Core API - 4.2

This section describes key classes which are essential while using Slice. They constitute a base for a day-to-day development.

ModelProvider

The com.cognifide.slice.api.provider.ModelProvider interface is a base interface in Slice. It allows you to fetch an injectable object(s) mapped from specified resource or path. It's very similar to Guice com.google.inject.Injector because it is used for fetching objects of different classes. However it's more Sling-related because it always takes resource (or path) as a parameter, so that an object of the specified class can be mapped. You should use ModelProvider whenever there is a need for injecting a model mapped from a given resource (path).

ModelProvider allows you to fetch either a single object of a specified class or a list of objects of a specified class. During execution of methods of this interface, the execution context is modified, meaning that the specified path is put on the top of the execution stack. This allows other objects to inject the specified resource (or path) and use it as a current resource. Read more about execution stack here.

Below table describes methods of the interface.

Method	Description
`<T> T get(Class<T> type, String path);`	Creates an object of class type and maps it from a resource from under specified path
`<T> T get(Class<T> type, Resource resource);`	Creates an object of class type and maps it from the resource
`<T> T get(com.google.inject.Key<T> key, String path) throws ClassNotFoundException;`	Creates an object identified by key type and maps it from the resource under specified path
`<T> T get(com.google.inject.Key<T> key, Resource resource);`	Creates an object identified by key type and maps it from the resource under specified path
`<T> List<T> getChildModels(Class<T> type, String parentPath);`	Creates a list of objects of class type and maps it from the resources under specified parent path
`<T> List<T> getChildModels(Class<T> type, Resource parentResource);`	Creates a list of objects of class type and maps it from the resources under specified parent resource
`Object get(String className, String path) throws ClassNotFoundException;`	Creates an object of a class defined by specified className String and maps it from a resource from under specified path
`Object get(String className, Resource resource) throws ClassNotFoundException;`	Creates an object of a class defined by specified className String and maps it from the resource
`<T> List<T> getList(Class<T> type, Iterator<String> paths);`	Creates a list of objects of class type and maps them accordingly from resources from under paths defined by paths iterator.
`<T> List<T> getList(Class<T> type, String[] paths);`	Creates a list of objects of class type and maps them accordingly from resources from under paths defined by paths array.
`<T> List<T> getListFromResources(Class<T> type, Iterator<Resource> resources);`	Creates a list of objects of class type and maps it from corresponding resources returned by iterator

ModelProvider can be injected to your models, so that you can read a model from an arbitrary resource or path, e.g.:

import com.cognifide.app.util.Currency;

import com.cognifide.slice.api.provider.ModelProvider;
import com.cognifide.slice.mapper.annotation.JcrProperty;
import com.cognifide.slice.mapper.annotation.SliceResource;
import com.google.inject.Inject;

@SliceResource
public class OrderModel {

    private final static String CONFIGURATION_PATH = "/content/app/configuration/jcr:content/currency";

    private final ModelProvider modelProvider;

    @JcrProperty
    private int value;

    @Inject
    public OrderModel(ModelProvider modelProvider) {
        this.modelProvider = modelProvider;
    }

    public int getValue() {
        Currency currency = modelProvider.get(Currency.class, CONFIGURATION_PATH);
        return formatToCurrency(value, currency);
    }
    ...
}

`@Deprecated API`

Few API members have been deprecated in Slice 4.0 and should be avoided where possible.

Deprecated Suggestion

com.cognifide.slice.api.provider.ChildrenProvider

Use one of ModelProvider's methods:

<T> List<T> getChildModels(Class<T> type, String parentPath);
<T> List<T> getChildModels(Class<T> type, Resource parentResource);
<T> List<T> getList(Class<T> type, String[] paths);
<T> List<T> getList(Class<T> type, Iterator<String> paths);

com.cognifide.slice.api.provider.ModelProvider

getChildren(String path)
getChildResources(String path)

Use Resource.listChildren()

com.cognifide.slice.api.link.*

Whole package (link API) has been removed in Slice 4.0.0

If your code is dependent on it, feel free to extract code from Slice 3.2.0 source code: https://github.com/Cognifide/Slice/tree/3.2.0

ClassToKeyMapper

The com.cognifide.slice.api.provider.ClassToKeyMapper is no longer part of the Slice API - it has been moved to com.cognifide.slice.core.internal.provider.ClassToKeyMapper