysis() {
ASTType astType = astClassFactory.getType(A.class);
InjectionNode injectionNode = analyzer.analyze(astType, astType, analysisContext);
injectionNode.addAspect(VariableBuilder.class, variableInjectionBuilderProvider.get());
// A -> B && A -> E
assertEquals(1, countMethodInjectionPoints(injectionNode.getAspect(ASTInjectionAspect.class)));
MethodInjectionPoint bInjectionPoint =
injectionNode
.getAspect(ASTInjectionAspect.class)
.getGroups()
.get(1)
.getMethodInjectionPoints()
.iterator()
.next();
assertEquals(2, bInjectionPoint.getInjectionNodes().size());
// A -> B
InjectionNode bInjectionNode = bInjectionPoint.getInjectionNodes().get(0);
assertTrue(isProxyRequired(bInjectionNode));
assertEquals(BImpl.class.getCanonicalName(), bInjectionNode.getClassName());
// A -> E
InjectionNode eInjectionNode = bInjectionPoint.getInjectionNodes().get(1);
assertFalse(isProxyRequired(eInjectionNode));
assertEquals(E.class.getCanonicalName(), eInjectionNode.getClassName());
// B -> C
assertEquals(1, countFieldInjectionPoints(bInjectionNode.getAspect(ASTInjectionAspect.class)));
FieldInjectionPoint cInjectionPoint =
bInjectionNode
.getAspect(ASTInjectionAspect.class)
.getGroups()
.get(1)
.getFieldInjectionPoints()
.iterator()
.next();
InjectionNode cInjectionNode = cInjectionPoint.getInjectionNode();
assertFalse(isProxyRequired(cInjectionNode));
assertEquals(C.class.getCanonicalName(), cInjectionNode.getClassName());
// B -> F
ConstructorInjectionPoint fNonBackLinkInjectionPoint =
bInjectionNode.getAspect(ASTInjectionAspect.class).getConstructorInjectionPoint();
assertEquals(1, fNonBackLinkInjectionPoint.getInjectionNodes().size());
InjectionNode fInjectionNode = fNonBackLinkInjectionPoint.getInjectionNodes().get(0);
assertFalse(isProxyRequired(fInjectionNode));
assertEquals(F.class.getCanonicalName(), fInjectionNode.getClassName());
// E -> F
ConstructorInjectionPoint fNonBackLinkInjectionPoint2 =
eInjectionNode.getAspect(ASTInjectionAspect.class).getConstructorInjectionPoint();
assertEquals(1, fNonBackLinkInjectionPoint2.getInjectionNodes().size());
InjectionNode fInjectionNode2 = fNonBackLinkInjectionPoint2.getInjectionNodes().get(0);
assertFalse(isProxyRequired(fInjectionNode2));
// C -> D
assertEquals(1, countFieldInjectionPoints(cInjectionNode.getAspect(ASTInjectionAspect.class)));
FieldInjectionPoint dInjectionPoint =
cInjectionNode
.getAspect(ASTInjectionAspect.class)
.getGroups()
.get(1)
.getFieldInjectionPoints()
.iterator()
.next();
InjectionNode dInjectionNode = dInjectionPoint.getInjectionNode();
assertFalse(isProxyRequired(dInjectionNode));
assertEquals(D.class.getCanonicalName(), dInjectionNode.getClassName());
// D -> B back link
ConstructorInjectionPoint bBackLinkInjectionPoint =
dInjectionNode.getAspect(ASTInjectionAspect.class).getConstructorInjectionPoint();
assertEquals(1, bBackLinkInjectionPoint.getInjectionNodes().size());
InjectionNode bBackLinkInjectionNode = bBackLinkInjectionPoint.getInjectionNodes().get(0);
assertEquals(BImpl.class.getCanonicalName(), bBackLinkInjectionNode.getClassName());
assertTrue(isProxyRequired(bBackLinkInjectionNode));
// B -> F and E -> F difference
assertNotSame(fInjectionNode, fInjectionNode2);
assertFalse(fInjectionNode.equals(fInjectionNode2));
}