public class Realm extends Object
executeTransaction(Transaction)
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(RealmConfiguration) 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 waitForChange()
is manually called.
A standard pattern for working with Realm in Android activities can be seen below:
public class RealmApplication extends Application {
\@Override
public void onCreate() {
super.onCreate();
// The Realm file will be located in package's "files" directory.
RealmConfiguration realmConfig = new RealmConfiguration.Builder(this).build();
Realm.setDefaultConfiguration(realmConfig);
}
}
public class RealmActivity extends Activity {
private Realm realm;
\@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_main);
realm = Realm.getDefaultInstance();
}
\@Override
protected void onDestroy() {
super.onDestroy();
realm.close();
}
}
Realm supports String and byte fields containing up to 16 MB.
| Modifier and Type | Class and Description |
|---|---|
static class |
io.realm.BaseRealm.InstanceCallback<T extends io.realm.BaseRealm>
The Callback used when reporting back the result of loading a Realm asynchronously using either
getInstanceAsync(RealmConfiguration, Realm.Callback) or
DynamicRealm.getInstanceAsync(RealmConfiguration, DynamicRealm.Callback). |
static class |
io.realm.BaseRealm.RealmObjectContext |
static class |
Realm.Callback
The Callback used when reporting back the result of loading a Realm asynchronously using either
getInstanceAsync(RealmConfiguration, Realm.Callback) or
DynamicRealm.getInstanceAsync(RealmConfiguration, DynamicRealm.Callback). |
static interface |
Realm.Transaction
Encapsulates a Realm transaction.
|
| Modifier and Type | Field and Description |
|---|---|
static String |
DEFAULT_REALM_NAME |
static io.realm.BaseRealm.ThreadLocalRealmObjectContext |
objectContext |
| Modifier and Type | Method and Description |
|---|---|
void |
addChangeListener(RealmChangeListener<Realm> listener)
Adds a change listener to the Realm.
|
<any> |
asObservable()
Returns an RxJava Observable that monitors changes to this Realm.
|
void |
beginTransaction()
Starts a transaction which must be closed by
BaseRealm.commitTransaction() or aborted by
BaseRealm.cancelTransaction(). |
void |
cancelTransaction()
Reverts all writes (created, updated, or deleted objects) made in the current write transaction and end the
transaction.
|
void |
close()
Closes the Realm instance and all its resources.
|
void |
commitTransaction()
All changes since
BaseRealm.beginTransaction() are persisted to disk and the Realm reverts back to
being read-only. |
static boolean |
compactRealm(RealmConfiguration configuration)
Compacts a Realm file.
|
<E extends RealmModel> |
copyFromRealm(E realmObject)
Makes an unmanaged in-memory copy of an already persisted
RealmObject. |
<E extends RealmModel> |
copyFromRealm(E realmObject,
int maxDepth)
Makes an unmanaged in-memory copy of an already persisted
RealmObject. |
<E extends RealmModel> |
copyFromRealm(Iterable<E> realmObjects)
Makes an unmanaged in-memory copy of already persisted RealmObjects.
|
<E extends RealmModel> |
copyFromRealm(Iterable<E> realmObjects,
int maxDepth)
Makes an unmanaged in-memory copy of already persisted RealmObjects.
|
<E extends RealmModel> |
copyToRealm(E object)
Copies a RealmObject to the Realm instance and returns the copy.
|
<E extends RealmModel> |
copyToRealm(Iterable<E> objects)
Copies a collection of RealmObjects to the Realm instance and returns their copy.
|
<E extends RealmModel> |
copyToRealmOrUpdate(E object)
Updates an existing RealmObject that is identified by the same
PrimaryKey or creates
a new copy if no existing object could be found. |
<E extends RealmModel> |
copyToRealmOrUpdate(Iterable<E> objects)
Updates a list of existing RealmObjects that is identified by their
PrimaryKey or
creates a new copy if no existing object could be found. |
<E extends RealmModel> |
createAllFromJson(Class<E> clazz,
InputStream inputStream)
Creates a Realm object for each object in a JSON array.
|
<E extends RealmModel> |
createAllFromJson(Class<E> clazz,
JSONArray json)
Creates a Realm object for each object in a JSON array.
|
<E extends RealmModel> |
createAllFromJson(Class<E> clazz,
String json)
Creates a Realm object for each object in a JSON array.
|
<E extends RealmModel> |
createObject(Class<E> clazz)
Instantiates and adds a new object to the Realm.
|
<E extends RealmModel> |
createObject(Class<E> clazz,
Object primaryKeyValue)
Instantiates and adds a new object to the Realm with the primary key value already set.
