Repository (Deep Java Library 0.9.0 API specification)

All Known Implementing Classes:

AbstractRepository, JarRepository, LocalRepository, RemoteRepository, SimpleRepository, SimpleUrlRepository
```
public interface Repository
```
Repository is a format for storing data Artifacts for various uses including deep learning models and datasets.
This repository format is based off of the design of the Maven Repository format (See maven). Unlike in Maven, the data doesn't need to be located within the repository. Instead, the repository only stores metadata including the URL and checksum of the actual data. When the artifact is prepared, the data is downloaded, checked, and then stored in the ~/.djo-ai/cache folder.
The artifacts are first divided into a number of Metadata files that can each have multiple artifacts. The metadata files are identified by an MRL which contains:
- type - The resource type, e.g. model or dataset.
- Application - The resource application (See Application).
- Group Id - The group id identifies the group publishing the artifacts using a reverse domain name system.
- Artifact Id - The artifact id identifies the different artifacts published by a single group.
Within each metadata are a number of artifacts that share the same groupId, artifactId, name, description, website, and update date. The artifacts within the metadata differ primarily based on name and properties. Note that there is a metadata name and a separate artifact name. The properties are a map with string property names and string property values that can be used to represent key differentiators between artifacts such as dataset, flavors, and image sizes. For example, you might have a ResNet metadata file with different artifacts to represent different hyperparameters and datasets used for training the ResNet.
Each artifact contains a Version number (which can be a snapshot version). The data in the artifacts are represented by files in the format of an Artifact.Item and a parsed JSON object of arguments. The files can either by a single file, an automatically extracted gzip file, or an automatically extracted zip file that will be treated as a directory. These can be used to store data such as the dataset, model parameters, and synset files. The arguments can be used to store data about the model used for initialization. For example, it can store the image size which can be used by the model loader for both initializing the block and setting up resizing in the translator.
There are three kinds of repositories: a LocalRepository, RemoteRepository, and SimpleRepository. For all three kinds, new repositories should be created by calling newInstance(String, String) with the location of the repository.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`java.net.URI`	`getBaseUri()` Returns the URI to the base of the repository.
`java.nio.file.Path`	`getCacheDirectory()` Returns the cache directory for the repository.
`java.nio.file.Path`	`getFile(Artifact.Item item, java.lang.String path)` Returns the path to a file for the item.
`java.lang.String`	`getName()` Returns the repository name.
`default java.nio.file.Path`	`getResourceDirectory(Artifact artifact)` Returns the resource directory for the an artifact.
`java.util.List<MRL>`	`getResources()` Returns a list of `MRL`s in the repository.
`boolean`	`isRemote()` Returns whether the repository is remote repository.
`java.lang.String[]`	`listDirectory(Artifact.Item item, java.lang.String path)` Returns the list of files directly within a specified directory in a zipped directory item.
`Metadata`	`locate(MRL mrl)` Returns the metadata at a mrl.
`static Repository`	`newInstance(java.lang.String name, java.nio.file.Path path)` Creates a new instance of a repository with a name and url.
`static Repository`	`newInstance(java.lang.String name, java.lang.String url)` Creates a new instance of a repository with a name and url.
`java.io.InputStream`	`openStream(Artifact.Item item, java.lang.String path)` Returns an `InputStream` for an item in a repository.
`default void`	`prepare(Artifact artifact)` Prepares the artifact for use.
`void`	`prepare(Artifact artifact, ai.djl.util.Progress progress)` Prepares the artifact for use with progress tracking.
`static void`	`registerRepositoryFactory(RepositoryFactory factory)` Registers a `RepositoryFactory` to handle the specified url scheme.
`Artifact`	`resolve(MRL mrl, java.lang.String version, java.util.Map<java.lang.String,java.lang.String> filter)` Returns the artifact matching a mrl, version, and property filter.

- Method Detail
  - newInstance
```
static Repository newInstance(java.lang.String name,
                              java.nio.file.Path path)
```
    Creates a new instance of a repository with a name and url.
    
    Parameters:
    
    name - the repository name
    
    path - the repository location
    
    Returns:
    
    the new repository
  - newInstance
```
static Repository newInstance(java.lang.String name,
                              java.lang.String url)
```
    Creates a new instance of a repository with a name and url.
    
    Parameters:
    
    name - the repository name
    
    url - the repository location
    
    Returns:
    
    the new repository
  - registerRepositoryFactory
```
static void registerRepositoryFactory(RepositoryFactory factory)
```
    Registers a RepositoryFactory to handle the specified url scheme.
    
