I am using Optaplanner with Quarkus, does anyone know if ProblemId can be accessed from ConstraintProvider? I'm using the SolverManager, and I would like to be able to fine-tune the Constraints based on the resolution request that uses parameters sent by the user and stored in H2. These parameters are stored with the ProblemId, and I would like to find them in the ConstraintProvider. Is this possible? Has anyone tried to do something similar?
A ConstraintProvider can write constraints based on any method of any problem fact or planning entity.
So it can do something with the #PlanningId annotated method of for example Lesson: from(Lesson.class).filter((lesson) -> lesson.getId() ...)
But I suspect what you want to do is #ConstraintConfiguration. See docs.
Related
I am working with GraphQL (in Java) and I would like to find a way to do the following:
I need the possibility to constantly adapt the GraphQL schema at runtime without restart. In particular I need to be able to add new fields to GraphQL types. Moreover I need the possibility to be able to write resolvers which can handle this dynamic schema.
I do not have example code yet, so just think of the simplest example (one GraphQL type with several fields that can all be of different type).
My problem is that I am quite new in GraphQL and I do not have a lot of experience with it. Of course I looked for a solution on the internet, but I did not find one yet (or just did not notice that I found it due to my lacking experience with GraphQL).
The only interesting discovery I made is this: exposing dynamic schemas with graphql . But I do not understand how this solution works because 1) I do not know how to reload the schema at runtime and 2) I do not know how to write the resolvers so that they can handle that dynamic schema.
So can anybody help me with my problem and/or can answer my questions regarding the link I found?
I am very thankful for every help, no matter how extensive it is. Like I told before, I am quite new in GraphQL. Therefore I would be also very thankful for links to examples (if possible), so that I can understand better.
Thank you very much in advance.
#userongithub0 you may take a look at GraphQL Schema Directives
And specifically on the rest directive
First of all, don't ever try to do that or use only if there're some very strict situations. Here's why:
A schema is like a contract between the front-end & backend & on change, it can lead to instability between both of them very quickly.
If you try to change the schema of GraphQL, it might fail to connect properly with your resolvers & consecutively with your database as well.
Whenever there's is a change in the schema the GraphQL server (the server handler, in general) needs to be restarted (recompile) & it will take time, hence results in high response time.
No matter what language you are using, you should always see it as a red flag. In my opinion, it will be a really bad practice.
I am working on a new project using spring data jdbc because it is very easy to handle and indeed splendid.
In my scenario i have three (maybe more in the future) types of projects. So my domain model could be easily modelled with plain old java objects using type inheritance.
First question:
As i am using spring data jdbc, is this way (inheritance) even supported like it is in JPA?
Second question - as addition to the first one:
I could not found anything regarding this within the official docs. So i am assuming there are good reasons why it is not supported. Speaking of that, may i be on the wrong track modelling entities with inheritance in general?
Currently Spring Data JDBC does not support inheritance.
The reason for this is that inheritance make things rather complicated and it was not at all clear what the correct approach is.
I have a couple of vague ideas how one might create something usable. Different repositories per type is one option, using a single type for persisting, but having some post processing to obtain the correct type upon reading is another one.
I am looking for information about how to create dynamic queries using the newer StreamInsight 2.1 reactive extensions model. Specifically, I would like to use the CreatQuery() method or something similar (within IQueryable) with IQStreamable. Within the workflow I am creating, this new query would be inserted into StreamInsight as a standing query. I have done quite a bit of research but have not found a solution. Also, most of the documentation appears to reference what is now a "legacy" adapter model. Any help would be appreciated.
What do you mean by "Dynamic Query"? Something similar to Dynamic Query Composition, where you could use the output of one query as a stream input into another query? If that's the case, you can use Subjects for this. Subjects allow you to have multiple publishers/subscribers for a stream and also provide the ability to attach/detach publishers and subscribers at runtime.
As far as I remember StreamInsights does not support that concept, the only way to archive that would be to use dynamic compilation to publish to StreamInsights query instance compiled based on dynamically generated code. That is quite possible.
I am using GATE in one of my applications and I have few queries related to Multi-tenancy. My requirements are as given below.
I have the keywords set, specific for each user and depending on
which user is signed in, I need to initialise gazetteer with the
applicable set of keywords.
At a given time there could be multiple users logging into my
application and I want to make sure that the multi-tenancy
approach will not be inefficient.
I don't want to store the keywords for each user in the .lst
file(s) but store it on a DB (mongo) and inject only at the
runtime.
I searched the web for few samples and though I found some thoughts on working with Processing Resource, I have no idea how the performance will be affected.
Your help is much appreciated.
Thanks in advance,
Sajith
That's an interesting use-case for a GATE gazetteer.
One thing I believe you should definitely do is add the user ID as a feature when you're creating the document. This way you'll be able to make your MongoDB query in a processing resource later on.
When you're processing the document, you have several options:
Create a custom PR which calls MongoDB and replicates the DefaultGazetteer code but with overwritten "init" method (or inherit or wrap it, haven't looked into much detail if that's possible). Instead of the default init method you should provide your list of keywords, then set the needed fields and call execute().
If you don't have too many keywords, create a custom PR (or groovy scripting PR) which calls MongoDB and does some simple regex search like the one in this thread.
They also suggest the stringsearch library in the comments. Then just use start and end indices to create Lookup annotations on your own.
You said you don't want that but still, several million words can be handled by both the default and the Hash gazetteer. Although, you should be careful as gate documents could be very memory-intensive if you have too many annotations - in your case Lookups for all user keywords.
Hope this helps.
I am working on a REST service which uses Spring 4.x. As per a requirement I have to produce several different views out of same object. Sample URIs:
To get full details of a location service: /services/locations/{id}/?q=view:full
To get summary of a location service: /services/locations/{id}/?q=view:summary
I have thought of two solutions for such problem:
1. Create different objects for different views.
2. Create same object, but filter out the fields based on some configuration (shown below)
location_summary_fields = field1, field2
location_detail_fields = field1, field2, field3
Could someone help me to understand what could be an ideal solution? I am not aware of any standard practice followed for this kind of problems.
Thanks,
NN
In my opinion the best option is to use separate POJOs for different views. It's a lot easier to document it (for example when you use some automated tools like Swagger). Also you've to remember that your application will change after some time, and then having one common POJO could make troubles - then you'll need to add one field to one service and don't expose it through another.
See this article on how google gson uses annotations to convert a Java Object representation to a json format : http://www.javacreed.com/gson-annotations-example/
Since you want two different representations for the same object you could roll your own
toJson method as follows :
a) Annotate each field of you model with either #Summary, #Detail or #All
b) Implement a toJson() method that returns a json representation by examining the annotations for the fields and appropriately using them
If you need an XML representation same thing, except you would have a toXML().