|
<E extends RealmModel> |
createObjectFromJson(Class<E> clazz,
InputStream inputStream)
Creates a Realm object pre-filled with data from a JSON object.
|
<E extends RealmModel> |
createObjectFromJson(Class<E> clazz,
JSONObject json)
Creates a Realm object pre-filled with data from a JSON object.
|
<E extends RealmModel> |
createObjectFromJson(Class<E> clazz,
String json)
Creates a Realm object pre-filled with data from a JSON object.
|
<E extends RealmModel> |
createOrUpdateAllFromJson(Class<E> clazz,
InputStream in)
Tries to update a list of existing objects identified by their primary key with new JSON data.
|
<E extends RealmModel> |
createOrUpdateAllFromJson(Class<E> clazz,
JSONArray json)
Tries to update a list of existing objects identified by their primary key with new JSON data.
|
<E extends RealmModel> |
createOrUpdateAllFromJson(Class<E> clazz,
String json)
Tries to update a list of existing objects identified by their primary key with new JSON data.
|
<E extends RealmModel> |
createOrUpdateObjectFromJson(Class<E> clazz,
InputStream in)
Tries to update an existing object defined by its primary key with new JSON data.
|
<E extends RealmModel> |
createOrUpdateObjectFromJson(Class<E> clazz,
JSONObject json)
Tries to update an existing object defined by its primary key with new JSON data.
|
<E extends RealmModel> |
createOrUpdateObjectFromJson(Class<E> clazz,
String json)
Tries to update an existing object defined by its primary key with new JSON data.
|
void |
delete(Class<? extends RealmModel> clazz)
Deletes all objects of the specified class from the Realm.
|
void |
deleteAll()
Deletes all objects from this Realm.
|
static boolean |
deleteRealm(RealmConfiguration configuration)
Deletes the Realm file specified by the given
RealmConfiguration from the filesystem. |
void |
executeTransaction(Realm.Transaction transaction)
Executes a given transaction on the Realm.
|
RealmAsyncTask |
executeTransactionAsync(Realm.Transaction transaction)
Similar to
executeTransaction(Transaction) but runs asynchronously on a worker thread. |
RealmAsyncTask |
executeTransactionAsync(Realm.Transaction transaction,
Realm.Transaction.OnError onError)
Similar to
executeTransactionAsync(Transaction), but also accepts an OnError callback. |
RealmAsyncTask |
executeTransactionAsync(Realm.Transaction transaction,
Realm.Transaction.OnSuccess onSuccess)
Similar to
executeTransactionAsync(Transaction), but also accepts an OnSuccess callback. |
RealmAsyncTask |
executeTransactionAsync(Realm.Transaction transaction,
Realm.Transaction.OnSuccess onSuccess,
Realm.Transaction.OnError onError)
Similar to
executeTransactionAsync(Transaction), but also accepts an OnSuccess and OnError callbacks. |
RealmConfiguration |
getConfiguration()
Returns the
RealmConfiguration for this Realm. |
static RealmConfiguration |
getDefaultConfiguration()
Returns the default configuration for
getDefaultInstance(). |
static Realm |
getDefaultInstance()
Realm static constructor that returns the Realm instance defined by the
RealmConfiguration set
by setDefaultConfiguration(RealmConfiguration) |
static Object |
getDefaultModule()
Returns the default Realm module.
|
static int |
getGlobalInstanceCount(RealmConfiguration configuration)
Returns the current number of open Realm instances across all threads that are using this configuration.
|
static Realm |
getInstance(RealmConfiguration configuration)
Realm static constructor that returns the Realm instance defined by provided
RealmConfiguration |
static RealmAsyncTask |
getInstanceAsync(RealmConfiguration configuration,
Realm.Callback callback)
The creation of the first Realm instance per
RealmConfiguration in a process can take some time as all
initialization code need to run at that point (setting up the Realm, validating schemas and creating initial
data). |
static int |
getLocalInstanceCount(RealmConfiguration configuration)
Returns the current number of open Realm instances on the thread calling this method.
|
String |
getPath()
Returns the canonical path to where this Realm is persisted on disk.
|
RealmSchema |
getSchema()
Returns the schema for this Realm.
|
long |
getVersion()
Returns the schema version for this Realm.
|
static void |
init(Context context)
Initializes the Realm library and creates a default configuration that is ready to use.
|
void |
insert(Collection<? extends RealmModel> objects)
Inserts a list of an unmanaged RealmObjects.
|
void |
insert(RealmModel object)
Inserts an unmanaged RealmObject.
