Using SubSonic, how to add a field to a pre-defined class? - subsonic

I've got a SubSonic DAL - works great.
Two classes: TblReceipt and TblReceiptLineItems.
I can create a parallel class of TblReceipt, but seems like a waste, so here's what I need to do:
Have a Class TblReceipt with one additional member, "ReceiptLineItems" - which is simply an ArrayList. This array list will be populated with TblReceiptLineItems types.
So for each Receipt, there are 1..* ReceiptLineItems stored in the array, then the whole thing is serialized.
How can I accomplish this with my existing SubSonic DAL?
A quick code sample would be useful too.
Thank you.

Use a partial class. All classes in Subsonic are defined as partial. What you do is (in a separate file than the one that is generated by Subsonic), you create another part of the partial class with the additional property.
Option 2 here:
http://jamesewelch.wordpress.com/2008/09/24/how-to-use-custom-audit-fields-with-subsonic/

Related

JAXB how to remove anything from JDefinedClass

i am using jaxb to generate code from an xsd.
The generated code contains a lot of annotations; for classes and fields.
I am trying to use com.sun.tools.internal.xjc.Plugin to modify the generated code.
In the plugin run() method we are given an Outline class from which we can get ClassOutline. ClassOutline has an JDefinedClass final member which has the info about actual class which will be generated.
If i want to add anything, there are apis in JDefinedClass which can be used. But if i want to remove something, there is no way.
e.g. i cannot clear annotations, because the JDefinedClass.annotations() method returns an UnmodifiableCollection. so i cannot clear it or remove anything from it.
i tried to create another JDefinedClass by invoking the _class method but the ClassOutline.implClass variable is final, so i cannot set it.
how to get a JDefinedClass which does not have any annotations?
is there another phase of code generation which i can trap into to really control the generation of JDefinedClass?
The code model is, indeed mostly "write only". But, speaking of annotations, you have probably missed the methods like com.sun.codemodel.JDefinedClass.removeAnnotation(JAnnotationUse) and com.sun.codemodel.JMethod.removeAnnotation(JAnnotationUse) (implemented from com.sun.codemodel.JAnnotatable.removeAnnotation(JAnnotationUse)).
So they're there. You can remove annotations with the normal CodeModel API.
As I can see, you can also remove fields and methods from classes. So what exactly are you missing?
JDefinedClass.annotations() It return an unmodifiable collection object and you cannot modify them.
So work around for this, you can restrict annotation addition/deletion at class and field level before building JCodeModel.
You need to create a custom Jackson2Annotator class which extends Jackson2Annotator and override their methods according to your requirement.
Following are few methods which are being used for specific type of annotation property:
propertyOrder(OTB JsonPropertyOrder)
propertyInclusion(OTB JsonInclude)
propertyField(can be used for custom defined annotation at field level)
More you can discover by looking Jackson2Annotator class what fit into your need.

JXB How to use different strategies of code generation

usually, JAXB is used to generate code from an xsd, which generates java classes for xsd complexType with annotations to convert it to xml and vice-versa.
I am trying to achieve something different. I want, to generate a data mapper class for each such xsd element. The mapper will map each field of the generated class with values from another datatype (say from database, or other stream)
so i need to: for every user-defined datatype in xsd, add a method in a DataMapper class map-<XSD-ComplexDataType-Class>() and generate method body.
to achieve this, i think it is not possible to generate this class in a Plugin extending com.sun.tools.internal.xjc.Plugin as in the run method, i wont be able to create a new JDefinedClass
is there any way to add a hook method before Model invokes Plugins ?
thanks,
There are a few things you can do. In my other answer I specificaly meant these:
In a plugin you can write and set your own com.sun.tools.xjc.generator.bean.field.FieldRendererFactory. Field renderers generate a FieldOutlines from CPropertyInfos. This is a step between the model and the outline. So if you want different code generated out of the model, consider implementing your own FieldRendererFactory. You can register a FieldRendererFactory via XJC plugin (see Options.setFieldRendererFactory(...)).
On the class level, you can write your own com.sun.tools.xjc.generator.bean.BeanGenerator and use it for code generation.
You can just use model and generate the code completely on your own. I do this in Jsonix when I produce JavaScript mappings for XML<->JSON.
As for your specific task, I would actually just postprocess the code model in the run method of your plugin. You have everything there - the model, the outline and also the code model (see outline.getCodeModel()). And you can definitely create your JDefinedClasses there, the code model exists already.

