DynamicRealm (Realm 4.2.0)

java.lang.Object
- io.realm.DynamicRealm

All Implemented Interfaces:

Closeable, AutoCloseable
```
public class DynamicRealm
extends Object
```
DynamicRealm is a dynamic variant of Realm. This means that all access to data and/or queries are done using string based class names instead of class type references.
This is useful during migrations or when working with string-based data like CSV or XML files.
The same RealmConfiguration can be used to open a Realm file in both dynamic and typed mode, but modifying the schema while having both a typed and dynamic version open is highly discouraged and will most likely crash the typed Realm. During migrations only a DynamicRealm will be open.
Dynamic Realms do not enforce schemas or schema versions and RealmMigration code is not used even if it has been defined in the RealmConfiguration.
This means that the schema is not created or validated until a Realm has been opened in typed mode. If a Realm file is opened in dynamic mode first it will not contain any information about classes and fields, and any queries for classes defined by the schema will fail.

See Also:

Realm, RealmSchema

Nested Class Summary

Nested Classes
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 `Realm.getInstanceAsync(RealmConfiguration, Realm.Callback)` or `getInstanceAsync(RealmConfiguration, DynamicRealm.Callback)`.
`static class`	`io.realm.BaseRealm.RealmObjectContext`
`static class`	`DynamicRealm.Callback` The Callback used when reporting back the result of loading a Realm asynchronously using either `Realm.getInstanceAsync(RealmConfiguration, Realm.Callback)` or `getInstanceAsync(RealmConfiguration, DynamicRealm.Callback)`.
`static interface`	`DynamicRealm.Transaction` Encapsulates a Realm transaction.

Field Summary

Fields
Modifier and Type Field and Description

static io.realm.BaseRealm.ThreadLocalRealmObjectContext objectContext

OsSharedRealm sharedRealm

Fields
Modifier and Type	Field and Description
`static io.realm.BaseRealm.ThreadLocalRealmObjectContext`	`objectContext`
`OsSharedRealm`	`sharedRealm`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addChangeListener(RealmChangeListener<DynamicRealm> listener)` Adds a change listener to the Realm.
`<any>`	`asFlowable()` Returns an RxJava Flowable 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.
`DynamicRealmObject`	`createObject(String className)` Instantiates and adds a new object to the Realm.
`DynamicRealmObject`	`createObject(String className, Object primaryKeyValue)` Creates an object with a given primary key.
`void`	`delete(String className)` Deletes all objects of the specified class from the Realm.
`void`	`deleteAll()` Deletes all objects from this Realm.
`void`	`executeTransaction(DynamicRealm.Transaction transaction)` Executes a given transaction on the DynamicRealm.
`RealmConfiguration`	`getConfiguration()` Returns the `RealmConfiguration` for this Realm.
`static DynamicRealm`	`getInstance(RealmConfiguration configuration)` Realm static constructor that returns a dynamic variant of the Realm instance defined by provided `RealmConfiguration`.
`static RealmAsyncTask`	`getInstanceAsync(RealmConfiguration configuration, DynamicRealm.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).
`String`	`getPath()` Returns the canonical path to where this Realm is persisted on disk.
`RealmSchema`	`getSchema()` Returns the mutable schema for this Realm.
`long`	`getVersion()` Returns the schema version for this Realm.
`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.
`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<DynamicRealm> listener)` Removes the specified change listener.
`void`	`setAutoRefresh(boolean autoRefresh)` Sets the auto-refresh status of the Realm instance.
`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.
`RealmQuery<DynamicRealmObject>`	`where(String className)` Returns a RealmQuery, which can be used to query the provided class.
`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.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - sharedRealm
```
public OsSharedRealm sharedRealm
```
  - objectContext
```
public static final io.realm.BaseRealm.ThreadLocalRealmObjectContext objectContext
```
- Method Detail
  - getInstance
```
public static DynamicRealm getInstance(RealmConfiguration configuration)
```
    Realm static constructor that returns a dynamic variant of the Realm instance defined by provided RealmConfiguration. Dynamic Realms do not care about schemaVersion and schemas, so opening a DynamicRealm will never trigger a migration.
    
    Returns:
    
    the DynamicRealm defined by the configuration.
    
    Throws:
    
    RealmFileException - if an error happened when accessing the underlying Realm file.
    
    IllegalArgumentException - if configuration argument is null.
    