|
void |
insertOrUpdate(Collection<? extends RealmModel> objects)
Inserts or updates a list of unmanaged RealmObjects.
|
void |
insertOrUpdate(RealmModel object)
Inserts or updates an unmanaged RealmObject.
|
boolean |
isAutoRefresh()
Retrieves the auto-refresh status of the Realm instance.
|
boolean |
isClosed()
Checks if the
Realm instance has already been closed. |
boolean |
isEmpty()
Checks if this
Realm contains any objects. |
boolean |
isInTransaction()
Checks if the Realm is currently in a transaction.
|
static void |
migrateRealm(RealmConfiguration configuration)
Manually triggers the migration associated with a given RealmConfiguration.
|
static void |
migrateRealm(RealmConfiguration configuration,
RealmMigration migration)
Manually triggers a migration on a RealmMigration.
|
void |
refresh()
Refreshes the Realm instance and all the RealmResults and RealmObjects instances coming from it.
|
void |
removeAllChangeListeners()
Removes all user-defined change listeners.
|
void |
removeChangeListener(RealmChangeListener<Realm> listener)
Removes the specified change listener.
|
static void |
removeDefaultConfiguration()
Removes the current default configuration (if any).
|
void |
setAutoRefresh(boolean autoRefresh)
Sets the auto-refresh status of the Realm instance.
|
static void |
setDefaultConfiguration(RealmConfiguration configuration)
Sets the
RealmConfiguration used when calling getDefaultInstance(). |
void |
stopWaitForChange()
Makes any current
waitForChange() return false immediately. |
boolean |
waitForChange()
Blocks the current thread until new changes to the Realm are available or
stopWaitForChange()
is called from another thread. |
<E extends RealmModel> |
where(Class<E> clazz)
Returns a typed RealmQuery, which can be used to query for specific objects of this type
|
void |
writeCopyTo(File destination)
Writes a compacted copy of the Realm to the given destination File.
|
void |
writeEncryptedCopyTo(File destination,
byte[] key)
Writes a compacted and encrypted copy of the Realm to the given destination File.
|
public static final String DEFAULT_REALM_NAME
public static final io.realm.BaseRealm.ThreadLocalRealmObjectContext objectContext
public <any> asObservable()
onComplete will never be called.
If you would like the asObservable() to stop emitting items, you can instruct RxJava to
only emit only the first item by using the first() operator:
realm.asObservable().first().subscribe( ... ) // You only get the results once
onNext. It will never call onComplete or OnError.public static void init(Context context)
A good place is in an Application subclass:
public class MyApplication extends Application {
\@Override
public void onCreate() {
super.onCreate();
Realm.init(this);
}
}
Remember to register it in the AndroidManifest.xml file:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="io.realm.example">
<application android:name=".MyApplication">
// ...
</application>
</manifest>
context - the Application Context.IllegalArgumentException - if a null context is provided.IllegalStateException - if Context.getFilesDir() could not be found.getDefaultInstance()public static Realm getDefaultInstance()
RealmConfiguration set
by setDefaultConfiguration(RealmConfiguration)NullPointerException - if no default configuration has been defined.RealmMigrationNeededException - if no migration has been provided by the default configuration and the
RealmObject classes or version has has changed so a migration is required.RealmFileException - if an error happened when accessing the underlying Realm file.DownloadingRealmInterruptedException - if SyncConfiguration.Builder.waitForInitialRemoteData()
was set and the thread opening the Realm was interrupted while the download was in progress.public static Realm getInstance(RealmConfiguration configuration)
RealmConfigurationconfiguration - RealmConfiguration used to open the RealmRealmMigrationNeededException - if no migration has been provided by the configuration and the RealmObject
classes or version has has changed so a migration is required.RealmFileException - if an error happened when accessing the underlying Realm file.IllegalArgumentException - if a null RealmConfiguration is provided.DownloadingRealmInterruptedException - if SyncConfiguration.Builder.waitForInitialRemoteData()
was set and the thread opening the Realm was interrupted while the download was in progress.for details on how to configure a Realm.public static RealmAsyncTask getInstanceAsync(RealmConfiguration configuration, Realm.Callback callback)
RealmConfiguration in a process can take some time as all
initialization code need to run at that point (setting up the Realm, validating schemas and creating initial
data). This method places the initialization work in a background thread and deliver the Realm instance
to the caller thread asynchronously after the initialization is finished.configuration - RealmConfiguration used to open the Realm.callback - invoked to return the results.RealmAsyncTask representing a cancellable task.IllegalArgumentException - if a null RealmConfiguration or a null Realm.Transaction.Callback is provided.IllegalStateException - if it is called from a non-Looper or IntentService thread.for more details.public static void setDefaultConfiguration(RealmConfiguration configuration)
RealmConfiguration used when calling getDefaultInstance().configuration - the RealmConfiguration to use as the default configuration.IllegalArgumentException - if a null RealmConfiguration is provided.for details on how to configure a Realm.public static RealmConfiguration getDefaultConfiguration()
getDefaultInstance().null if no default configuration is specified.public static void removeDefaultConfiguration()
getDefaultInstance() will
fail until a new default configuration has been set using setDefaultConfiguration(RealmConfiguration).public <E extends RealmModel> void createAllFromJson(Class<E> clazz, JSONArray json)
JSON properties with unknown properties will be ignored. If a RealmObject field is not present in the
JSON object the RealmObject field will be set to the default value for that type.
