io.realm

Class Realm

java.lang.Object

io.realm.Realm

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public final class Realm
extends java.lang.Object
implements java.io.Closeable

The Realm class is the storage and transactional manager of your object persistent store. It is in charge of creating instances of your RealmObjects. Objects within a Realm can be queried and read at any time. Creating, modifying, and deleting objects must be done while inside a transaction. See beginTransaction()

The transactions ensure that multiple instances (on multiple threads) can access the same objects in a consistent state with full ACID guarantees.

It is important to remember to call the close() method when done with a Realm instance. Failing to do so can lead to OutOfMemoryError as the native resources cannot be freed.

Realm instances cannot be used across different threads. This means that you have to open an instance on each thread you want to use Realm. Realm instances are cached automatically per thread using reference counting, so as long as the reference count doesn't reach zero, calling getInstance(android.content.Context) will just return the cached Realm and should be considered a lightweight operation.

For the UI thread this means that opening and closing Realms should occur in either onCreate/onDestroy or onStart/onStop.

Realm instances coordinate their state across threads using the Handler mechanism. This also means that Realm instances on threads without a Looper cannot receive updates unless refresh() is manually called.

A standard pattern for working with Realm in Android activities can be seen below:

 public class RealmActivity extends Activity {

   private Realm realm;

   \@Override
   protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.layout_main);
     realm = Realm.getInstance(this);
   }

   \@Override
   protected void onDestroy() {
     super.onDestroy();
     realm.close();
   }
 }
 

Realm supports String and byte fields containing up to 16 MB.

See Also:

ACID, Examples using Realm

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Realm.Transaction Encapsulates a Realm transaction.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	DEFAULT_REALM_NAME
protected static java.util.Map<android.os.Handler,java.lang.Integer>	handlers
protected static java.lang.ThreadLocal<java.util.Map<java.lang.Integer,Realm>>	realmsCache

