In our framework we have an interface with this method in the public API:
JaxbConfiguration newJaxbConfiguration(Options xjcOpts);
In the implementation, we do something like this:
import com.sun.tools.xjc.ModelLoader;
import com.sun.tools.xjc.Options;
import com.sun.tools.xjc.model.Model;
...
public JaxbConfiguration newJaxbConfiguration(Options xjcOpts) {
Model model = ModelLoader.load(xjcOpts, ...);
...
}
However, both OSGi and Java 9's jigsaw don't like that we use com.sun.tools.xjc.Options, not in our implementation and especially not in our public API interface.
How can we get rid of it?
The JDeps website lists some of the JDK internal APIs and the recommended way to replace their usage. However, the use of ModelLoader.load() is not mentioned. My guess is that this use case has not come up enough to get the attention of the JDeps team.
My recommendation would be to refactor this method so that
you pass in the data you're using to construct the Options argument, instead of passing in the Options argument
use that data to construct your JaxbConfiguration object instead of converting from the internal Model.
You don't mention what JaxbConfiguration is or what library it's from so it's hard for me to say exactly how to construct it. Anyway, this answer is about how to remove the use of the internal API. How to construct a JaxbConfiguration is probably a different question.
Related
Given a set of classes where it should not be forbidden to use certain APIs (for whatever reason).
For example, prohibiting Java 8 Streaming API, or calling a Builder inner class because you want to force the usage of loops and constructors for particular classes.
The critical part is that you do not know the ownerName beforehand and there is no callMethod(methodName) where I could coarse-grainy disallow calling stream() or build() methods.
Any ideas?
You can compose powerful ArchRules using predicates instead of the fluent API; in your case with
.callMethodWhere(DescribedPredicate<? super JavaMethodCall> predicate).
To prevent the usage of someCollection.stream(), you could start with HasName.Predicates.name:
noClasses().should().callMethodWhere(name("stream"))
To avoid false-positives, the rule should probably become more specific.
ArchUnit ships lots of useful pre-defined predicates; you just need to find them (and possibly deal with their covariant parameter types via DescribedPredicate.forSubtype):
noClasses().should().callMethodWhere(target(
name("stream").<CodeUnitCallTarget>forSubtype().and(
owner(assignableTo(Collection.class)).<CodeUnitCallTarget>forSubtype().and(
rawParameterTypes(new Class[0])
)
)
))
I personally find it simpler to define a custom predicate instead (e.g. using
DescribedPredicate.describe):
noClasses().should().callMethodWhere(target(describe("is Collection.stream()",
target -> "stream".equals(target.getName()) &&
target.getOwner().isAssignableTo(Collection.class) &&
target.getParameterTypes().isEmpty()
)))
FYI: My solution uses the following imports:
import static com.tngtech.archunit.base.DescribedPredicate.describe;
import static com.tngtech.archunit.core.domain.JavaCall.Predicates.target;
import static com.tngtech.archunit.core.domain.JavaClass.Predicates.assignableTo;
import static com.tngtech.archunit.core.domain.properties.HasName.Predicates.name;
import static com.tngtech.archunit.core.domain.properties.HasOwner.Predicates.With.owner;
import static com.tngtech.archunit.core.domain.properties.HasParameterTypes.Predicates.rawParameterTypes;
import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClasses;
I am mocking an interface array which throws java.lang.IllegalArgumentException: Cannot subclass final class class.
Following are the changes I did.
Added the following annotations at class level in this exact order:
#Runwith(PowerMockRunner.class)
#PrepareForTest({ Array1[].class, Array2[].class })
Inside the class I am doing like this:
Array1[] test1= PowerMockito.mock(Array1[].class);
Array2[] test2= PowerMockito.mock(Array2[].class);
and inside test method:
Mockito.when(staticclass.somemethod()).thenReturn(test1);
Mockito.when(staticclass.somediffmethod()).thenReturn(test2);
Basically I need to mock an array of interfaces.
Any help would be appreciated.
Opening up another perspective on your problem: I think you are getting unit tests wrong.
You only use mocking frameworks in order to control the behavior of individual objects that you provide to your code under test. But there is no sense in mocking an array of something.
When your "class under test" needs to deal with some array, list, map, whatever, then you provide an array, a list, or a map to it - you just make sure that the elements within that array/collection ... are as you need them. Maybe the array is empty for one test, maybe it contains a null for another test, and maybe it contains a mocked object for a third test.
Meaning - you don't do:
SomeInterface[] test1 = PowerMock.mock() ...
Instead you do:
SomeInterface[] test1 = new SomeInterface[] { PowerMock.mock(SomeInterface.class) };
And allow for some notes:
At least in your code, it looks like you called your interface "Array1" and "Array2". That is highly misleading. Give interfaces names that say what their behavior is about. The fact that you later create arrays containing objects of that interface ... doesn't matter at all!
Unless you have good reasons - consider not using PowerMock. PowerMock relies on byte-code manipulation; and can simply cause a lot of problems. In most situations, people wrote untestable code; and then they turn to PowerMock to somehow test that. But the correct answer is to rework that broken design, and to use a mocking framework that comes without "power" in its name. You can watch those videos giving you lengthy explanations how to write testable code!
I have a library of domain objects which need to be used in the project, however we've found a couple of the classes haven't got an equals or hashCode method implemented.
I'm looking for the simplest (and Grooviest) way to add those methods. Obviously I could create a subclass which only adds the methods, but this would be confusing for developers used to the library and would mean we'd have to refactor existing code.
It is not possible to get the source changed (currently).
If I could edit the class I would just use the #EqualsAndHashCode annotation to carry out an AST transformation (at compile time?), but I can't find a way to instruct the compiler to carry out the transformation on a class which I can't directly annotate.