clazz - type of Realm objects to create.json - an array where each JSONObject must map to the specified class.RealmException - if mapping from JSON fails.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.public <E extends RealmModel> void createOrUpdateAllFromJson(Class<E> clazz, JSONArray json)
RealmObject and a field is not found in the JSON object, that field will not be updated. If
a new RealmObject is created and a field is not found in the JSON object, that field will be assigned the
default value for the field type.clazz - type of RealmObject to create or update. It must have a primary key defined.json - array with object data.IllegalArgumentException - if trying to update a class without a PrimaryKey.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.RealmException - if unable to map JSON.createAllFromJson(Class, org.json.JSONArray)public <E extends RealmModel> void createAllFromJson(Class<E> clazz, String json)
RealmObject field is not present in the
JSON object the RealmObject field will be set to the default value for that type.clazz - type of Realm objects to create.json - the JSON array as a String where each object can map to the specified class.RealmException - if mapping from JSON fails.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.public <E extends RealmModel> void createOrUpdateAllFromJson(Class<E> clazz, String json)
RealmObject and a field is not found in the JSON object, that field will not be updated.
If a new RealmObject is created and a field is not found in the JSON object, that field will be assigned
the default value for the field type.clazz - type of RealmObject to create or update. It must have a primary key defined.json - string with an array of JSON objects.IllegalArgumentException - if trying to update a class without a PrimaryKey.RealmException - if unable to create a JSON array from the json string.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.createAllFromJson(Class, String)public <E extends RealmModel> void createAllFromJson(Class<E> clazz, InputStream inputStream) throws IOException
RealmObject field is not present in the
JSON object the RealmObject field will be set to the default value for that type.
This API is only available in API level 11 or later.
clazz - type of Realm objects created.inputStream - the JSON array as a InputStream. All objects in the array must be of the specified class.RealmException - if mapping from JSON fails.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.IOException - if something was wrong with the input stream.public <E extends RealmModel> void createOrUpdateAllFromJson(Class<E> clazz, InputStream in)
RealmObject and a field is not found in the JSON object, that field will not be updated.
If a new RealmObject is created and a field is not found in the JSON object, that field will be assigned
the default value for the field type.
This API is only available in API level 11 or later.
clazz - type of RealmObject to create or update. It must have a primary key defined.in - the InputStream with a list of object data in JSON format.IllegalArgumentException - if trying to update a class without a PrimaryKey.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.RealmException - if unable to read JSON.createOrUpdateAllFromJson(Class, java.io.InputStream)public <E extends RealmModel> E createObjectFromJson(Class<E> clazz, JSONObject json)
RealmObject field is not present in the JSON
object the RealmObject field will be set to the default value for that type.clazz - type of Realm object to create.json - the JSONObject with object data.null if no JSON data was provided.RealmException - if the mapping from JSON fails.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.createOrUpdateObjectFromJson(Class, org.json.JSONObject)public <E extends RealmModel> E createOrUpdateObjectFromJson(Class<E> clazz, JSONObject json)
RealmObject
and a field is not found in the JSON object, that field will not be updated. If a new RealmObject is
created and a field is not found in the JSON object, that field will be assigned the default value for the field type.clazz - Type of RealmObject to create or update. It must have a primary key defined.json - JSONObject with object data.RealmObject.IllegalArgumentException - if trying to update a class without a PrimaryKey.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.RealmException - if JSON data cannot be mapped.createObjectFromJson(Class, org.json.JSONObject)public <E extends RealmModel> E createObjectFromJson(Class<E> clazz, String json)
RealmObject field is not present in the JSON
object the RealmObject field will be set to the default value for that type.clazz - type of Realm object to create.json - the JSON string with object data.null if JSON string was empty or null.RealmException - if mapping to json failed.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.public <E extends RealmModel> E createOrUpdateObjectFromJson(Class<E> clazz, String json)
RealmObject and a field is not found in the JSON object, that field will not be updated. If a new
RealmObject is created and a field is not found in the JSON object, that field will be assigned the
default value for the field type.clazz - type of RealmObject to create or update. It must have a primary key defined.json - string with object data in JSON format.RealmObject.IllegalArgumentException - if trying to update a class without a PrimaryKey.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.RealmException - if JSON object cannot be mapped from the string parameter.createObjectFromJson(Class, String)public <E extends RealmModel> E createObjectFromJson(Class<E> clazz, InputStream inputStream) throws IOException
RealmObject field is not present in the JSON
object the RealmObject field will be set to the default value for that type.
