haberman.rhizomatics.data

Class DataManager

java.lang.Object

android.database.sqlite.SQLiteOpenHelper

haberman.rhizomatics.data.DataManager

public class DataManager
extends android.database.sqlite.SQLiteOpenHelper

This class extends SQLiteOpenHelper and allows data-driven map features creation. It acts as a intermediate between a live data API (currently hard-coded under R.raw.) and the end-user interactions.

Field Summary

Fields

Modifier and Type	Field and Description
private android.content.Context	context_ Application's context background.
private static java.lang.String	DATABASE_NAME
private static int	DATABASE_VERSION Database constants
private android.database.sqlite.SQLiteDatabase[]	dbs_ Readable & writable persistent databases' connections.
private static int	JSON_BACKEND
private static java.lang.String	PLACE_AUTHOR
private static java.lang.String[]	PLACE_COLUMNS
private static java.lang.String	PLACE_ID Places tables's fields.
private static java.lang.String	PLACE_NAME
private static java.lang.String	PLACE_SHAPE
private static java.lang.String	PLACE_TABLE
private static java.lang.String	PLACE_THEME
private static java.lang.String[]	PLACE_TYPES
private java.util.ArrayList<PlaceEntity>	places_ Keeps an in-memory tracks of all places.
private static java.lang.String[]	SOUND_COLUMNS
private static java.lang.String	SOUND_ID Sounds tables's fields.
private static java.lang.String	SOUND_PLACE
private static java.lang.String	SOUND_TABLE
private static java.lang.String	SOUND_TRACK
private static java.lang.String[]	SOUND_TYPES
private static java.lang.String	SOUND_WHERE

Constructor Summary

Constructors

Constructor and Description
DataManager(android.content.Context context) Constructor.

Method Summary

Modifier and Type	Method and Description
java.util.ArrayList<PlaceEntity>	all_places() Fetches all places stored in the PLACE_TABLE table.
java.util.ArrayList<SoundEntity>	all_sounds(java.lang.String place_id) Gets all sounds belonging to a specific PlaceEntity.
void	close() Closes the connection on both readable and writable databases.
private int	count_places() Returns the total amount of places.
private java.lang.String	create_table_query(java.lang.String table, java.lang.String[] columns, java.lang.String[] types) Utility function to generate a `CREATE TABLE` query where every column is of type `TEXT`, the first one being a primary key.
private void	drop(android.database.sqlite.SQLiteDatabase db) Deletes table and recreates.
Area	init() Checks that we have actual data it the database; fills it with the (currently hard-coded) JSON_BACKEND.
private void	insert_place(org.json.JSONObject place) Mapping function that takes care of JSON -> `place` SQLITE injection.
private void	insert_sound(java.lang.String place_id, org.json.JSONObject sound) Mapping function that takes care of JSON -> `sound` SQLITE injection.
SoundEntity	inside_sound(java.lang.String place_id) Returns all sounds of "inside" type.
static float	min_distance_place(com.mapbox.mapboxsdk.geometry.LatLng reference, java.util.ArrayList<PlaceEntity> places) Returns the minimum distance between a reference point and a list of PlaceEntitys.
static java.util.ArrayList<PlaceEntity>	nearest_place_list(com.mapbox.mapboxsdk.geometry.LatLng reference, java.util.ArrayList<PlaceEntity> places, short amount) Returns a given amount list of PlaceEntitys being the nearest of a given reference.
private static PlaceEntity	nearest_place(com.mapbox.mapboxsdk.geometry.LatLng reference, java.util.ArrayList<PlaceEntity> places) Given a list of locations, returns the nearest geographical coordinates of a reference point.
void	onCreate(android.database.sqlite.SQLiteDatabase db) Creates table structure after database creation.
void	onDowngrade(android.database.sqlite.SQLiteDatabase db, int oldVersion, int newVersion) Called on database version downgrade.
void	onUpgrade(android.database.sqlite.SQLiteDatabase db, int oldVersion, int newVersion) Called on database version upgrade.
static java.util.ArrayList<PlaceEntity>	remove_farthest_place(PlaceEntity reference, java.util.ArrayList<PlaceEntity> places) Given a list of PlaceEntitys and a reference point, returns the same list without its farthest location.