I'm currently trying to work up an example using the ExpandoMetaClass, so I'd do something like:
MySuperClass.metaClass.hashCode = { ->
// Add dynamic hashCode calculation bits here
}
MySuperClass.metaClass.equals = { ->
// Add dynamic hashCode calculation bits here
}
I don't really want to hand-code the hashCode/equals methods for each class, so I'm looking for something dyamic (like #EqualsAndHashCode) which will work with this.
Am I on the right track? Is there a groovier way?
AST Transforms are only applied at compile time, so you'll get no help from the likes of #EqualsAndHashCode. MetaClass hacks are going to be your only option. That said, there are more-elegant ways to impose MetaClass behavior.
Shameless Self Plug I did a talk about this kind of stuff last year at SpringOne 2GX: http://www.infoq.com/presentations/groovy-app-architecture
In short, you might find benefit in creating extensions (unless you're in Grails) - http://mrhaki.blogspot.com/2013/01/groovy-goodness-adding-extra-methods.html, or by explicitly adding mixins - http://groovy.codehaus.org/Runtime+mixins ... But in general, these are just cleaner ways to do the exact same thing you're already doing.
What I need: a class with two parents, which are ContextBoundObject and another class.
Why: I need to access the ContextBoundOject to log the method calls.
Composition works? As of now, no (types are not recognized, among other things).
Are other ways to do this? Yes, but not so automatable and without third-party components (maybe a T4 could do, but I'm no expert).
A more detailed explanation.
I need to extend System classes (some of which have already MarshalByRefObject (which is the parent of ContextBoundObject) for parent, for example ServiceBase and FileSystemWatcher, and some not, for example Exception and Timer) to access some inner workings of the framework, so I can log method calls (for now; in future it may change).
If I use this way I only have to add a class name to the object I want to log, instead of adding the logging calls to every method, but obviously I can't do this:
public class MyService:ServiceBase,ContextBoundObject,IDisposable{
public MyService(){}
public Dispose(){}
}
so one could try the usual solution, interfaces, but then if I call Run as in:
ServiceBase.Run(new MyService());
using a hypotethical interface IServiceBase it wouldn't work, because the type ServiceBase is not castable to IServiceBase -- it doesn't inherit from any interface. The problem is even worse with exceptions: throw only accepts a type descending from Exception.
The reverse, producing a IContextBoundObject interface, doesn't seem to work either: the logging mechanism doesn't work by methods, so I don't need to implement any, just an attribute and some small internal classes (and inheriting from ContextBoundObject, not even from MarshalByRefObject, which the metadata present as practically the same).
From what I see, extending from ContextBoundObject puts the extended class in a Proxy (probably because in this way the method calls use SyncProcessMessage(IMessage) and so can be intercepted and logged), maybe there's a way to do it without inheritance, or maybe there could be pre or post compiling techniques available for surrounding methods with logging calls (like T4 Text Templates), I don't know.
If someone wants to give this a look, I used a customized version of MSTestExtentions in my program to do the logging (of the method calls).
Any ideas are appreciated. There could be the need for more explanations, just ask.
Logging method calls is usually done using attributes to annotate classes or methods for which you want to have logging enabled. This is called Aspect Oriented Programming.
For this to work, you need a software that understands those attributes and post-processes your assembly by adding the necessary code to the methods / classes that have been annotated.
For C# there exists PostSharp. See here for an introduction.
Experimenting with proxies I found a way that apparently logs explicit calls.
Essentially I create a RealProxy like in example in the msdn, then obtain the TransparentProxy and use that as the normal object.
The logging is done in the Invoke method overridden in the customized RealProxy class.
static void Main(){
...
var ServiceClassProxy=new ServiceRealProxy(typeof(AServiceBaseClass),new object[]{/*args*/});
aServiceInstance=(AServiceBaseClass)ServiceClassProxy.GetTransparentProxy();
ServiceBase.Run(aServiceInstance);
...
}
In the proxy class the Invoke will be done like this:
class ServiceRealProxy:RealProxy{
...
[SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags=SecurityPermissionFlag.Infrastructure)]
public override IMessage Invoke(IMessage myIMessage){
// remember to set the "__Uri" property you get in the constructor
...
/* logging before */
myReturnMessage = ChannelServices.SyncDispatchMessage(myIMessage);
/* logging after */
...
return myReturnMessage;
// it could be useful making a switch for all the derived types from IMessage; I see 18 of them, from
// System.Runtime.Remoting.Messaging.ConstructionCall
// ... to
// System.Runtime.Remoting.Messaging.TransitionCall
}
...
}
I have still to investigate extensively, but the logging happened. This isn't an answer to my original problem because I have still to test this on classes that don't inherit from MarshalByRefObject.
I fell in love with Groovy and try to use it more and more. Now I have to work with Oracle Forms Jdapi library. When working with this library, you write a lot of code like this:
JdapiIterator progIterator = getWorkForm().getProgramUnits();
while(progIterator.hasNext()) {
ProgramUnit currProgUnit = (ProgramUnit) progIterator.next();
...
}
and of cource I would like to write
getWorkForm().programUnits.each {
...
}
However, I never wrote a Groovy interface to an existing Java library and need some assistance. I know about Groovy 2.0's extension methods, but in that case I am thinking about a class with the same name in a different namespace which delegates only to the functions I would like to keep.
What is the best approach for providing the each functionality, but also all other closures applicable for collections? I would appreciate if you point me in the right direction!
The only method you need to provide is the iterator() method. You then get all of the Groovy Object iteration methods (each(), find(), any(), every(), collect(), ...) for free!