MongoDbPersistence

_dependencyResolver

The dependency resolver.

protected DependencyResolver _dependencyResolver = new DependencyResolver(_defaultConfig);

_logger

The logger.

protected CompositeLogger _logger = new CompositeLogger;

_connection

The MongoDB connection component.

protected MongoDBConnection _connection;

_collectionName

The MongoDB colleciton name.

protected String _collectionName;

_collection

The MongoDb collection object.

protected MongoCollection _collection;

_client

The MongoDB connection pool object.

protected MongoClient _client;

_databaseName

The MongoDB database name.

protected _databaseName: string

_db

The MongoDb database object.

protected MongoDatabase _db;

_maxPageSize

The maximum number of records to return from the database per request.

protected long _maxPageSize = 100;

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Instance methods

clear

Clears a component’s state.

public void clear(IContext context) throws ApplicationException

• context: IContext - a context to trace execution through a call chain.

clearSchema

Clears all auto-created objects

protected void clearSchema()

close

Closes the component and frees used resources.

public void close(IContext context) throws ApplicationException

• context: IContext - a context to trace execution through a call chain.

configure

Closes the component and frees used resources.

public void configure(ConfigParams config) throws ConfigException

• config: ConfigParams - configuration parameters to be set.

convertFromPublic

Converts an object value from public to internal format.

protected Document convertFromPublic(Object value)

• value: Object - object in public format to convert.
• returns: Document - converted object in internal format.

convertToPublic

Converts and object value from internal to public format.

protected T convertToPublic(Document value)

• value: Document - object in internal format to convert.
• returns: T - converted object in public format.

create

Creates a data item.

public T create(IContext context, T item)

• context: IContext - (optional) a context to trace execution through a call chain.
• item: T - item to be created.
• returns: T - created item

defineSchema

Defines the database schema

protected void defineSchema()

deleteByFilter

This method shall be called by a public deleteByFilter method from the child class that receives FilterParams and converts them into a filter function.

public void deleteByFilter(IContext context, Bson filter)

• context: IContext - (optional) a context to trace execution through a call chain.
• filter: Bson - (optional) filter function used to filter items.

ensureIndex

Adds index definition to create it on opening.

protected void ensureIndex(Bson keys, IndexOptions options)

• keys: Bson - index keys (fields)
• options: IndexOptions - index options

getCountByFilter

Gets a number of data items retrieved by a given filter.

This method shall be called by a public getCountByFilter method from the child class that receives FilterParams and converts them into a filter function.

protected Long getCountByFilter(IContext context, Bson filter)

• context: IContext - (optional) a context to trace execution through a call chain.
• filter: Bson - (optional) filter JSON object
• returns: Long - number of filtered items.

getListByFilter

Gets a list of data items retrieved by a given filter and sorted according to sort parameters.

This method shall be called by a public getListByFilter method from the child class that receives FilterParams and converts them into a filter function.

protected List getListByFilter(IContext context, Bson filter, Bson sort, Bson select)

• context: IContext - (optional) a context to trace execution through a call chain.
• filter: Bson - (optional) filter function used to filter items
• sort: Bson - (optional) sorting parameters
• select: Bson - (optional) projection parameters (not used yet)
• returns: List - data list of results by filter.

getOneRandom

Gets a random item from items that match to a given filter.

This method shall be called by a public getOneRandom method from the child class that receives FilterParams and converts them into a filter function.

protected T getOneRandom(IContext context, Bson filter)

• context: IContext - (optional) a context to trace execution through a call chain.
• filter: Bson - fileter JSON object.
• returns: T - random item.

getPageByFilter

Gets a page of data items retrieved by a given filter and sorted according to sort parameters.

This method shall be called by a public getPageByFilter method from the child class that receives FilterParams and converts them into a filter function.

protected DataPage getPageByFilter(IContext context, Bson filter, PagingParams paging, Bson sort, Bson select)

• context: IContext - (optional) a context to trace execution through a call chain.
• filter: Bson - (optional) filter JSON object
• paging: PagingParams - (optional) paging parameters
• sort: Bson - (optional) sorting JSON object
• select: Bson - (optional) projection JSON object
• returns: DataPage - data page obtained by filtering

Examples

{@code
class MyMongoDbPersistence extends MongoDbPersistence<MyData> {

  public MyMongoDbPersistence() {
      super("mydata", MyData.class);
  }

  public MyData getByName(IContext context, String name) {
  	Bson filter = Filters.eq("name", name);
  	MyData item = _collection.find(filter).first();
  	return item;
  }

  public MyData set(IContext context, MyData item) {
      Bson filter = Filters.eq("name", item.getName());

      FindOneAndReplaceOptions options = new FindOneAndReplaceOptions();
      options.returnDocument(ReturnDocument.AFTER);
      options.upsert(true);

      MyData result = _collection.findOneAndReplace(filter, item, options);
      return result;
  }

}

MyMongoDbPersistence persistence = new MyMongoDbPersistence();
persistence.configure(ConfigParams.fromTuples(
    "host", "localhost",
    "port", 27017
));

persitence.open("123");
MyData mydata = new MyData("ABC");
persistence.set("123", mydata);
persistence.getByName("123", "ABC");
System.out.println(item);                   // Result: { name: "ABC" }
}