Methods inherited from class android.database.sqlite.SQLiteOpenHelper

getDatabaseName, getReadableDatabase, getWritableDatabase, onConfigure, onOpen, setWriteAheadLoggingEnabled

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JSON_BACKEND

@RawRes
private static final int JSON_BACKEND

See Also:

Constant Field Values

DATABASE_VERSION

private static final int DATABASE_VERSION

Database constants

See Also:

Constant Field Values

DATABASE_NAME

private static final java.lang.String DATABASE_NAME

See Also:

Constant Field Values

PLACE_ID

private static final java.lang.String PLACE_ID

Places tables's fields.

See Also:

Constant Field Values

PLACE_NAME

private static final java.lang.String PLACE_NAME

See Also:

Constant Field Values

PLACE_AUTHOR

private static final java.lang.String PLACE_AUTHOR

See Also:

Constant Field Values

PLACE_THEME

private static final java.lang.String PLACE_THEME

See Also:

Constant Field Values

PLACE_SHAPE

private static final java.lang.String PLACE_SHAPE

See Also:

Constant Field Values

PLACE_TABLE

private static final java.lang.String PLACE_TABLE

See Also:

Constant Field Values

PLACE_COLUMNS

private static final java.lang.String[] PLACE_COLUMNS

PLACE_TYPES

private static final java.lang.String[] PLACE_TYPES

SOUND_ID

private static final java.lang.String SOUND_ID

Sounds tables's fields.

See Also:

Constant Field Values

SOUND_TRACK

private static final java.lang.String SOUND_TRACK

See Also:

Constant Field Values

SOUND_WHERE

private static final java.lang.String SOUND_WHERE

See Also:

Constant Field Values

SOUND_PLACE

private static final java.lang.String SOUND_PLACE

See Also:

Constant Field Values

SOUND_TABLE

private static final java.lang.String SOUND_TABLE

See Also:

Constant Field Values

SOUND_COLUMNS

private static final java.lang.String[] SOUND_COLUMNS

SOUND_TYPES

private static final java.lang.String[] SOUND_TYPES

context_

private final android.content.Context context_

Application's context background.

dbs_

private final android.database.sqlite.SQLiteDatabase[] dbs_

Readable & writable persistent databases' connections.

places_

@Nullable
private java.util.ArrayList<PlaceEntity> places_

Keeps an in-memory tracks of all places.

Constructor Detail

DataManager

public DataManager(@NonNull
                   android.content.Context context)

Constructor. Creates a new child instance of SQLiteOpenHelper and a SoundPool.

Parameters:

context - The base Context of this app.

Method Detail

remove_farthest_place

public static java.util.ArrayList<PlaceEntity> remove_farthest_place(PlaceEntity reference,
                                                                     java.util.ArrayList<PlaceEntity> places)

Given a list of PlaceEntitys and a reference point, returns the same list without its farthest location.

Parameters:

reference - The LatLng reference's point

places - A list of LatLng to compare

Returns:

The filtered list.

min_distance_place

public static float min_distance_place(com.mapbox.mapboxsdk.geometry.LatLng reference,
                                       java.util.ArrayList<PlaceEntity> places)

Returns the minimum distance between a reference point and a list of PlaceEntitys.

Parameters:

reference - The reference point to measure the distance from

places - A list of PlaceEntity

Returns:

The maximum distance in meters.

nearest_place_list

public static java.util.ArrayList<PlaceEntity> nearest_place_list(@NonNull
                                                                  com.mapbox.mapboxsdk.geometry.LatLng reference,
                                                                  @NonNull
                                                                  java.util.ArrayList<PlaceEntity> places,
                                                                  short amount)

Returns a given amount list of PlaceEntitys being the nearest of a given reference.