This API is only available in API level 11 or later.
clazz - type of Realm object to create.inputStream - the JSON object data as a InputStream.null if JSON string was empty or null.RealmException - if the mapping from JSON failed.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.IOException - if something went wrong with the input stream.public <E extends RealmModel> E createOrUpdateObjectFromJson(Class<E> clazz, InputStream in)
RealmObject and a field is not found in the JSON object, that field will not be updated. If a new
RealmObject is created and a field is not found in the JSON object, that field will be assigned the
default value for the field type.
This API is only available in API level 11 or later.
clazz - type of RealmObject to create or update. It must have a primary key defined.in - the InputStream with object data in JSON format.RealmObject.IllegalArgumentException - if trying to update a class without a PrimaryKey.IllegalArgumentException - if the JSON object doesn't have a primary key property but the corresponding
RealmObjectSchema has a PrimaryKey defined.RealmException - if failure to read JSON.createObjectFromJson(Class, java.io.InputStream)public <E extends RealmModel> E createObject(Class<E> clazz)
This method is only available for model classes with no @PrimaryKey annotation.
If you like to create an object that has a primary key, use createObject(Class, Object)
or copyToRealm(RealmModel) instead.
clazz - the Class of the object to create.RealmException - if the primary key is defined in the model class or an object cannot be created.createObject(Class, Object)public <E extends RealmModel> E createObject(Class<E> clazz, Object primaryKeyValue)
If the value violates the primary key constraint, no object will be added and a RealmException will be
thrown.
The default value for primary key provided by the model class will be ignored.
clazz - the Class of the object to create.primaryKeyValue - value for the primary key field.RealmException - if object could not be created due to the primary key being invalid.IllegalStateException - if the model class does not have an primary key defined.IllegalArgumentException - if the primaryKeyValue doesn't have a value that can be converted to the
expected value.public <E extends RealmModel> E copyToRealm(E object)
Please note, copying an object will copy all field values. Any unset field in this and child objects will be set to their default value if not provided.
object - the RealmObject to copy to the Realm.IllegalArgumentException - if the object is null or it belongs to a Realm instance
in a different thread.public <E extends RealmModel> E copyToRealmOrUpdate(E object)
PrimaryKey or creates
a new copy if no existing object could be found. This is a deep copy or update i.e., all referenced objects will be
either copied or updated.
Please note, copying an object will copy all field values. Any unset field in the object and child objects will be set to their default value if not provided.
object - RealmObject to copy or update.IllegalArgumentException - if the object is null or doesn't have a Primary key defined
or it belongs to a Realm instance in a different thread.copyToRealm(RealmModel)public <E extends RealmModel> List<E> copyToRealm(Iterable<E> objects)
Please note, copying an object will copy all field values. Any unset field in the objects and child objects will be set to their default value if not provided.
objects - the RealmObjects to copy to the Realm.RealmException - if any of the objects has already been added to Realm.IllegalArgumentException - if any of the elements in the input collection is null.public void insert(Collection<? extends RealmModel> objects)
copyToRealm(Iterable) since it
doesn't return the inserted elements, and performs minimum allocations and checks.
After being inserted any changes to the original objects will not be persisted.
Please note:
RealmObject for each element
If you want the managed RealmObject returned, use copyToRealm(Iterable), otherwise if
you have a large number of object this method is generally faster.
objects - RealmObjects to insert.IllegalStateException - if the corresponding Realm is closed, called from an incorrect thread or not in a
transaction.copyToRealm(Iterable)public void insert(RealmModel object)
copyToRealm(RealmModel) since it
doesn't return the inserted elements, and performs minimum allocations and checks.
After being inserted any changes to the original object will not be persisted.
