com.yoti.mobile.android.commons.util

Class SharedPreferencesBase

java.lang.Object

com.yoti.mobile.android.commons.util.SharedPreferencesBase

Direct Known Subclasses:

DeprecatedSharedPreferencesBase

public abstract class SharedPreferencesBase
extends java.lang.Object

Provides enhanced usability for persisting data to the default shared preferences file. Only use this implementation of the SharedPreferences if you are implementing a brand new SharedPreferences class. If you are trying to use a legacy one that requires migration from using non prefixed keys to prefixed keys rather use DeprecatedSharedPreferencesBase.

As SharedPreferences is just a basic key-value store, subclasses are expected to specify the prefix to be applied to the key to ensure that they are not inadvertently conflicting with other keys.

Subclasses must implement the following methods:

• getVersion()
• updateStoreData(int)

getVersion() must return the implementation version. This is the version that the SharedPreferences should be. If there is a breaking change to the information that is stored then this version should be incremented.

updateStoreData(int) must be implemented to perform the necessary updates of the data. This method will be called for every version between the currently stored version and the new implementation version returned by getVersion().

As of version 0.2.1 the keyPrefix is mandatory.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	DEFAULT_VERSION
protected android.content.Context	mContext
protected java.lang.String	mKeyPrefix
static java.lang.String	PREF_FILE

Constructor Summary

Constructors

Constructor and Description
SharedPreferencesBase(android.content.Context context, java.lang.String keyPrefix) Initialises a new instance of the SharedPreferencesBase.

Method Summary

Modifier and Type	Method and Description
protected java.lang.String	buildCompleteKey(java.lang.String key)
protected boolean	contains(java.lang.String key)
protected boolean	getBooleanPreference(java.lang.String key, boolean defaultValue)
protected int	getIntPreference(java.lang.String key, int defaultValue)
protected long	getLongPreference(java.lang.String key, long defaultValue)
protected android.content.SharedPreferences.Editor	getSharedEditor()
protected android.content.SharedPreferences	getSharedPreferences()
protected java.lang.String	getSharedPreferencesName() Gets the name of the class purely for logging purposes.
protected int	getStoredVersion() Get the currently stored version of the SharedPreferences implementation.
protected java.lang.String	getStringPreference(java.lang.String key, java.lang.String defaultValue)
protected java.util.Set<java.lang.String>	getStringSetPreference(java.lang.String key, java.util.Set<java.lang.String> defaultValues)
protected abstract int	getVersion() Gets the current version of the SharedPreferences implementation.
protected void	onPreCheckVersion() A hook to allow for subclasses to perform any tasks before the version is checked and any upgrades are done.
protected void	removePreference(java.lang.String key)
protected void	setBooleanPreference(java.lang.String key, boolean value)
protected void	setIntPreference(java.lang.String key, int value)
protected void	setLongPreference(java.lang.String key, long value)
protected void	setStoredVersion(int newVersion) Sets the version of the SharedPreferences.
protected void	setStringPreference(java.lang.String key, java.lang.String value)
protected void	setStringSetPreference(java.lang.String key, java.util.Set<java.lang.String> values)
protected abstract void	updateStoreData(int newVersion) Updates the SharedPreferences implementation to the new version.

Methods inherited from class java.lang.Object

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

Field Detail

PREF_FILE

public static final java.lang.String PREF_FILE

See Also:

Constant Field Values

DEFAULT_VERSION

protected static final int DEFAULT_VERSION

See Also:

Constant Field Values

mContext

protected final android.content.Context mContext

mKeyPrefix

protected final java.lang.String mKeyPrefix

Constructor Detail

SharedPreferencesBase

public SharedPreferencesBase(@NonNull
                             android.content.Context context,
                             @NonNull
                             java.lang.String keyPrefix)

Initialises a new instance of the SharedPreferencesBase.

On construction the version will be check and if found to be out of date the incremental update will be executed.

Parameters:

context - The Android Context

keyPrefix - The prefix to be used for all keys.

Method Detail

onPreCheckVersion

protected void onPreCheckVersion()

A hook to allow for subclasses to perform any tasks before the version is checked and any upgrades are done. This is package protected as we don't actually want any implementations outside of this library to perform any checks.

getSharedPreferencesName

protected java.lang.String getSharedPreferencesName()

Gets the name of the class purely for logging purposes. This will be the name of the subclass.

Returns:

The name of the subclass extending this class.

updateStoreData

protected abstract void updateStoreData(int newVersion)

Updates the SharedPreferences implementation to the new version. Exceptions thrown should not be caught as we do not want to keep updating to a new version if the previous update failed.

This will be called for every version between the currently stored version and the new implementation version. The newVersion will be incremented by 1 on each call. Classes that override this should take this into account when implementing this method as it should not directly upgrade the latest version, but rather do the proper upgrade path by upgrading from one version to the next.

After every call to this method the version stored in the SharedPreferences will be updated to the newVersion.

Parameters:

newVersion - The new version to which the SharedPreferences implementation will be updated.

setStringPreference

protected void setStringPreference(java.lang.String key,
                                   java.lang.String value)

getStringPreference

protected java.lang.String getStringPreference(java.lang.String key,
                                               java.lang.String defaultValue)

setLongPreference

protected void setLongPreference(java.lang.String key,
                                 long value)

getLongPreference

protected long getLongPreference(java.lang.String key,
                                 long defaultValue)

setIntPreference

protected void setIntPreference(java.lang.String key,
                                int value)

getIntPreference

protected int getIntPreference(java.lang.String key,
                               int defaultValue)

setBooleanPreference

protected void setBooleanPreference(java.lang.String key,
                                    boolean value)

getBooleanPreference

protected boolean getBooleanPreference(java.lang.String key,
                                       boolean defaultValue)

getStringSetPreference

protected java.util.Set<java.lang.String> getStringSetPreference(java.lang.String key,
                                                                 java.util.Set<java.lang.String> defaultValues)

setStringSetPreference

protected void setStringSetPreference(java.lang.String key,
                                      java.util.Set<java.lang.String> values)

removePreference

protected void removePreference(java.lang.String key)

contains

protected boolean contains(java.lang.String key)

setStoredVersion

protected void setStoredVersion(int newVersion)

Sets the version of the SharedPreferences. This value will be used when upgrading the SharedPreferences from an older (or non-existent) version of the SharedPreferences to a new one.

Parameters:

newVersion - The new version.

getStoredVersion

protected int getStoredVersion()

Get the currently stored version of the SharedPreferences implementation.

To get the current implementation version call getVersion().

Returns:

The currently stored version of the SharedPreferences implementation.

getVersion

protected abstract int getVersion()

Gets the current version of the SharedPreferences implementation. This is NOT the version that is currently cached, but rather the version to which the cache will be upgraded to if it is found to not be the same as the getStoredVersion().

To get the cached version use getStoredVersion().

All implementations MUST override this with the implementation version. The implementation version should only be changed in the subclass when there is a breaking change that requires extra work to upgrade to the new version.

Returns:

The version of the SharedPreferences implementation.

getSharedPreferences

protected android.content.SharedPreferences getSharedPreferences()

getSharedEditor

protected android.content.SharedPreferences.Editor getSharedEditor()

Returns:

the SharedPreferences.Editor for the default file "default_shared_prefs"

buildCompleteKey

protected java.lang.String buildCompleteKey(java.lang.String key)