I am to using the CacheJdbcPojoStoreFactory
I want to have a VARCHAR field in the database which maps to an Enum in Java.
The way I am trying to achieve this is something like the following. I want the application code to work with the enum, but the persistence to use the string so that it is human readable in the database. I do not want to use int values in the database.
This seems to work fine for creating new objects, but not for reading them out. It seems that it tries to set the field directly, and the setter (setSideAsString) is not called. Of course there is no field called sideAsString. Should this work? Any suggestions?
Here is the code excerpt
In some application code I would do something like
trade.setSide(OrderSide.Buy)
And this will persist fine. I can read "Buy" in the side column as a VARCHAR.
In Trade
private OrderSide side; // OrderSide is an enum with Buy,Sell
public OrderSide getSide() {
return side;
}
public void setSide(OrderSide side) {
this.side = side;
}
public String getSideAsString() {
return this.side.name();
}
public void setSideAsString(String s) {
this.side = OrderSide.valueOf(s);
}
Now when configuring the store, I do this
Collection<JdbcTypeField> vals = new ArrayList<>();
vals.add(new JdbcTypeField(Types.VARCHAR, "side", String.class, "sideAsString"));
After a clean start, If I query Trade using Ignite SQL query, and call trade.getSide() it will be null. Other (directly mapped) columns are fine.
Thanks,
Gordon
BinaryMarshaller deserialize only fields which used in query.
Please try to use OptimizedMarshaller:
IgniteConfiguration cfg = new IgniteConfiguration();
...
cfg.setMarshaller(new OptimizedMarshaller());
Here's the ticket for support enum mapping in CacheJdbcPojoStore.
Related
Is there any API using which I can get graphTraversalName to graphName mapping defined in the script?
I am using the below messy code but it's error-prone if both graphs are using the same underlying storage.
Map<String, String> graphTraversalToNameMap = new ConcurrentHashMap<String, String>();
while(traversalSourceIterator.hasNext()){
String traversalSource = traversalSourceIterator.next();
String currentGraphString = ( (GraphTraversalSource) graphManager.getAsBindings().get(traversalSource)).getGraph().toString();
graphNameTraversalMap.put(currentGraphString, traversalSource);
}
Iterator<String> graphNamesIterator = graphManager.getGraphNames().iterator();
while(graphNamesIterator.hasNext()){
String graphName = graphNamesIterator.next();
String currentGraphString = graphManager.getGraph(graphName).toString();
String traversalSource = graphNameTraversalMap.get(currentGraphString);
graphTraversalToNameMap.put(traversalSource, graphName);
}
Does gremlinExecutor.getScriptEngineManager().getBindings().entrySet() provide order guarantee? I can iterate over this and populate my map
Is there any API using which I can get graphTraversalName to graphName mapping defined in the script?
No. They share the same namespace in Gremlin Server so the relationship gets lost programmatically. You would need to do something like what you are doing but I wouldn't rely on toString() of a Graph for equality. Perhaps use the Graph instance itself? Although that might not work either depending on your situation and what you want for equality as you could have two different Graph configurations pointed at the same data and want to resolve those as the same graph. I'm also not sure that any approach will work generally for all graph systems. Anyway, I think I'd experiment with using Map<Graph, String> graphTraversalToNameMap for your case and see how that goes.
Does gremlinExecutor.getScriptEngineManager().getBindings().entrySet() provide order guarantee?
No as it is backed by a ConcurrentHashMap. You would have to provide your own order.