Parameters:

reference - The location of the reference point

places - A list of PlaceEntity to compare

amount - The amount of locations to retrieve

Returns:

The list of the closest locations found.

nearest_place

@Nullable
private static PlaceEntity nearest_place(com.mapbox.mapboxsdk.geometry.LatLng reference,
                                                   java.util.ArrayList<PlaceEntity> places)

Given a list of locations, returns the nearest geographical coordinates of a reference point.

Parameters:

reference - The location of the reference point

places - A list of LatLng to compare

Returns:

The nearest location in the list or null if places is empty.

init

public final Area init()
                throws org.json.JSONException

Checks that we have actual data it the database; fills it with the (currently hard-coded) JSON_BACKEND.

Returns:

The root Area.

Throws:

org.json.JSONException - in case of badly written JSON.

count_places

private int count_places()

Returns the total amount of places.

Returns:

The number of places or -1 if there is no result.

insert_place

private void insert_place(org.json.JSONObject place)

Mapping function that takes care of JSON -> `place` SQLITE injection.

Parameters:

place - The JSONObject to map

insert_sound

private void insert_sound(java.lang.String place_id,
                          org.json.JSONObject sound)

Mapping function that takes care of JSON -> `sound` SQLITE injection.

Parameters:

place_id - The id of the place this sound belongs to

sound - The JSONObject to map

close

public void close()

Closes the connection on both readable and writable databases.

Overrides:

close in class android.database.sqlite.SQLiteOpenHelper

See Also:

dbs_

onCreate

public void onCreate(android.database.sqlite.SQLiteDatabase db)

Creates table structure after database creation.

Specified by:

onCreate in class android.database.sqlite.SQLiteOpenHelper

Parameters:

db - The database

onUpgrade

public void onUpgrade(android.database.sqlite.SQLiteDatabase db,
                      int oldVersion,
                      int newVersion)

Called on database version upgrade.

Specified by:

onUpgrade in class android.database.sqlite.SQLiteOpenHelper

Parameters:

db - The database

oldVersion - The old database version

newVersion - The new database version

See Also:

DATABASE_VERSION

onDowngrade

public void onDowngrade(android.database.sqlite.SQLiteDatabase db,
                        int oldVersion,
                        int newVersion)

Called on database version downgrade.

Overrides:

onDowngrade in class android.database.sqlite.SQLiteOpenHelper

Parameters:

db - The database

oldVersion - The old database version

newVersion - The new database version

See Also:

DATABASE_VERSION

drop

private void drop(android.database.sqlite.SQLiteDatabase db)

Deletes table and recreates.

Parameters:

db - A writable SQLite database

create_table_query

private java.lang.String create_table_query(java.lang.String table,
                                            java.lang.String[] columns,
                                            java.lang.String[] types)

Utility function to generate a `CREATE TABLE` query where every column is of type `TEXT`, the first one being a primary key.

Parameters:

table - The table name

columns - A list of columns that describes the table

types - The corresponding sql types of columns

Returns:

The sql query.

all_places

@Nullable
public java.util.ArrayList<PlaceEntity> all_places()

Fetches all places stored in the PLACE_TABLE table. The result of a first retrieval is cached inside places_.

Returns:

An array of PlaceEntity or null if there is no result.

all_sounds

@Nullable
public java.util.ArrayList<SoundEntity> all_sounds(java.lang.String place_id)

Gets all sounds belonging to a specific PlaceEntity.

Parameters:

place_id - The id of the place

Returns:

An array of SoundEntity or null if there is no result.

inside_sound

@Nullable
public final SoundEntity inside_sound(@NonNull
                                                java.lang.String place_id)

Returns all sounds of "inside" type.

Parameters:

place_id - The place from where we're searching inside sounds

Returns:

A SoundEntity or null if there is no result.