Method Summary

Modifier and Type	Method and Description
void	addChangeListener(RealmChangeListener listener) Add a change listener to the Realm
<E extends RealmObject> RealmResults<E>	allObjects(java.lang.Class<E> clazz) Get all objects of a specific Class.
<E extends RealmObject> RealmResults<E>	allObjectsSorted(java.lang.Class<E> clazz, java.lang.String[] fieldNames, boolean[] sortAscending) Get all objects of a specific Class sorted by multiple fields.
<E extends RealmObject> RealmResults<E>	allObjectsSorted(java.lang.Class<E> clazz, java.lang.String fieldName, boolean sortAscending) Get all objects of a specific Class sorted by a field.
<E extends RealmObject> RealmResults<E>	allObjectsSorted(java.lang.Class<E> clazz, java.lang.String fieldName1, boolean sortAscending1, java.lang.String fieldName2, boolean sortAscending2) Get all objects of a specific class sorted by two specific field names.
<E extends RealmObject> RealmResults<E>	allObjectsSorted(java.lang.Class<E> clazz, java.lang.String fieldName1, boolean sortAscending1, java.lang.String fieldName2, boolean sortAscending2, java.lang.String fieldName3, boolean sortAscending3) Get all objects of a specific class sorted by two specific field names.
void	beginTransaction() Starts a write transaction, this must be closed with commitTransaction() or aborted by cancelTransaction().
void	cancelTransaction() Revert all writes (created, updated, or deleted objects) made in the current write transaction and end the transaction.
protected void	checkIfValid()
void	clear(java.lang.Class<?> classSpec) Remove all objects of the specified class.
void	close() Closes the Realm instance and all its resources.
void	commitTransaction() All changes since beginTransaction() are persisted to disk and the realm reverts back to being read-only.
static boolean	compactRealmFile(android.content.Context context) Compact a realm file.
static boolean	compactRealmFile(android.content.Context context, java.lang.String fileName) Compact a realm file.
<E extends RealmObject> E	copyToRealm(E object) Copies a RealmObject to the Realm instance and returns the copy.
<E extends RealmObject> java.util.List<E>	copyToRealm(java.lang.Iterable<E> objects) Copies a collection of RealmObjects to the Realm instance and returns their copy.
<E extends RealmObject> E	copyToRealmOrUpdate(E object) Updates an existing RealmObject that is identified by the same PrimaryKey or create a new copy if no existing object could be found.
<E extends RealmObject> java.util.List<E>	copyToRealmOrUpdate(java.lang.Iterable<E> objects) Updates a list of existing RealmObjects that is identified by their PrimaryKey or create a new copy if no existing object could be found.
<E extends RealmObject> void	createAllFromJson(java.lang.Class<E> clazz, java.io.InputStream inputStream) Create a Realm object for each object in a JSON array.
<E extends RealmObject> void	createAllFromJson(java.lang.Class<E> clazz, org.json.JSONArray json) Create a Realm object for each object in a JSON array.
<E extends RealmObject> void	createAllFromJson(java.lang.Class<E> clazz, java.lang.String json) Create a Realm object for each object in a JSON array.
<E extends RealmObject> E	createObject(java.lang.Class<E> clazz) Instantiates and adds a new object to the realm
<E extends RealmObject> E	createObjectFromJson(java.lang.Class<E> clazz, java.io.InputStream inputStream) Create a Realm object pre-filled with data from a JSON object.
<E extends RealmObject> E	createObjectFromJson(java.lang.Class<E> clazz, org.json.JSONObject json) Create a Realm object prefilled with data from a JSON object.
<E extends RealmObject> E	createObjectFromJson(java.lang.Class<E> clazz, java.lang.String json) Create a Realm object prefilled with data from a JSON object.
<E extends RealmObject> void	createOrUpdateAllFromJson(java.lang.Class<E> clazz, java.io.InputStream in) Tries to update a list of existing objects identified by their primary key with new JSON data.
<E extends RealmObject> void	createOrUpdateAllFromJson(java.lang.Class<E> clazz, org.json.JSONArray json) Tries to update a list of existing objects identified by their primary key with new JSON data.
<E extends RealmObject> void	createOrUpdateAllFromJson(java.lang.Class<E> clazz, java.lang.String json) Tries to update a list of existing objects identified by their primary key with new JSON data.
<E extends RealmObject> E	createOrUpdateObjectFromJson(java.lang.Class<E> clazz, java.io.InputStream in) Tries to update an existing object defined by its primary key with new JSON data.
<E extends RealmObject> E	createOrUpdateObjectFromJson(java.lang.Class<E> clazz, org.json.JSONObject json) Tries to update an existing object defined by its primary key with new JSON data.
<E extends RealmObject> E	createOrUpdateObjectFromJson(java.lang.Class<E> clazz, java.lang.String json) Tries to update an existing object defined by its primary key with new JSON data.
static boolean	deleteRealmFile(android.content.Context context) Delete the Realm file from the filesystem for the default Realm (named "default.realm").
static boolean	deleteRealmFile(android.content.Context context, java.lang.String fileName) Delete the Realm file from the filesystem for a custom named Realm.
void	executeTransaction(Realm.Transaction transaction) Executes a given transaction on the Realm.
protected void	finalize()
static Realm	getInstance(android.content.Context context) Realm static constructor for the default realm "default.realm".
static Realm	getInstance(android.content.Context context, byte[] key) Realm static constructor.
static Realm	getInstance(android.content.Context context, java.lang.String fileName) Realm static constructor.
static Realm	getInstance(android.content.Context context, java.lang.String fileName, byte[] key) Realm static constructor.
static Realm	getInstance(java.io.File writeableFolder) Realm static constructor.
static Realm	getInstance(java.io.File writeableFolder, byte[] key) Realm static constructor.
static Realm	getInstance(java.io.File writeableFolder, java.lang.String fileName) Realm static constructor.
static Realm	getInstance(java.io.File writeableFolder, java.lang.String fileName, byte[] key) Realm static constructor.
java.lang.String	getPath() Returns the absolute path to where this Realm is persisted on disk.
RealmJson	getRealmJson()
Table	getTable(java.lang.Class<?> clazz)
boolean	isAutoRefresh() Retrieve the auto-refresh status of the Realm instance.
static void	migrateRealmAtPath(java.lang.String realmPath, byte[] key, RealmMigration migration)
static void	migrateRealmAtPath(java.lang.String realmPath, byte[] key, RealmMigration migration, boolean autoUpdate)
static void	migrateRealmAtPath(java.lang.String realmPath, RealmMigration migration)
static void	migrateRealmAtPath(java.lang.String realmPath, RealmMigration migration, boolean autoRefresh)
void	refresh() Refresh the Realm instance and all the RealmResults and RealmObjects instances coming from it
void	removeAllChangeListeners() Remove all user-defined change listeners
void	removeChangeListener(RealmChangeListener listener) Remove the specified change listener
void	setAutoRefresh(boolean autoRefresh) Set the auto-refresh status of the Realm instance.
<E extends RealmObject> RealmQuery<E>	where(java.lang.Class<E> clazz) Returns a typed RealmQuery, which can be used to query for specific objects of this type
void	writeCopyTo(java.io.File destination) Write a compacted copy of the Realm to the given destination File.
void	writeEncryptedCopyTo(java.io.File destination, byte[] key) Write a compacted and encrypted copy of the Realm to the given destination File.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_REALM_NAME

