org.openimaj.data.dataset

Class VFSGroupDataset<INSTANCE>

java.lang.Object

java.util.AbstractMap<KEY,DATASET>

org.openimaj.data.dataset.ReadableGroupDataset<String,VFSListDataset<INSTANCE>,INSTANCE,org.apache.commons.vfs2.FileObject>

org.openimaj.data.dataset.VFSGroupDataset<INSTANCE>

Type Parameters:

INSTANCE - The type of instance in the dataset

All Implemented Interfaces:

Iterable<INSTANCE>, Map<String,VFSListDataset<INSTANCE>>, Dataset<INSTANCE>, GroupedDataset<String,VFSListDataset<INSTANCE>,INSTANCE>, Identifiable

public class VFSGroupDataset<INSTANCE>
extends ReadableGroupDataset<String,VFSListDataset<INSTANCE>,INSTANCE,org.apache.commons.vfs2.FileObject>
implements Identifiable

A GroupedDataset of VFSListDatasets backed by directories of items (either locally or remotely), or items stored in a hierarchical structure within a compressed archive.

This implementation only supports a basic grouped dataset with String keys created from the names of directories, and VFSListDataset values from all the readable files within each directory.

As an example, this class can be used to easily create a GroupedDataset from a directory containing directories of images:

 GroupedDataset<String, VFSListDataset<FImage>, FImage> dataset = new VFSGroupDataset<FImage>(
                "/path/to/directory/of/images",
                ImageUtilities.FIMAGE_READER);
 

a zip file of directories of images:

 GroupedDataset<String, VFSListDataset<FImage>, FImage> dataset = new VFSGroupDataset<FImage>(
                "zip:file:/path/to/images.zip", ImageUtilities.FIMAGE_READER);
 

or even a remote zip of directories of images hosted via http:

 GroupedDataset<String, VFSListDataset<FImage>, FImage> dataset = new VFSGroupDataset<FImage>(
                "zip:http://localhost/˜jsh2/thumbnails.zip", ImageUtilities.FIMAGE_READER);
 

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Field Summary

Fields inherited from class org.openimaj.data.dataset.ReadableGroupDataset

reader

Constructor Summary

Constructors

Constructor and Description
VFSGroupDataset(String path, InputStreamObjectReader<INSTANCE> reader) Construct a grouped dataset from any virtual file system source (local directory, remote zip file, etc).
VFSGroupDataset(String path, ObjectReader<INSTANCE,org.apache.commons.vfs2.FileObject> reader) Construct a grouped dataset from any virtual file system source (local directory, remote zip file, etc).

Method Summary

Modifier and Type	Method and Description
Set<Map.Entry<String,VFSListDataset<INSTANCE>>>	entrySet()
org.apache.commons.vfs2.FileObject	getFileObject(String key) Get the underlying file descriptor for a particular group in the dataset.
Map<String,org.apache.commons.vfs2.FileObject>	getGroupDirectories() Get the underlying file descriptors of the directories that form the groups of the dataset
String	getID()
String	toString()

Methods inherited from class org.openimaj.data.dataset.ReadableGroupDataset

getGroups, getInstances, getRandomInstance, getRandomInstance, iterator, numInstances

Methods inherited from class java.util.AbstractMap

clear, clone, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.openimaj.data.identity.Identifiable

equals

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface java.util.Map

clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Constructor Detail

VFSGroupDataset

public VFSGroupDataset(String path,
                       InputStreamObjectReader<INSTANCE> reader)
                throws org.apache.commons.vfs2.FileSystemException

Construct a grouped dataset from any virtual file system source (local directory, remote zip file, etc). Only the child directories under the given path will be used to create groups; the contents of any sub-directories will be merged automatically. Only directories with readable items as children will be included in the resultant dataset.

Parameters:

path - the file system path or uri. See the Apache Commons VFS2 documentation for all the details.

reader - the InputStreamObjectReader that reads the data from the VFS

Throws:

org.apache.commons.vfs2.FileSystemException - if an error occurs accessing the VFS

See Also:

"http://commons.apache.org/proper/commons-vfs/filesystems.html"

VFSGroupDataset

public VFSGroupDataset(String path,
                       ObjectReader<INSTANCE,org.apache.commons.vfs2.FileObject> reader)
                throws org.apache.commons.vfs2.FileSystemException

Construct a grouped dataset from any virtual file system source (local directory, remote zip file, etc). Only the child directories under the given path will be used to create groups; the contents of any sub-directories will be merged automatically. Only directories with readable items as children will be included in the resultant dataset.

Parameters:

path - the file system path or uri. See the Apache Commons VFS2 documentation for all the details.

reader - the InputStreamObjectReader that reads the data from the VFS

Throws:

org.apache.commons.vfs2.FileSystemException - if an error occurs accessing the VFS

See Also:

"http://commons.apache.org/proper/commons-vfs/filesystems.html"

Method Detail

getGroupDirectories

public Map<String,org.apache.commons.vfs2.FileObject> getGroupDirectories()

Get the underlying file descriptors of the directories that form the groups of the dataset

Returns:

the array of file objects

getFileObject

public org.apache.commons.vfs2.FileObject getFileObject(String key)

Get the underlying file descriptor for a particular group in the dataset.

Parameters:

key - key of the group

Returns:

the file object corresponding to the instance

toString

public String toString()

Overrides:

toString in class AbstractMap<String,VFSListDataset<INSTANCE>>

entrySet

public Set<Map.Entry<String,VFSListDataset<INSTANCE>>> entrySet()

Specified by:

entrySet in interface Map<String,VFSListDataset<INSTANCE>>

Specified by:

entrySet in class AbstractMap<String,VFSListDataset<INSTANCE>>

getID

public String getID()

Specified by:

getID in interface Identifiable

Returns:

the identifier of this object