Extending a JOOQ Table class

I have a 'document' table (very original) that I need to dynamically subset at runtime so that my API consumers can't see data that isn't legal to view given some temporal constraints between the application/database. JOOQ created me a nice auto-gen Document class that represents this table.
Ideally, I'd like to create an anonymous subclass of Document that actually translates to
SELECT document.* FROM document, other_table
WHERE document.id = other_table.doc_id AND other_table.foo = 'bar'
Note that bar is dynamic at runtime hence the desire to extend it anonymously. I can extend the Document class anonymously and everything looks great to my API consumers, but I can't figure out how to actually restrict the data. accept() is final and toSQL doesn't seem to have any effect.
If this isn't possible and I need to extend CustomTable, what method do I override to provide my custom SQL? The JOOQ docs say to override accept(), but that method is marked final in TableImpl, which CustomTable extends from. This is on JOOQ 3.5.3.
Thanks,
Kyle
UPDATE
I built 3.5.4 from source after removing the "final" modifier on TableImpl.accept() and was able to do exactly what I wanted. Given that the docs imply I should be able to override accept perhaps it's just a simple matter of an erroneous final declaration.
Maybe you can implement one of the interfaces
TableLike (and delegate all methods to a JOOQ implementation instance) such as TableImpl (dynamic field using a HashMap to store the Fields?)
Implement the Field interface (and make it dynamic)
Anyway you will need to remind that there are different phases while JOOQ builds the query, binds values, executes it etc. You should probably avoid changing the "foo" Field when starting to build a query.
It's been a while since I worked with JOOQ. My team ended up building a customized JOOQ. Another (dirty) trick to hook into the JOOQ library was to use the same packages, as the protected identifier makes everything visible within the same package as well as to sub classes...

System.ComponentModel.BindingList: Add(object) vs. AddNew()

What is the difference between the System.ComponentModel.BindingList methods Add(object) and AddNew()? The MSDN documentation says this:
Add: Adds an object to the end of the Collection<T>.
AddNew: Adds a new item to the collection.
It seems like both methods add an item to the collection, but Add(object) does it in one shot whereas AddNew() is slightly more complicated. My tests with Add(object) seem to be working, but I want to know if I am using the correct method.
So what is the difference between these methods?
AddNew() creates the object for you (that's why it doesn't have a parameter).
It's designed to be used by grids, which don't know how to create a new object to pass to Add().
AddNew() is very handy (it’s the well-known Factory design pattern) when you implement a class derived of BindingList().
It allows your code to initialize new items with values that depend on the list itself - e.g. a foreign key to the parent object if the binding list contains a list of children.

Can we get declared properties of a Groovy class by its order?

I created a plain Groovy class (i.e Person class)with some properties. Now I want to get those declared attributes (which I've defined in my class) with their order, but I don't know how to do it.
I've tried to use Person.metaClass.getProperties() but it retrieves not only declared properties but also built-in Groovy ones.
Could you please help me on this: just get declared properties by its order when declaring.
Thank you so much!
I can't see a use case, but the compiler could reorder all fields declaration while creating bytecode. I'm pretty sure ordering is not a constraint on fields though it should mostly be the case for not modified/enhanced class
As per the JVM spec, generated fields should be marked SYNTHETIC (like generated methods) in the bytecode, so you can test with :
Person.getDeclaredFields().grep { !it.synthetic }
and filter the base Groovy fields like ClassInfo,metaClass and others beginning by __timestamp
But I'm not a specialist, there could be another way I don't think of
There was a question about this on the mailing list back in February of this year
The answer is, no. There is no way to get properties in the order they are declared in the class without doing some extra work.
You could parse the source file for the class, and generate an ordered list of property names from that
You could write a custom annotation, and annotate the fields with this annotation ie: #Order(1) String prop
You could make all of the classes where this matters implement an interface which forces them to have a method that returns the names of the properties in order.
Other than that, you probably want to have a re-think :-(

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