I'm having some serious troubles getting a Windows Phone 7.5 class library to load into the WP Unit Test Framework. It internally calls GetExportedTypes() on my assembly which throws a ReflectionTypeLoadException that doesn't contain any details. Its message is "ReflectionTypeLoadException" and its LoaderExceptions is null ("Could not evaluate expression"). The assembly is not using any 3rd party assemblies. If I create a separate WP7 app and do the same thing, I get the same results. I'm a very experienced Reflection user, but the lack of any detailed errors has brought my research to a complete halt. Just for completeness, it's the Windows Phone version of Fluent Assertions.
What about the Types array on the exception? Does it contain values? If so, does it also contain nulls? If so, you can find out which classes failed to load: You know all classes in the assembly and you know which classes loaded correctly. Those that are missing are the classes that couldn't be loaded. Maybe this info gives some clues.
This answer is based on the documentation, especially these bits:
From the Remarks of the LoaderExceptions property:
The LoaderExceptions property retrieves an array of type Exception that is parallel to the Types array. This array will contain null values whenever reflection cannot load a class.
And from the documentation of the Types property:
An array of type Type containing the classes that were defined in the module and loaded. This array can contain some null values.
I've found it! #GeertvanHorrik pointed me at a blog post he recently wrote. I was using an covariant interface (using the out parameter) which the runtime (!) doesn't support. Why the compiler does not protect me from that is a big mystery (and a huge disappointment) to me
Related
I read a blog post and there was a sentence like this
"In Axon, there are constraints that require the package structure of the Event classes to be identical.
So even the same class, if the package is different, an error can occur."
And for this reason, he recommends using a multi-module structure.
is that true? I'm looking at the references and trying to find something like this, but I can't.
This point is indeed true, #YongD.
Axon Framework, when serializing any of your objects, will store the serialized format and the type. The serialized format that's stored most often is a byte[] of either XML or JSON. Which of the two depends on whether you have configured the XStreamSerializer or the JacksonSerializer.
So next to the serialized data, we have the type. The type, by default, would be the fully qualified class name and an optional revision number. Without the fully qualified class name, the serializer wouldn't know how to deserialize your data back into the required format. The package name is part of the FQCN, having different package names for conceptually the same class might cause issues upon deserialization.
This is why in sample projects provided by AxonIQ, you will always see all the messages belong to a core-api or api package or module. Already having this separation will allow for easier extraction of services into microservices at a later stage.
I'm currently studying UFT. I encountered this: I have one object, which is a textbox field on my repository. I used that specific object twice on my script. The warning then occurs. "The object was not found using the test object description. Check the object's properties." May I know what to do so that warning will no longer occur?
This warning means that UFT was not able to identify the object using the primary description it stored and that a fallback method called Smart Identification was used.
This means that the identification properties that you're currently using (either Object Repository or descriptive programming) are out of sync with your web application and it's recommended that you update the description (perhaps by adding regular expressions).
The report should list which properties where used by Smart Identification and which were skipped), this may be a good starting point to choosing your description.
I'm attempting to create a T4 template that generates source code for calling stored procedures that are contained in another project in my solution. I am able to successfully enumerate the .sql files in the solution, add them to a TSqlModel, and use that model to retrieve the list of stored procedures as TSqlObject instances. Now, I need to enumerate the parameters for each stored procedure, and this is where I'm getting hung up.
When I debug my template, I can see that the TSqlObject instances have a ContextObject property, and this property contains, among other things, the list of parameters that I need to generate my code. When I attempt to access this property from my template, however, the compiler complains that the property doesn't exist:
Error 1 Compiling transformation: 'Microsoft.SqlServer.Dac.Model.TSqlObject' does not contain a definition for 'ContextObject' and no extension method 'ContextObject' accepting a first argument of type 'Microsoft.SqlServer.Dac.Model.TSqlObject' could be found (are you missing a using directive or an assembly reference?) d:\Code\cs\test_sproccodegen\CallingProject\sproc_template.tt 34 111 CallingProject
I can definitely access this ContextObject property from the Immediate window while debugging, but it is not available at compile time.
What am I doing wrong?