public static final java.lang.String DEFAULT_REALM_NAME

See Also:

Constant Field Values

realmsCache

protected static final java.lang.ThreadLocal<java.util.Map<java.lang.Integer,Realm>> realmsCache

handlers

protected static final java.util.Map<android.os.Handler,java.lang.Integer> handlers

Method Detail

checkIfValid

protected void checkIfValid()

finalize

protected void finalize()
                 throws java.lang.Throwable

Overrides:

finalize in class java.lang.Object

Throws:

java.lang.Throwable

close

public void close()

Closes the Realm instance and all its resources.

It's important to always remember to close Realm instances when you're done with it in order not to leak memory, file descriptors or grow the size of Realm file out of measure.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

getRealmJson

public RealmJson getRealmJson()

isAutoRefresh

public boolean isAutoRefresh()

Retrieve the auto-refresh status of the Realm instance.

Returns:

the auto-refresh status

setAutoRefresh

public void setAutoRefresh(boolean autoRefresh)

Set the auto-refresh status of the Realm instance.

Auto-refresh is a feature that enables automatic update of the current realm instance and all its derived objects (RealmResults and RealmObjects instances) when a commit is performed on a Realm acting on the same file in another thread. This feature is only available if the realm instance lives is a Looper enabled thread.

Parameters:

autoRefresh - true will turn auto-refresh on, false will turn it off.

Throws:

java.lang.IllegalStateException - if trying to enable auto-refresh in a thread without Looper.

getTable

public Table getTable(java.lang.Class<?> clazz)

getInstance

public static Realm getInstance(android.content.Context context)

Realm static constructor for the default realm "default.realm". close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

context - an Android Context

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(android.content.Context context,
                                java.lang.String fileName)

Realm static constructor. close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

context - an Android Context

fileName - the name of the file to save the Realm to

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(android.content.Context context,
                                byte[] key)

Realm static constructor. close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

context - an Android Context

key - a 64-byte encryption key

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(android.content.Context context,
                                java.lang.String fileName,
                                byte[] key)

Realm static constructor. close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

context - an Android Context

key - a 64-byte encryption key

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(java.io.File writeableFolder)

Realm static constructor. close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

writeableFolder - a File object representing a writeable folder

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(java.io.File writeableFolder,
                                java.lang.String fileName)

Realm static constructor. close() It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

writeableFolder - a File object representing a writeable folder

fileName - the name of the Realm file

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(java.io.File writeableFolder,
                                byte[] key)

Realm static constructor. close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

writeableFolder - a File object representing a writeable folder

key - a 64-byte encryption key

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

getInstance

public static Realm getInstance(java.io.File writeableFolder,
                                java.lang.String fileName,
                                byte[] key)

Realm static constructor. close() must be called when you are done using the Realm instance.