Underlying storage details can be obtained from the configuration object and can be used for the mapping, sample code:
public class GraphTraversalMappingUtil {
public static void populateGraphTraversalToNameMapping(GraphManager graphManager){
if(graphTraversalToNameMap.size() != 0){
return;
}
Iterator<String> traversalSourceIterator = graphManager.getTraversalSourceNames().iterator();
Map<StorageBackendKey, String> storageKeyToTraversalMap = new HashMap<StorageBackendKey, String>();
while(traversalSourceIterator.hasNext()){
String traversalSource = traversalSourceIterator.next();
StorageBackendKey key = new StorageBackendKey(
graphManager.getTraversalSource(traversalSource).getGraph().configuration());
storageKeyToTraversalMap.put(key, traversalSource);
}
Iterator<String> graphNamesIterator = graphManager.getGraphNames().iterator();
while(graphNamesIterator.hasNext()) {
String graphName = graphNamesIterator.next();
StorageBackendKey key = new StorageBackendKey(
graphManager.getGraph(graphName).configuration());
graphTraversalToNameMap.put(storageKeyToTraversalMap.get(key), graphName);
}
}
}
For full code, refer: https://pastebin.com/7m8hi53p
I am using Apache Ignite as the back-end data store in a SpringBoot Application.
I have a requirement where I need to get all the entities whose name matches one of the names from a set of names.
Hence i am trying to get it implemented using a #Query configuration and a method named findAllByName(Iterable<String> names)as below:
Here on the Query, I am trying to use the 'IN' clause and want to pass an array of names as an input to the 'IN' clause.
#RepositoryConfig(cacheName = "Category")
public interface CategoryRepository extends IgniteRepository<Category, Long>
{
List<Category> findByName(String name);
#Query("SELECT * FROM Category WHERE name IN ( ? )")
Iterable<Category> findAllByName(Iterable<String> names); // this method always returns empty list .
}
In this the method findAllByName always returns empty list, even when ignite has Categories for which the name field matches the data passed in the query.
I am unable to figure out if there is a problem with the Syntax or the query of the method signature or the parameters.
Please try using String[] names instead for supplying parameters.
UPDATE: I have just checked the source, and we don't have tests for such scenario. It means that you're on uncharted territory even if it is somehow possible to get to work.
Otherwise looks unsupported currently.
I know your question is more specific to Spring Data Ignite feature. However, as an alternate, you can achieve it using the SqlQuery abstraction of Ignite.
You will form your query like this. I have pasted the sample below with custom sql function inSet that you will write. Also, the below tells how this is used in your sql.
IgniteCache<String, MyRecord> cache = this.ignite
.cache(this.environment.getProperty(Cache.CACHE_NAME));
String sql = "from “my-ignite-cache”.MyRecord WHERE
MyRecord.city=? AND inSet(?, MyRecord.flight)"
SqlQuery<String, MyRecord> sqlQuery = new SqlQuery<>(MyRecord.class,
sql);
sqlQuery.setArgs(MyCity, [Flight1, Flight2 ] );
QueryCursor<Entry<String, MyRecord>> resultCursor = cache.query(sqlQuery);
You can iterate the result cursor to do something meaningful from the extracted data.
resultCursor.forEach(e -> {
MyRecord record = e.getValue();
// do something with result
});
Below is the Ignite Custom Sql function which is used in the above Query - this will help in replicating the IN clause feature.
#QuerySqlFunction
public static boolean inSet(List<String> filterParamArgIds, String id) {
return filterParamArgIds.contains(id);
}
And finally, as a reference MyRecord referred above can be defined something like this.
public class MyRecord implements Serializable {
#QuerySqlField(name = "city", index = true)
private String city;
#QuerySqlField(name = "flight", index = true)
private String flight;
}
I am trying to perform an insert with EF 6.
I have verified I have a connection to the database, because I can do a read:
List<Driver> drivers = DataContext.Drivers.ToList();
With a sql profiler, I can see this do a select on the database, and it returns an item I manually inserted.
I am trying to perform an insert like this:
var driver = new Driver();
driver.DriverName = "Blah";
DataContext.Drivers.Add(driver);
DataContext.ChangeTracker.HasChanges(); //false
DataContext.SaveChanges();
except nothing is inserted, and the changetracker seems to show that it has not detected any changes. I also saw suggestions to use .Attach but this had the same results.
Any help on what I am doing wrong?
