fix for 169432 - allow @DeclareParents with no impl if the targets implement the interface correctly

weaver/src/org/aspectj/weaver/bcel/AtAjAttributes.java

@@ -742,28 +742,27 @@ public class AtAjAttributes {
                     for (int i = 0; i < methods.length; i++) {
                         ResolvedMember method = (ResolvedMember)methods[i];
                         if (method.isAbstract()) {
-                            if (defaultImplClassName == null) {
-                                // non marker interface with no default impl provided
-                                reportError("@DeclareParents: used with a non marker interface and no defaultImpl=\"...\" provided", struct);
-                                return false;
-                            }
+                        // moved to be detected at weave time if the target doesnt implement the methods
+//                            if (defaultImplClassName == null) {
+//                                // non marker interface with no default impl provided
+//                                reportError("@DeclareParents: used with a non marker interface and no defaultImpl=\"...\" provided", struct);
+//                                return false;
+//                            }
                             hasAtLeastOneMethod = true;
-
-                            struct.ajAttributes.add(
-                                    new AjAttribute.TypeMunger(
-                                            new MethodDelegateTypeMunger(
-                                                method,
-                                                struct.enclosingType,
-                                                defaultImplClassName,
-                                                typePattern
-                                            )
-                                    )
-                            );
+                            MethodDelegateTypeMunger mdtm = 
+                                new MethodDelegateTypeMunger(
+                                    method,
+                                    struct.enclosingType,
+                                    defaultImplClassName,
+                                    typePattern
+                                );
+                            mdtm.setSourceLocation(struct.enclosingType.getSourceLocation());
+                            struct.ajAttributes.add(new AjAttribute.TypeMunger(mdtm));
                         }
                     }
                     // successfull so far, we thus need a bcel type munger to have
                     // a field hosting the mixin in the target type
-                    if (hasAtLeastOneMethod) {
+                    if (hasAtLeastOneMethod && defaultImplClassName!=null) {
                         struct.ajAttributes.add(
                                 new AjAttribute.TypeMunger(
                                         new MethodDelegateTypeMunger.FieldHostTypeMunger(

weaver/src/org/aspectj/weaver/bcel/BcelTypeMunger.java

@@ -1087,6 +1087,27 @@ public class BcelTypeMunger extends ConcreteTypeMunger {
 		clazz.addMethodGen(bridgeMethod);
 	}
 	
+	// Unlike toString() on a member, this does not include the declaring type
+	private String stringifyMember(ResolvedMember member) {
+		StringBuffer buf = new StringBuffer();
+    	buf.append(member.getReturnType().getName());
+    	buf.append(' ');
+   		buf.append(member.getName());
+    	if (member.getKind() != Member.FIELD) {
+    		buf.append("(");
+    		UnresolvedType[] params = member.getParameterTypes();
+            if (params.length != 0) {
+                buf.append(params[0]);
+        		for (int i=1, len = params.length; i < len; i++) {
+                    buf.append(", ");
+        		    buf.append(params[i].getName());
+        		}
+            }
+    		buf.append(")");
+    	}
+    	return buf.toString();
+	}
+	
     private boolean mungeMethodDelegate(BcelClassWeaver weaver, MethodDelegateTypeMunger munger) {
         ResolvedMember introduced = munger.getSignature();
 
@@ -1102,6 +1123,34 @@ public class BcelTypeMunger extends ConcreteTypeMunger {
 
         boolean shouldApply = munger.matches(weaver.getLazyClassGen().getType(), aspectType);
         if (shouldApply) {
+        	
+        	// If no implementation class was specified, the intention was that the types matching the pattern
+        	// already implemented the interface, let's check that now!
+        	if (munger.getImplClassName()==null) {
+        		boolean isOK = false;
+        		List/*LazyMethodGen*/ existingMethods = gen.getMethodGens();
+        		for (Iterator i = existingMethods.iterator(); i.hasNext() && !isOK;) {
+        		    LazyMethodGen m = (LazyMethodGen) i.next();
+        		    if (m.getName().equals(introduced.getName()) &&  
+        		        m.getParameterSignature().equals(introduced.getParameterSignature()) &&
+        		        m.getReturnType().equals(introduced.getReturnType())) {
+        		    	isOK = true;
+        		    }
+        		}        
+        		if (!isOK) {
+        			// the class does not implement this method, they needed to supply a default impl class
+        			IMessage msg = new Message("@DeclareParents: No defaultImpl was specified but the type '"+gen.getName()+
+        					"' does not implement the method '"+stringifyMember(introduced)+"' defined on the interface '"+introduced.getDeclaringType()+"'",
+        					weaver.getLazyClassGen().getType().getSourceLocation(),true,new ISourceLocation[]{munger.getSourceLocation()});
+        			weaver.getWorld().getMessageHandler().handleMessage(msg);
+        			return false;
+        		}
+        		
+        		return true;
+        	}
+        	
+        	
+        	
             LazyMethodGen mg = new LazyMethodGen(
                     introduced.getModifiers() - Modifier.ABSTRACT,
                     BcelWorld.makeBcelType(introduced.getReturnType()),