It sets auto-refresh on if the current thread has a Looper, off otherwise.

Parameters:

writeableFolder - a File object representing a writeable folder

fileName - the name of the Realm file

key - a 64-byte encryption key

Returns:

an instance of the Realm class

Throws:

RealmMigrationNeededException - The model classes have been changed and the Realm must be migrated

RealmIOException - Error when accessing underlying file

RealmException - Other errors

createAllFromJson

public <E extends RealmObject> void createAllFromJson(java.lang.Class<E> clazz,
                                                      org.json.JSONArray json)

Create a Realm object for each object in a JSON array. This must be done within a transaction. JSON properties with a null value will map to the default value for the data type in Realm and unknown properties will be ignored.

Parameters:

clazz - Type of Realm objects to create.

json - Array where each JSONObject must map to the specified class.

Throws:

RealmException - if mapping from JSON fails.

createOrUpdateAllFromJson

public <E extends RealmObject> void createOrUpdateAllFromJson(java.lang.Class<E> clazz,
                                                              org.json.JSONArray json)

Tries to update a list of existing objects identified by their primary key with new JSON data. If an existing object could not be found in the Realm, a new object will be created. This must happen within a transaction.

Parameters:

clazz - Type of RealmObject to create or update. It must have a primary key defined.

json - Array with object data.

Throws:

java.lang.IllegalArgumentException - if trying to update a class without a PrimaryKey.

See Also:

createAllFromJson(Class, org.json.JSONArray)

createAllFromJson

public <E extends RealmObject> void createAllFromJson(java.lang.Class<E> clazz,
                                                      java.lang.String json)

Create a Realm object for each object in a JSON array. This must be done within a transaction. JSON properties with a null value will map to the default value for the data type in Realm and unknown properties will be ignored.

Parameters:

clazz - Type of Realm objects to create.

json - JSON array as a String where each object can map to the specified class.

Throws:

RealmException - if mapping from JSON fails.

createOrUpdateAllFromJson

public <E extends RealmObject> void createOrUpdateAllFromJson(java.lang.Class<E> clazz,
                                                              java.lang.String json)

Tries to update a list of existing objects identified by their primary key with new JSON data. If an existing object could not be found in the Realm, a new object will be created. This must happen within a transaction.

Parameters:

clazz - Type of RealmObject to create or update. It must have a primary key defined.

json - String with an array of JSON objects.

Throws:

java.lang.IllegalArgumentException - if trying to update a class without a PrimaryKey.

See Also:

createAllFromJson(Class, String)

createAllFromJson

public <E extends RealmObject> void createAllFromJson(java.lang.Class<E> clazz,
                                                      java.io.InputStream inputStream)
                                               throws java.io.IOException

Create a Realm object for each object in a JSON array. This must be done within a transaction. JSON properties with a null value will map to the default value for the data type in Realm and unknown properties will be ignored.

Parameters:

clazz - Type of Realm objects created.

inputStream - JSON array as a InputStream. All objects in the array must be of the specified class.

Throws:

RealmException - if mapping from JSON fails.

java.io.IOException - if something was wrong with the input stream.

createOrUpdateAllFromJson

public <E extends RealmObject> void createOrUpdateAllFromJson(java.lang.Class<E> clazz,
                                                              java.io.InputStream in)
                                                       throws java.io.IOException

Tries to update a list of existing objects identified by their primary key with new JSON data. If an existing object could not be found in the Realm, a new object will be created. This must happen within a transaction.

Parameters:

clazz - Type of RealmObject to create or update. It must have a primary key defined.

in - InputStream with a list of object data in JSON format.