    Parameters:
    
    factory - the RepositoryFactory to be registered
  - isRemote
```
boolean isRemote()
```
    Returns whether the repository is remote repository.
    
    Returns:
    
    whether the repository is remote repository
  - getName
```
java.lang.String getName()
```
    Returns the repository name.
    
    Returns:
    
    the repository name
  - getBaseUri
```
java.net.URI getBaseUri()
```
    Returns the URI to the base of the repository.
    
    Returns:
    
    the URI
  - locate
```
Metadata locate(MRL mrl)
         throws java.io.IOException
```
    Returns the metadata at a mrl.
    
    Parameters:
    
    mrl - the mrl of the metadata to retrieve
    
    Returns:
    
    the metadata
    
    Throws:
    
    java.io.IOException - if it failed to load the metadata
  - resolve
```
Artifact resolve(MRL mrl,
                 java.lang.String version,
                 java.util.Map<java.lang.String,java.lang.String> filter)
          throws java.io.IOException
```
    Returns the artifact matching a mrl, version, and property filter.
    
    Parameters:
    
    mrl - the mrl to match the artifact against
    
    version - the version of the artifact
    
    filter - the property filter
    
    Returns:
    
    the matched artifact
    
    Throws:
    
    java.io.IOException - if it failed to load the artifact
  - openStream
```
java.io.InputStream openStream(Artifact.Item item,
                               java.lang.String path)
                        throws java.io.IOException
```
    Returns an InputStream for an item in a repository.
    
    Parameters:
    
    item - the item to open
    
    path - the path to a file if the item is a zipped directory. Otherwise, pass null
    
    Returns:
    
    the file stream
    
    Throws:
    
    java.io.IOException - if it failed to open the stream
  - getFile
```
java.nio.file.Path getFile(Artifact.Item item,
                           java.lang.String path)
                    throws java.io.IOException
```
    Returns the path to a file for the item.
    
    Parameters:
    
    item - the item to find the path for
    
    path - the path to a file if the item is a zipped directory. Otherwise, pass null
    
    Returns:
    
    the file path
    
    Throws:
    
    java.io.IOException - if it failed to find the path
  - listDirectory
```
java.lang.String[] listDirectory(Artifact.Item item,
                                 java.lang.String path)
                          throws java.io.IOException
```
    Returns the list of files directly within a specified directory in a zipped directory item.
    
    Parameters:
    
    item - the zipped directory item
    
    path - the path within the zip directory
    
    Returns:
    
    the list of files/directories
    
    Throws:
    
    java.io.IOException - if it failed to list the directory
  - prepare
```
default void prepare(Artifact artifact)
              throws java.io.IOException
```
    Prepares the artifact for use.
    
    Parameters:
    
    artifact - the artifact to prepare
    
    Throws:
    
    java.io.IOException - if it failed to prepare
  - prepare
```
void prepare(Artifact artifact,
             ai.djl.util.Progress progress)
      throws java.io.IOException
```
    Prepares the artifact for use with progress tracking.
    
    Parameters:
    
    artifact - the artifact to prepare
    
    progress - the progress tracker
    
    Throws:
    
    java.io.IOException - if it failed to prepare
  - getCacheDirectory
```
java.nio.file.Path getCacheDirectory()
                              throws java.io.IOException
```
    Returns the cache directory for the repository.
    
    Returns:
    
    the cache directory path
    
    Throws:
    
    java.io.IOException - if it failed to ensure the creation of the cache directory
  - getResourceDirectory
```
default java.nio.file.Path getResourceDirectory(Artifact artifact)
                                         throws java.io.IOException
```
    Returns the resource directory for the an artifact.
    
    Parameters:
    
    artifact - the artifact whose resource directory to return
    
    Returns:
    
    the resource directory path
    
    Throws:
    
    java.io.IOException - if it failed to ensure the creation of the cache directory
  - getResources
```
java.util.List<MRL> getResources()
```
    Returns a list of MRLs in the repository.
    An empty list will be returned if underlying Repository implementation does not support this feature.
    
    Returns:
    
    a list of MRLs in the repository

Interface Repository

Method Summary

Method Detail

newInstance

newInstance

registerRepositoryFactory

isRemote

getName

getBaseUri

locate

resolve

openStream

getFile

listDirectory

prepare

prepare

getCacheDirectory

getResourceDirectory

getResources