Please note:
RealmObject for each element
If you want the managed RealmObject returned, use copyToRealm(RealmModel), otherwise if
you have a large number of object this method is generally faster.
object - RealmObjects to insert.IllegalStateException - if the corresponding Realm is closed, called from an incorrect thread or not in a
transaction.RealmPrimaryKeyConstraintException - if two objects with the same primary key is
inserted or if a primary key value already exists in the Realm.copyToRealm(RealmModel)public void insertOrUpdate(Collection<? extends RealmModel> objects)
copyToRealmOrUpdate(Iterable) since it doesn't return the inserted elements, and performs minimum
allocations and checks.
After being inserted any changes to the original objects will not be persisted.
Please note:
RealmObject for each element
If you want the managed RealmObject returned, use copyToRealm(Iterable), otherwise if
you have a large number of object this method is generally faster.
objects - RealmObjects to insert.IllegalStateException - if the corresponding Realm is closed, called from an incorrect thread or not in a
transaction.RealmPrimaryKeyConstraintException - if two objects with the same primary key is
inserted or if a primary key value already exists in the Realm.copyToRealmOrUpdate(Iterable)public void insertOrUpdate(RealmModel object)
copyToRealmOrUpdate(RealmModel) since it doesn't return the inserted elements, and performs minimum
allocations and checks.
After being inserted any changes to the original object will not be persisted.
Please note:
RealmObject for each element
If you want the managed RealmObject returned, use copyToRealm(RealmModel), otherwise if
you have a large number of object this method is generally faster.
object - RealmObjects to insert.IllegalStateException - if the corresponding Realm is closed, called from an incorrect thread or not in a
transaction.copyToRealmOrUpdate(RealmModel)public <E extends RealmModel> List<E> copyToRealmOrUpdate(Iterable<E> objects)
PrimaryKey or
creates a new copy if no existing object could be found. This is a deep copy or update i.e., all referenced
objects will be either copied or updated.
Please note, copying an object will copy all field values. Any unset field in the objects and child objects will be set to their default value if not provided.
objects - a list of objects to update or copy into Realm.IllegalArgumentException - if RealmObject is null or doesn't have a Primary key defined.copyToRealm(Iterable)public <E extends RealmModel> List<E> copyFromRealm(Iterable<E> realmObjects)
The copied objects are all detached from Realm and they will no longer be automatically updated. This means that the copied objects might contain data that are no longer consistent with other managed Realm objects.
*WARNING*: Any changes to copied objects can be merged back into Realm using
copyToRealmOrUpdate(RealmModel), but all fields will be overridden, not just those that were changed.
This includes references to other objects, and can potentially override changes made by other threads.
E - type of object.realmObjects - RealmObjects to copy.IllegalArgumentException - if the RealmObject is no longer accessible or it is a DynamicRealmObject.copyToRealmOrUpdate(Iterable)public <E extends RealmModel> List<E> copyFromRealm(Iterable<E> realmObjects, int maxDepth)
The copied objects are all detached from Realm and they will no longer be automatically updated. This means that the copied objects might contain data that are no longer consistent with other managed Realm objects.
*WARNING*: Any changes to copied objects can be merged back into Realm using
copyToRealmOrUpdate(Iterable), but all fields will be overridden, not just those that were changed.
This includes references to other objects even though they might be null due to maxDepth being
reached. This can also potentially override changes made by other threads.
E - type of object.realmObjects - RealmObjects to copy.maxDepth - limit of the deep copy. All references after this depth will be null. Starting depth is
0.IllegalArgumentException - if maxDepth < 0, the RealmObject is no longer accessible or it is a
DynamicRealmObject.copyToRealmOrUpdate(Iterable)public <E extends RealmModel> E copyFromRealm(E realmObject)
RealmObject. This is a deep copy that will copy
all referenced objects.
The copied object(s) are all detached from Realm and they will no longer be automatically updated. This means that the copied objects might contain data that are no longer consistent with other managed Realm objects.
*WARNING*: Any changes to copied objects can be merged back into Realm using
copyToRealmOrUpdate(RealmModel), but all fields will be overridden, not just those that were changed.
This includes references to other objects, and can potentially override changes made by other threads.
E - type of object.realmObject - RealmObject to copy.RealmObject.IllegalArgumentException - if the RealmObject is no longer accessible or it is a DynamicRealmObject.copyToRealmOrUpdate(RealmModel)public <E extends RealmModel> E copyFromRealm(E realmObject, int maxDepth)
RealmObject. This is a deep copy that will copy
all referenced objects up to the defined depth.
The copied object(s) are all detached from Realm and they will no longer be automatically updated. This means that the copied objects might contain data that are no longer consistent with other managed Realm objects.