Throws:

java.lang.IllegalArgumentException - if trying to update a class without a PrimaryKey.

java.io.IOException

See Also:

createOrUpdateAllFromJson(Class, java.io.InputStream)

createObjectFromJson

public <E extends RealmObject> E createObjectFromJson(java.lang.Class<E> clazz,
                                                      org.json.JSONObject json)

Create a Realm object prefilled with data from a JSON object. This must be done inside a transaction. JSON properties with a null value will map to the default value for the data type in Realm and unknown properties will be ignored.

Parameters:

clazz - Type of Realm object to create.

json - JSONObject with object data.

Returns:

Created object or null if no json data was provided.

Throws:

RealmException - if the mapping from JSON fails.

See Also:

createOrUpdateObjectFromJson(Class, org.json.JSONObject)

createOrUpdateObjectFromJson

public <E extends RealmObject> E createOrUpdateObjectFromJson(java.lang.Class<E> clazz,
                                                              org.json.JSONObject json)

Tries to update an existing object defined by its primary key with new JSON data. If no existing object could be found a new object will be saved in the Realm. This must happen within a transaction.

Parameters:

clazz - Type of RealmObject to create or update. It must have a primary key defined.

json - JSONObject with object data.

Returns:

Created or updated RealmObject.

Throws:

java.lang.IllegalArgumentException - if trying to update a class without a PrimaryKey.

See Also:

createObjectFromJson(Class, org.json.JSONObject)

createObjectFromJson

public <E extends RealmObject> E createObjectFromJson(java.lang.Class<E> clazz,
                                                      java.lang.String json)

Create a Realm object prefilled with data from a JSON object. This must be done inside a transaction. JSON properties with a null value will map to the default value for the data type in Realm and unknown properties will be ignored.

Parameters:

clazz - Type of Realm object to create.

json - JSON string with object data.

Returns:

Created object or null if json string was empty or null.

Throws:

RealmException - if mapping to json failed.

createOrUpdateObjectFromJson

public <E extends RealmObject> E createOrUpdateObjectFromJson(java.lang.Class<E> clazz,
                                                              java.lang.String json)

Tries to update an existing object defined by its primary key with new JSON data. If no existing object could be found a new object will be saved in the Realm. This must happen within a transaction.

Parameters:

clazz - Type of RealmObject to create or update. It must have a primary key defined.

json - String with object data in JSON format.

Returns:

Created or updated RealmObject.

Throws:

java.lang.IllegalArgumentException - if trying to update a class without a PrimaryKey.

See Also:

createObjectFromJson(Class, String)

createObjectFromJson

public <E extends RealmObject> E createObjectFromJson(java.lang.Class<E> clazz,
                                                      java.io.InputStream inputStream)
                                               throws java.io.IOException

Create a Realm object pre-filled with data from a JSON object. This must be done inside a transaction. JSON properties with a null value will map to the default value for the data type in Realm and unknown properties will be ignored.

Parameters:

clazz - Type of Realm object to create.

inputStream - JSON object data as a InputStream.

Returns:

Created object or null if json string was empty or null.

Throws:

RealmException - if the mapping from JSON failed.

java.io.IOException - if something was wrong with the input stream.

createOrUpdateObjectFromJson

public <E extends RealmObject> E createOrUpdateObjectFromJson(java.lang.Class<E> clazz,
                                                              java.io.InputStream in)
                                                       throws java.io.IOException

Tries to update an existing object defined by its primary key with new JSON data. If no existing object could be found a new object will be saved in the Realm. This must happen within a transaction.

Parameters:

clazz - Type of RealmObject to create or update. It must have a primary key defined.

in - Inputstream with object data in JSON format.

Returns:

Created or updated RealmObject.

Throws:

java.lang.IllegalArgumentException - if trying to update a class without a PrimaryKey.

java.io.IOException

See Also:

createObjectFromJson(Class, java.io.InputStream)

writeCopyTo

public void writeCopyTo(java.io.File destination)
                 throws java.io.IOException

Write a compacted copy of the Realm to the given destination File.