    See Also:
    
    for details on how to configure a Realm.
  - getInstanceAsync
```
public static RealmAsyncTask getInstanceAsync(RealmConfiguration configuration,
                                              DynamicRealm.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). 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.
    
    Parameters:
    
    configuration - RealmConfiguration used to open the Realm.
    
    callback - invoked to return the results.
    
    Returns:
    
    a RealmAsyncTask representing a cancellable task.
    
    Throws:
    
    IllegalArgumentException - if a null RealmConfiguration or a null DynamicRealm.Callback is provided.
    
    IllegalStateException - if it is called from a non-Looper or IntentService thread.
    
    See Also:
    
    for more details.
  - createObject
```
public DynamicRealmObject createObject(String className)
```
    Instantiates and adds a new object to the Realm.
    
    Parameters:
    
    className - the class name of the object to create.
    
    Returns:
    
    the new object.
    
    Throws:
    
    RealmException - if the object could not be created.
  - createObject
```
public DynamicRealmObject createObject(String className,
                                       Object primaryKeyValue)
```
    Creates an object with a given primary key. Classes without a primary key defined must use createObject(String)} instead.
    
    Returns:
    
    the new object. All fields will have default values for their type, except for the primary key field which will have the provided value.
    
    Throws:
    
    RealmException - if object could not be created due to the primary key being invalid.
    
    IllegalStateException - if the model clazz does not have an primary key defined.
    
    IllegalArgumentException - if the primaryKeyValue doesn't have a value that can be converted to the expected value.
  - where
```
public RealmQuery<DynamicRealmObject> where(String className)
```
    Returns a RealmQuery, which can be used to query the provided class.
    
    Parameters:
    
    className - the class of the object which is to be queried.
    
    Returns:
    
    a RealmQuery, which can be used to query for specific objects of provided type.
    
    Throws:
    
    IllegalArgumentException - if the class doesn't exist.
    
    See Also:
    
    RealmQuery
  - addChangeListener
```
public void addChangeListener(RealmChangeListener<DynamicRealm> listener)
```
    Adds a change listener to the Realm.
    The listeners will be executed when changes are committed by this or another thread.
    Realm instances are cached per thread. For that reason it is important to remember to remove listeners again either using removeChangeListener(RealmChangeListener) or removeAllChangeListeners(). Not doing so can cause memory leaks.
    
    Parameters:
    
    listener - the change listener.
    
    Throws:
    
    IllegalArgumentException - if the change listener is null.
    
    See Also:
    
    RealmChangeListener, removeChangeListener(RealmChangeListener), removeAllChangeListeners(), waitForChange()
  - removeChangeListener
```
public void removeChangeListener(RealmChangeListener<DynamicRealm> listener)
```
    Removes the specified change listener.
    
    Parameters:
    
    listener - the change listener to be removed.
    
    Throws:
    
    IllegalArgumentException - if the change listener is null.
    
    IllegalStateException - if you try to remove a listener from a non-Looper Thread.
    
    See Also:
    
    RealmChangeListener
  - removeAllChangeListeners
```
public void removeAllChangeListeners()
```
    Removes all user-defined change listeners.
    
    Throws:
    
    IllegalStateException - if you try to remove listeners from a non-Looper Thread.
    
    See Also:
    
    RealmChangeListener
  - delete
```
public void delete(String className)
```
    Deletes all objects of the specified class from the Realm.
    
    Parameters:
    
    className - the class for which all objects should be removed.
  - executeTransaction
```
public void executeTransaction(DynamicRealm.Transaction transaction)
```
    Executes a given transaction on the DynamicRealm. beginTransaction() and commitTransaction() will be called automatically. If any exception is thrown during the transaction cancelTransaction() will be called instead of commitTransaction().
    
    Parameters:
    
    transaction - DynamicRealm.Transaction to execute.
    
    Throws:
    
    IllegalArgumentException - if the transaction is null.
  - asFlowable
```
public <any> asFlowable()
```
    Returns an RxJava Flowable that monitors changes to this Realm. It will emit the current state when subscribed to. Items will continually be emitted as the Realm is updated - onComplete will never be called.
    If you would like the asFlowable() to stop emitting items, you can instruct RxJava to only emit only the first item by using the first() operator:
```
 