*WARNING*: Any changes to copied objects can be merged back into Realm using
copyToRealmOrUpdate(RealmModel), but all fields will be overridden, not just those that were changed.
This includes references to other objects even though they might be null due to maxDepth being
reached. This can also potentially override changes made by other threads.
E - type of object.realmObject - RealmObject to copy.maxDepth - limit of the deep copy. All references after this depth will be null. Starting depth is
0.RealmObject.IllegalArgumentException - if maxDepth < 0, the RealmObject is no longer accessible or it is a
DynamicRealmObject.copyToRealmOrUpdate(RealmModel)public <E extends RealmModel> RealmQuery<E> where(Class<E> clazz)
clazz - the class of the object which is to be queried for.RealmQuerypublic void addChangeListener(RealmChangeListener<Realm> listener)
The listeners will be executed when changes are committed by this or another thread.
Realm instances are per thread singletons and cached, so listeners should be
removed manually even if calling close(). Otherwise there is a
risk of memory leaks.
listener - the change listener.IllegalArgumentException - if the change listener is null.IllegalStateException - if you try to register a listener from a non-Looper or IntentService thread.RealmChangeListener,
removeChangeListener(RealmChangeListener),
removeAllChangeListeners()public void removeChangeListener(RealmChangeListener<Realm> listener)
listener - the change listener to be removed.IllegalArgumentException - if the change listener is null.IllegalStateException - if you try to remove a listener from a non-Looper Thread.RealmChangeListenerpublic void removeAllChangeListeners()
IllegalStateException - if you try to remove listeners from a non-Looper Thread.RealmChangeListenerpublic void executeTransaction(Realm.Transaction transaction)
beginTransaction() and commitTransaction() will be
called automatically. If any exception is thrown during the transaction cancelTransaction() will be
called instead of commitTransaction().transaction - the Realm.Transaction to execute.IllegalArgumentException - if the transaction is null.RealmMigrationNeededException - if the latest version contains incompatible schema changes.public RealmAsyncTask executeTransactionAsync(Realm.Transaction transaction)
executeTransaction(Transaction) but runs asynchronously on a worker thread.transaction - Realm.Transaction to execute.RealmAsyncTask representing a cancellable task.IllegalArgumentException - if the transaction is null, or if the Realm is opened from
another thread.public RealmAsyncTask executeTransactionAsync(Realm.Transaction transaction, Realm.Transaction.OnSuccess onSuccess)
executeTransactionAsync(Transaction), but also accepts an OnSuccess callback.transaction - Realm.Transaction to execute.onSuccess - callback invoked when the transaction succeeds.RealmAsyncTask representing a cancellable task.IllegalArgumentException - if the transaction is null, or if the realm is opened from
another thread.public RealmAsyncTask executeTransactionAsync(Realm.Transaction transaction, Realm.Transaction.OnError onError)
executeTransactionAsync(Transaction), but also accepts an OnError callback.transaction - Realm.Transaction to execute.onError - callback invoked when the transaction fails.RealmAsyncTask representing a cancellable task.IllegalArgumentException - if the transaction is null, or if the realm is opened from
another thread.public RealmAsyncTask executeTransactionAsync(Realm.Transaction transaction, Realm.Transaction.OnSuccess onSuccess, Realm.Transaction.OnError onError)
executeTransactionAsync(Transaction), but also accepts an OnSuccess and OnError callbacks.transaction - Realm.Transaction to execute.onSuccess - callback invoked when the transaction succeeds.onError - callback invoked when the transaction fails.RealmAsyncTask representing a cancellable task.IllegalArgumentException - if the transaction is null, or if the realm is opened from
another thread.public void delete(Class<? extends RealmModel> clazz)
clazz - the class which objects should be removed.IllegalStateException - if the corresponding Realm is closed or called from an incorrect thread.public static void migrateRealm(RealmConfiguration configuration) throws FileNotFoundException
configuration - RealmConfigurationFileNotFoundException - if the Realm file doesn't exist.public static void migrateRealm(RealmConfiguration configuration, RealmMigration migration) throws FileNotFoundException
configuration - theRealmConfiguration.migration - the RealmMigration to run on the Realm. This will override any migration set on the
configuration.FileNotFoundException - if the Realm file doesn't exist.public static boolean deleteRealm(RealmConfiguration configuration)
RealmConfiguration from the filesystem.
All Realm instances must be closed before calling this method.configuration - a RealmConfiguration.false if a file could not be deleted. The failing file will be logged.IllegalStateException - if not all realm instances are closed.public static boolean compactRealm(RealmConfiguration configuration)
The file must be closed before this method is called, otherwise false will be returned.