The destination file cannot already exist.

Note that if this is called from within a write transaction it writes the current data, and not the data as it was when the last write transaction was committed.

Parameters:

destination - File to save the Realm to

Throws:

java.io.IOException - if any write operation fails

writeEncryptedCopyTo

public void writeEncryptedCopyTo(java.io.File destination,
                                 byte[] key)
                          throws java.io.IOException

Write a compacted and encrypted copy of the Realm to the given destination File.

The destination file cannot already exist.

Note that if this is called from within a write transaction it writes the current data, and not the data as it was when the last write transaction was committed.

Parameters:

destination - File to save the Realm to

Throws:

java.io.IOException - if any write operation fails

createObject

public <E extends RealmObject> E createObject(java.lang.Class<E> clazz)

Instantiates and adds a new object to the realm

Parameters:

clazz - The Class of the object to create

Returns:

The new object

Throws:

RealmException - An object could not be created

copyToRealm

public <E extends RealmObject> E copyToRealm(E object)

Copies a RealmObject to the Realm instance and returns the copy. Any further changes to the original RealmObject will not be reflected in the Realm copy.

Parameters:

object - RealmObject to copy to the Realm.

Returns:

A managed RealmObject with its properties backed by the Realm.

Throws:

java.lang.IllegalArgumentException - if RealmObject is null.

copyToRealmOrUpdate

public <E extends RealmObject> E copyToRealmOrUpdate(E object)

Updates an existing RealmObject that is identified by the same PrimaryKey or create a new copy if no existing object could be found.

Parameters:

object - RealmObject to copy or update.

Returns:

The new or updated RealmObject with all its properties backed by the Realm.

Throws:

java.lang.IllegalArgumentException - if RealmObject is null or doesn't have a Primary key defined.

See Also:

copyToRealm(RealmObject)

copyToRealm

public <E extends RealmObject> java.util.List<E> copyToRealm(java.lang.Iterable<E> objects)

Copies a collection of RealmObjects to the Realm instance and returns their copy. Any further changes to the original RealmObjects will not be reflected in the Realm copies.

Parameters:

objects - RealmObjects to copy to the Realm.

Returns:

A list of the the converted RealmObjects that all has their properties managed by the Realm.

Throws:

RealmException - if any of the objects has already been added to Realm.

java.lang.IllegalArgumentException - if any of the elements in the input collection is null.

copyToRealmOrUpdate

public <E extends RealmObject> java.util.List<E> copyToRealmOrUpdate(java.lang.Iterable<E> objects)

Updates a list of existing RealmObjects that is identified by their PrimaryKey or create a new copy if no existing object could be found.

Parameters:

objects - List of objects to update or copy into Realm.

Returns:

A list of all the new or updated RealmObjects.

Throws:

java.lang.IllegalArgumentException - if RealmObject is null or doesn't have a Primary key defined.

See Also:

copyToRealm(Iterable)

where

public <E extends RealmObject> RealmQuery<E> where(java.lang.Class<E> clazz)

Returns a typed RealmQuery, which can be used to query for specific objects of this type

Parameters:

clazz - The class of the object which is to be queried for

Returns:

A typed RealmQuery, which can be used to query for specific objects of this type

Throws:

java.lang.RuntimeException - Any other error

See Also:

RealmQuery

allObjects

public <E extends RealmObject> RealmResults<E> allObjects(java.lang.Class<E> clazz)

Get all objects of a specific Class. If no objects exist, the returned RealmResults will not be null. The RealmResults.size() to check the number of objects instead.

Parameters:

clazz - the Class to get objects of

Returns:

A RealmResult list containing the objects

Throws:

java.lang.RuntimeException - Any other error

See Also:

RealmResults

allObjectsSorted

public <E extends RealmObject> RealmResults<E> allObjectsSorted(java.lang.Class<E> clazz,
                                                                java.lang.String fieldName,
                                                                boolean sortAscending)

Get all objects of a specific Class sorted by a field. If no objects exist, the returned RealmResults will not be null. The RealmResults.size() to check the number of objects instead.