Cheers
(MyEntities.Context.cs)
public partial class MyEntities : DbContext
{
public MyEntities()
: base("name=MyEntities")
{
}
public partial class MyDataContext : MyEntities
{
public class SqlDataService : DataServiceBase<...Data.MyDataContext>
{
//where I am trying to do the insert with the code above
edit: No not using code first (not that i'm aware of!) not sure if the above code samples help, but show how I have set up my classes
It seems you have AutomaticTrackChanges turned off somewhere in your code.
Try adding this line before the addition:
var driver = new Driver();
driver.DriverName = "Blah";
//Turning Automatic changes tracking on:
DataContext.Configuration.AutoDetectChangesEnabled = true;
DataContext.Drivers.Add(driver);
DataContext.ChangeTracker.HasChanges(); //True
DataContext.SaveChanges();
Note: AutoDetectChangesEnabled is usually turned off for performance considerations
I'm new to NHibernate and was assigned to a task where I have to change a value of an entity property and then compare if this new value (cached) is different from the actual value stored on the DB. However, every attempt to retrieve this value from the DB resulted in the cached value. As I said, I'm new to NHibernate, maybe this is something easy to do and obviously could be done with plain ADO.NET, but the client demands that we use NHibernate for every access to the DB. In order to make things clearer, those were my "successful" attempts (ie, no errors):
1
DetachedCriteria criteria = DetachedCriteria.For<User>()
.SetProjection(Projections.Distinct(Projections.Property(UserField.JobLoad)))
.Add(Expression.Eq(UserField.Id, userid));
return GetByDetachedCriteria(criteria)[0].Id; //this is the value I want
2
var JobLoadId = DetachedCriteria.For<User>()
.SetProjection(Projections.Distinct(Projections.Property(UserField.JobLoad)))
.Add(Expression.Eq(UserField.Id, userid));
ICriteria criteria = JobLoadId.GetExecutableCriteria(NHibernateSession);
var ids = criteria.List();
return ((JobLoad)ids[0]).Id;
Hope I made myself clear, sometimes is hard to explain a problem when even you don't quite understand the underlying framework.
Edit: Of course, this is a method body.
Edit 2: I found out that it doesn't work properly for the method call is inside a transaction context. If I remove the transaction, it works fine, but I need it to be in this context.
I do that opening a new stateless session for geting the actual object in the database:
User databaseuser;
using (IStatelessSession session = SessionFactory.OpenStatelessSession())
{
databaseuser = db.get<User>("id");
}
//do your checks
Within a session, NHibernate will return the same object from its Level-1 Cache (aka Identity Map). If you need to see the current value in the database, you can open a new session and load the object in that session.
I would do it like this:
public class MyObject : Entity
{
private readonly string myField;
public string MyProperty
{
get { return myField; }
set
{
if (value != myField)
{
myField = value;
DoWhateverYouNeedToDoWhenItIsChanged();
}
}
}
}
googles nhforge
http://nhibernate.info/doc/howto/various/finding-dirty-properties-in-nhibernate.html
This may be able to help you.
I am having a minor problem with WCF service proxies where the message contains List<string> as a parameter.
I am using the 'Add Service reference' in Visual Studio to generate a reference to my service.
// portion of my web service message
public List<SubscribeInfo> Subscribe { get; set; }
public List<string> Unsubscribe { get; set; }
These are the generated properties on my MsgIn for one of my web methods.
You can see it used ArrayOfString when I am using List<string>, and the other takes List<SubscribeInfo> - which matches my original C# object above.