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.
configuration - a RealmConfiguration pointing to a Realm file.true if successful, false if any file operation failed.UnsupportedOperationException - if Realm is synchronized.public static Object getDefaultModule()
null if no default module exists.RealmException - if unable to create an instance of the module.RealmConfiguration.Builder.modules(Object, Object...)public static int getGlobalInstanceCount(RealmConfiguration configuration)
configuration - the RealmConfiguration for the Realm.public static int getLocalInstanceCount(RealmConfiguration configuration)
configuration - the RealmConfiguration for the Realm.public void setAutoRefresh(boolean autoRefresh)
Auto-refresh is a feature that enables automatic update of the current Realm instance and all its derived objects
(RealmResults and RealmObject 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 on a Looper enabled
thread.
autoRefresh - true will turn auto-refresh on, false will turn it off.IllegalStateException - if called from a non-Looper thread.public boolean isAutoRefresh()
public void refresh()
WARNING: Calling this on a thread with async queries will turn those queries into synchronous queries.
In most cases it is better to use RealmChangeListeners to be notified about changes to the
Realm on a given thread than it is to use this method.
IllegalStateException - if attempting to refresh from within a transaction.public boolean isInTransaction()
true if inside a transaction, false otherwise.public void writeCopyTo(File destination)
The destination file cannot already exist.
Note that if this is called from within a transaction it writes the current data, and not the data as it was when the last transaction was committed.
destination - file to save the Realm to.RealmFileException - if an error happened when accessing the underlying Realm file or writing to the
destination file.public void writeEncryptedCopyTo(File destination, byte[] key)
The destination file cannot already exist.
Note that if this is called from within a transaction it writes the current data, and not the data as it was when the last transaction was committed.
destination - file to save the Realm to.key - a 64-byte encryption key.IllegalArgumentException - if destination argument is null.RealmFileException - if an error happened when accessing the underlying Realm file or writing to the
destination file.public boolean waitForChange()
stopWaitForChange()
is called from another thread. Once stopWaitForChange is called, all future calls to this method will
return false immediately.true if the Realm was updated to the latest version, false if it was
cancelled by calling stopWaitForChange.IllegalStateException - if calling this from within a transaction or from a Looper thread.RealmMigrationNeededException - on typed Realm if the latest version contains
incompatible schema changes.public void stopWaitForChange()
waitForChange() return false immediately. Once this is called,
all future calls to waitForChange will immediately return false.
This method is thread-safe and should _only_ be called from another thread than the one that called waitForChange.
IllegalStateException - if the Realm instance has already been closed.public void beginTransaction()
BaseRealm.commitTransaction() or aborted by
BaseRealm.cancelTransaction(). Transactions are used to atomically create, update and delete objects
within a Realm.
Before beginning a transaction, the Realm instance is updated to the latest version in order to include all
changes from other threads. This update does not trigger any registered RealmChangeListener.
It is therefore recommended to query for the items that should be modified from inside the transaction. Otherwise there is a risk that some of the results have been deleted or modified when the transaction begins.
// Don't do this
RealmResults<Person> persons = realm.where(Person.class).findAll();
realm.beginTransaction();
persons.first().setName("John");
realm.commitTransaction();
// Do this instead
realm.beginTransaction();
RealmResults<Person> persons = realm.where(Person.class).findAll();
persons.first().setName("John");
realm.commitTransaction();
Notice: it is not possible to nest transactions. If you start a transaction within a transaction an exception is thrown.
RealmMigrationNeededException - on typed Realm if the latest version contains
incompatible schema changes.public void commitTransaction()
BaseRealm.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 update their objects and RealmResults to reflect the
changes from this commit.public void cancelTransaction()
The Realm reverts back to read-only.
Calling this when not in a transaction will throw an exception.
public String getPath()
File.getCanonicalPath()public RealmConfiguration getConfiguration()
RealmConfiguration for this Realm.RealmConfiguration for this Realm.public long getVersion()
public void close()
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.
close in interface Closeableclose in interface AutoCloseableIllegalStateException - if attempting to close from another thread.public boolean isClosed()
Realm instance has already been closed.true if closed, false otherwise.IllegalStateException - if attempting to close from another thread.public boolean isEmpty()
Realm contains any objects.true if empty, @{code false} otherwise.public RealmSchema getSchema()
RealmSchema for this Realm.public void deleteAll()
IllegalStateException - if the corresponding Realm is closed or called from an incorrect thread.