The property isn't listed in the API, which probably means it's internal or private. Only public and protected accessible members are included in the docs.
Checking it out in JustDecompile, you can see it is, in fact, internal.
That's an internal method as mentioned by Will in the question comments. You should use the public APIs instead. The following documenation should help you get started:
Model API Reference
Public Model Tutorial
Dac samples project. There aren't any T4 template examples but it has a lot of examples of querying and even manipulating the model. You just need to put that in T4 template form.
Is it possible to get an instance of java.lang.reflect.Method by using the new method reference feature of Java 8?
That way I would have a compile time check and refactoring would be also easier. Also, I wouldn't need to catch the exceptions (which shouldn't been thrown after all).
Short answer: No.
You will get a lambda of that method, not a java.lang.reflect.Method. You do not know the name of the method. Just as you can not have a reference to a "property" of a java bean.
You can have a reference to the getter or setter but that is also a lambda and you do not know the actual name.
In any case you'd have to provide the name as a String and that can't be checked by the compiler. I also tried this but failed. It simply can't be done unless you write something that checks the javacode/bytecode. But there are tools that do that.
Maybe the Criteria API could be used for that, but it depends on the requirements.
http://docs.oracle.com/javaee/6/tutorial/doc/gjitv.html
There you'd have a SingularAttribute or similar field on a "metamodel" and then the regular java compiler can check the (generic) type of it.
I'm throwing this out in case someone has encountered this before.
When creating DesignData for use within the WPF designer, I get one of two errors:
Object does not match target type.
at System.Reflection.RuntimeMethodInfo.CheckConsistency(Object
target)
(SNIP)
at Microsoft.Expression.DesignModel.InstanceBuilders.ClrObjectInstanceBuilder. UpdateProperty(IInstanceBuilderContext
context, ViewNode viewNode, IProperty
propertyKey, DocumentNode valueNode)
The other one is a little more informative:
The value "_.di0.MyProjectLol.MyType"
is not of type "MyProjectLol.MyType"
and cannot be used in this generic
collection.
at
System.ThrowHelper.ThrowWrongValueTypeArgumentException(Object
value, Type targetType)
(SNIP)
at Microsoft.Expression.DesignModel.InstanceBuilders.ClrObjectInstanceBuilder.
InstantiateChildren(IInstanceBuilderContext
context, ViewNode viewNode,
DocumentCompositeNode compositeNode,
Boolean isNewInstance)
When debugging, I can see that there is a dynamic assembly that is loaded with proxy-ish types that look like mine but, obviously, are not. This assembly is called Blend_RuntimeGeneratedTypeAssembly(Guid goes here). When attempting to load types in this assembly, it throws a type load exception for a number of them. So, some types get proxied, some types are left as God and I intended, and when they mix unnatural acts occur.
For example, the type "Foo" might get a proxy created, but no other types do (TypeLoadExceptions). Then the designer tries to hand one of my real types the proxy (helped by the fact that xaml serialization likes to cast collections to IList, thus shitting on type safety) and you get one of the above exceptions.
I have spent half a week trying to fix this. I've tried a hundred different things, but I can't figure out exactly what is causing it to fail. Suggestions are welcome, TIA.
Solution in two parts:
1) Ensure VS is fully updated. At this point, it means installing the Silverlight 4 tools for Visual Studio 2010. They include the latest updates to the WPF designer. If you're reading this off in the distant future, ignore this one.
2) Hit the properties for your design data files. Clear out "Custom Tool", and set the "Build Action" to either "DesignData" or "DesignTimeDataWithDesignTimeCreatableTypes".
DesignData means that your types cannot be deserialized from xaml directly (due to dependencies or the such), so the designer attempts to create mocks for those types and presents the mocks to your design surface.
DesignTimeDataWithDesignTimeCreatableTypes means that the designer will load your assemblies and deserialize the xaml directly into your types without creating mocks.
This can also be caused by a certain combination of situations that, when combined, cause deserialization to fail.
Essentially if you have
A custom collection, or a collection that doesn't implement IList
That is exposed as a property on your type
Which is defined in a different assembly
you can get this error message as well.
It is very important that your collection property types implement IList (the non-generic one) if you want to serialize them to and from xaml!