Parameters:

clazz - the Class to get objects of.

fieldName - the field name to sort by.

sortAscending - sort ascending if SORT_ORDER_ASCENDING, sort descending if SORT_ORDER_DESCENDING.

Returns:

A sorted RealmResults containing the objects.

Throws:

java.lang.IllegalArgumentException - if field name does not exist.

allObjectsSorted

public <E extends RealmObject> RealmResults<E> allObjectsSorted(java.lang.Class<E> clazz,
                                                                java.lang.String fieldName1,
                                                                boolean sortAscending1,
                                                                java.lang.String fieldName2,
                                                                boolean sortAscending2)

Get all objects of a specific class sorted by two specific field names. If no objects exist, the returned RealmResults will not be null. The RealmResults.size() to check the number of objects instead.

Parameters:

clazz - the class ti get objects of.

fieldName1 - first field name to sort by.

sortAscending1 - sort order for first field.

fieldName2 - second field name to sort by.

sortAscending2 - sort order for second field.

Returns:

A sorted RealmResults containing the objects.

Throws:

java.lang.IllegalArgumentException - if a field name does not exist.

allObjectsSorted

public <E extends RealmObject> RealmResults<E> allObjectsSorted(java.lang.Class<E> clazz,
                                                                java.lang.String fieldName1,
                                                                boolean sortAscending1,
                                                                java.lang.String fieldName2,
                                                                boolean sortAscending2,
                                                                java.lang.String fieldName3,
                                                                boolean sortAscending3)

Get all objects of a specific class sorted by two specific field names. If no objects exist, the returned RealmResults will not be null. The RealmResults.size() to check the number of objects instead.

Parameters:

clazz - the class ti get objects of.

fieldName1 - first field name to sort by.

sortAscending1 - sort order for first field.

fieldName2 - second field name to sort by.

sortAscending2 - sort order for second field.

fieldName3 - third field name to sort by.

sortAscending3 - sort order for third field.

Returns:

A sorted RealmResults containing the objects.

Throws:

java.lang.IllegalArgumentException - if a field name does not exist.

allObjectsSorted

public <E extends RealmObject> RealmResults<E> allObjectsSorted(java.lang.Class<E> clazz,
                                                                java.lang.String[] fieldNames,
                                                                boolean[] sortAscending)

Get all objects of a specific Class sorted by multiple fields. If no objects exist, the returned RealmResults will not be null. The RealmResults.size() to check the number of objects instead.

Parameters:

clazz - the Class to get objects of.

sortAscending - sort ascending if SORT_ORDER_ASCENDING, sort descending if SORT_ORDER_DESCENDING.

fieldNames - an array of fieldnames to sort objects by. The objects are first sorted by fieldNames[0], then by fieldNames[1] and so forth.

Returns:

A sorted RealmResults containing the objects.

Throws:

java.lang.IllegalArgumentException - if a field name does not exist.

addChangeListener

public void addChangeListener(RealmChangeListener listener)

Add a change listener to the Realm

Parameters:

listener - the change listener

See Also:

RealmChangeListener

removeChangeListener

public void removeChangeListener(RealmChangeListener listener)

Remove the specified change listener

Parameters:

listener - the change listener to be removed

See Also:

RealmChangeListener

removeAllChangeListeners

public void removeAllChangeListeners()

Remove all user-defined change listeners

See Also:

RealmChangeListener

refresh

public void refresh()

Refresh the Realm instance and all the RealmResults and RealmObjects instances coming from it

beginTransaction

public void beginTransaction()

Starts a write transaction, this must be closed with commitTransaction() or aborted by cancelTransaction(). Write transactions are used to atomically create, update and delete objects within a realm.
Before beginning the write transaction, beginTransaction() updates the realm in the case of pending updates from other threads.
Notice: it is not possible to nest write transactions. If you start a write transaction within a write transaction an exception is thrown.

