ModelContainers.md

Model Containers

Model Containers (ModelContainer) are mirrors to actual Model classes. Instead of parsing the data from a map, JSON object, or other form of data, converting the data into a Model and then saving it, we directly save it to the database using a Model blueprint. This eliminates a layer of processing and is much more efficient.

Please note that they come with these restrictions:

1. They must reference an existing Model table from the same database that you define.
2. You cannot SELECT from any ModelContainer class is it does not exist as a table. It implements Model as a convenience method to enable it to operate like a Model.
3. Make sure to reference the correct table as it will not know that it's the wrong table
4. This is NOT a fully featured JSON/Map/Object parser inside an ORM database library. It is limited and is useful for simple datasets.

Interesting features:

1. Can be Foreign key fields to enable lazy-loading of data such as ForeignKeyContainer.
2. Can define your own container via subclassing/implementing ModelContainer.
3. The column can have a @ContainerKey to specify a different key name from the ModelContainer than the column name.

Example

JSONModel<TestObject> jsonModel = new JSONModel<>(json, TestObject.class);

// constructs an insert or update query based on the JSON contents
jsonModel.save(false);

// deletes a model based on the JSON contents
jsonModel.delete(false);

Supported Kinds

MapModelContainer: takes a Map and operates it like a Model.

JSONModel````: usesJSONObject```

JSONArrayModel: all operations are on the contained JSONObject as one "Model". Each inner JSONObject is treated like a JSONModel.

ForeignKeyContainer: enables lazy-loading of foreign key fields. Instead of querying for the Model when a parent Model loads, we can choose when to load the foreign key object using toModel().