[System.Runtime.Serialization.DataMemberAttribute(EmitDefaultValue=false)]
public System.Collections.Generic.List<DataAccess.MailingListWSReference.SubscribeInfo> Subscribe {
get {
return this.SubscribeField;
}
set {
if ((object.ReferenceEquals(this.SubscribeField, value) != true)) {
this.SubscribeField = value;
this.RaisePropertyChanged("Subscribe");
}
}
}
[System.Runtime.Serialization.DataMemberAttribute(EmitDefaultValue=false)]
publicDataAccess.MailingListWSReference.ArrayOfString Unsubscribe {
get {
return this.UnsubscribeField;
}
set {
if ((object.ReferenceEquals(this.UnsubscribeField, value) != true)) {
this.UnsubscribeField = value;
this.RaisePropertyChanged("Unsubscribe");
}
}
}
The ArrayOfString class generated looks like this. This is a class generated in my code - its not a .NET class. It actually generated me a class that inherits from List, but didn't have the 'decency' to create me any constructors.
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "3.0.0.0")]
[System.Runtime.Serialization.CollectionDataContractAttribute(Name="ArrayOfString", Namespace="http://www.example.com/", ItemName="string")]
[System.SerializableAttribute()]
public class ArrayOfString : System.Collections.Generic.List<string> {
}
The problem is that I often create my message like this :
client.UpdateMailingList(new UpdateMailingListMsgIn()
{
Email = model.Email,
Name = model.Name,
Source = Request.Url.ToString(),
Subscribe = subscribeTo.ToList(),
Unsubscribe = unsubscribeFrom.ToList()
});
I really like the clean look this gives me.
Now for the actual problem :
I cant assign a List<string> to the Unsubscribe property which is an ArrayOfString - even though it inherits from List. In fact I cant seem to find ANY way to assign it without extra statements.
I've tried the following :
new ArrayOfString(unsubscribeFrom.ToList()) - this constructor doesn't exist :-(
changing the type of the array used by the code generator - doesn't work - it always gives me ArrayOfString (!?)
try to cast List<string> to ArrayOfString - fails with 'unable to cast', even though it compiles just fine
create new ArrayOfString() and then AddRange(unsubscribeFrom.ToList()) - works, but I cant do it all in one statement
create a conversion function ToArrayOfString(List<string>), which works but isn't as clean as I want.
Its only doing this for string, which is annoying.
Am i missing something? Is there a way to tell it not to generate ArrayOfString - or some other trick to assign it ?
Any .NET object that implements a method named "Add" can be initialized just like arrays or dictionaries.
As ArrayOfString does implement an "Add" method, you can initialize it like this:
var a = new ArrayOfString { "string one", "string two" };
But, if you really want to initialize it based on another collection, you can write a extension method for that:
public static class U
{
public static T To<T>(this IEnumerable<string> strings)
where T : IList<string>, new()
{
var newList = new T();
foreach (var s in strings)
newList.Add(s);
return newList;
}
}
Usage:
client.UpdateMailingList(new UpdateMailingListMsgIn()
{
Email = model.Email,
Name = model.Name,
Source = Request.Url.ToString(),
Subscribe = subscribeTo.ToList(),
Unsubscribe = unsubscribeFrom.To<ArrayOfString>()
});
I prefer not to return generic types across a service boundary in the first place. Instead return Unsubscribe as a string[], and SubscriptionInfo as SubscriptionInfo[]. If necessary, an array can easily be converted to a generic list on the client, as follows:
Unsubscribe = new List<string>(unsubscribeFrom);
Subscribe = new List<SubscriptionInfo>(subscribeTo);
Too late but can help people in the future...
Use the svcutil and explicitly inform the command line util that you want the proxy class to be serialized by the XmlSerializer and not the DataContractSerializer (default). Here's the sample:
svcutil /out:c:\Path\Proxy.cs /config:c:\Path\Proxy.config /async /serializer:XmlSerializer /namespace:*,YourNamespace http://www.domain.com/service/serviceURL.asmx
Note that the web service is an ASP.NET web service ok?!
If you are using VS 2008 to consume service then there is an easy solution.
Click on the "Advanced..." button on the proxy dialog that is displayed when you add a Service Reference. In the Collection Type drop down you can select System.Generic.List. The methods returning List should now work properly.
(Hope this is what you were asking for, I'm a little tired and the question was a tad difficult for me to read.)