Throws:

java.lang.IllegalStateException - If already in a write transaction or incorrect thread.

commitTransaction

public void commitTransaction()

All changes since beginTransaction() are persisted to disk and the realm reverts back to being read-only. An event is sent to notify all other realm instances that a change has occurred. When the event is received, the other realms will get their objects and RealmResults updated to reflect the changes from this commit.

Throws:

java.lang.IllegalStateException - If the write transaction is in an invalid state or incorrect thread.

cancelTransaction

public void cancelTransaction()

Revert all writes (created, updated, or deleted objects) made in the current write transaction and end the transaction.
The realm reverts back to read-only.
Calling this when not in a write transaction will throw an exception.

Throws:

java.lang.IllegalStateException - If the write transaction is an invalid state, not in a write transaction or incorrect thread.

executeTransaction

public void executeTransaction(Realm.Transaction transaction)

Executes a given transaction on the Realm. beginTransaction() and commitTransaction() will be called automatically. If any exception is thrown during the transaction cancelTransaction() will be called instead of commitTransaction().

Parameters:

transaction - Realm.Transaction to execute.

Throws:

RealmException - if any error happened during the transaction.

clear

public void clear(java.lang.Class<?> classSpec)

Remove all objects of the specified class.

Parameters:

classSpec - The class which objects should be removed

Throws:

java.lang.RuntimeException - Any other error

migrateRealmAtPath

public static void migrateRealmAtPath(java.lang.String realmPath,
                                      RealmMigration migration)

migrateRealmAtPath

public static void migrateRealmAtPath(java.lang.String realmPath,
                                      byte[] key,
                                      RealmMigration migration)

migrateRealmAtPath

public static void migrateRealmAtPath(java.lang.String realmPath,
                                      RealmMigration migration,
                                      boolean autoRefresh)

migrateRealmAtPath

public static void migrateRealmAtPath(java.lang.String realmPath,
                                      byte[] key,
                                      RealmMigration migration,
                                      boolean autoUpdate)

deleteRealmFile

public static boolean deleteRealmFile(android.content.Context context)

Delete the Realm file from the filesystem for the default Realm (named "default.realm"). The realm must be unused and closed before calling this method. WARNING: Your Realm must not be open (typically when your app launch).

Parameters:

context - an Android Context.

Returns:

false if a file could not be deleted. The failing file will be logged.

See Also:

clear(Class)

deleteRealmFile

public static boolean deleteRealmFile(android.content.Context context,
                                      java.lang.String fileName)

Delete the Realm file from the filesystem for a custom named Realm. The realm must be unused and closed before calling this method.

Parameters:

context - an Android Context.

fileName - the name of the custom Realm (i.e. "myCustomRealm.realm").

Returns:

false if a file could not be deleted. The failing file will be logged.

compactRealmFile

public static boolean compactRealmFile(android.content.Context context,
                                       java.lang.String fileName)

Compact a realm file. A realm file usually contain free/unused space. This method removes this free space and the file size is thereby reduced. Objects within the realm files are untouched.

The file must be closed before this method is called.
The file system should have free space for at least a copy of the realm file.
The realm file is left untouched if any file operation fails.

Parameters:

context - an Android Context

fileName - the name of the file to compact

Returns:

true if successful, false if any file operation failed

compactRealmFile

public static boolean compactRealmFile(android.content.Context context)

Compact a realm file. A realm file usually contain free/unused space. This method removes this free space and the file size is thereby reduced. Objects within the realm files are untouched.

The file must be closed before this method is called.
The file system should have free space for at least a copy of the realm file.
The realm file is left untouched if any file operation fails.

Parameters:

context - an Android Context

Returns:

true if successful, false if any file operation failed

getPath

public java.lang.String getPath()

Returns the absolute path to where this Realm is persisted on disk.

Returns:

The absolute path to the realm file.