 realm.asFlowable().first().subscribe( ... ) // You only get the results once
 
 
```
    Returns:
    
    RxJava Observable that only calls onNext. It will never call onComplete or OnError.
    
    See Also:
    
    RxJava and Realm
  - getSchema
```
public RealmSchema getSchema()
```
    Returns the mutable schema for this Realm.
    
    Returns:
    
    The RealmSchema for this Realm.
  - setAutoRefresh
```
public void setAutoRefresh(boolean autoRefresh)
```
    Sets 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 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.
    
    Parameters:
    
    autoRefresh - true will turn auto-refresh on, false will turn it off.
    
    Throws:
    
    IllegalStateException - if called from a non-Looper thread.
  - isAutoRefresh
```
public boolean isAutoRefresh()
```
    Retrieves the auto-refresh status of the Realm instance.
    
    Returns:
    
    the auto-refresh status.
  - refresh
```
public void refresh()
```
    Refreshes the Realm instance and all the RealmResults and RealmObjects instances coming from it. It also calls any listeners associated with the Realm if neeeded.
    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.
    
    Throws:
    
    IllegalStateException - if attempting to refresh from within a transaction.
  - isInTransaction
```
public boolean isInTransaction()
```
    Checks if the Realm is currently in a transaction.
    
    Returns:
    
    true if inside a transaction, false otherwise.
  - writeCopyTo
```
public void writeCopyTo(File destination)
```
    Writes 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 transaction it writes the current data, and not the data as it was when the last transaction was committed.
    
    Parameters:
    
    destination - file to save the Realm to.
    
    Throws:
    
    RealmFileException - if an error happened when accessing the underlying Realm file or writing to the destination file.
  - writeEncryptedCopyTo
```
public void writeEncryptedCopyTo(File destination,
                                 byte[] key)
```
    Writes 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 transaction it writes the current data, and not the data as it was when the last transaction was committed.
    
    Parameters:
    
    destination - file to save the Realm to.
    
    key - a 64-byte encryption key.
    
    Throws:
    
    IllegalArgumentException - if destination argument is null.
    
    RealmFileException - if an error happened when accessing the underlying Realm file or writing to the destination file.
  - waitForChange
```
public boolean waitForChange()
```
    Blocks the current thread until new changes to the Realm are available or stopWaitForChange() is called from another thread. Once stopWaitForChange is called, all future calls to this method will return false immediately.
    
    Returns:
    
    true if the Realm was updated to the latest version, false if it was cancelled by calling stopWaitForChange.
    
    Throws:
    
    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.
  - stopWaitForChange
```
public void stopWaitForChange()
```
    Makes any current 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.
    
    Throws:
    
    IllegalStateException - if the Realm instance has already been closed.
  - beginTransaction
```
public void beginTransaction()
```
    Starts a transaction which must be closed by 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.
    Throws:
    
    RealmMigrationNeededException - on typed Realm if the latest version contains incompatible schema changes.
  - commitTransaction
```
public void commitTransaction()
```
    All changes since 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.
  - cancelTransaction
```
public void cancelTransaction()
```
    Reverts 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 transaction will throw an exception.
  - getPath
```
public String getPath()
```
    Returns the canonical path to where this Realm is persisted on disk.
    
    Returns:
    
    the canonical path to the Realm file.
    
    See Also:
    
    File.getCanonicalPath()
  - getConfiguration
```
public RealmConfiguration getConfiguration()
```
    Returns the RealmConfiguration for this Realm.
    
    Returns:
    
    the RealmConfiguration for this Realm.
  - getVersion
```
public long getVersion()
```
    Returns the schema version for this Realm.
    
    Returns:
    
    the schema version for the Realm file backing this Realm.
  - 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 Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Throws:
    
    IllegalStateException - if attempting to close from another thread.
  - isClosed
```
public boolean isClosed()
```
    Checks if the Realm instance has already been closed.
    
    Returns:
    
    true if closed, false otherwise.
    
    Throws:
    
    IllegalStateException - if attempting to close from another thread.
  - isEmpty
```
public boolean isEmpty()
```
    Checks if this Realm contains any objects.
    
    Returns:
    
    true if empty, @{code false} otherwise.
  - deleteAll
```
public void deleteAll()
```
    Deletes all objects from this Realm.
    
    Throws:
    
    IllegalStateException - if the corresponding Realm is closed or called from an incorrect thread.

Class DynamicRealm

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

sharedRealm

objectContext

Method Detail

getInstance

getInstanceAsync

createObject

createObject

where

addChangeListener

removeChangeListener

removeAllChangeListeners

delete

executeTransaction

asFlowable

getSchema

setAutoRefresh

isAutoRefresh

refresh

isInTransaction

writeCopyTo

writeEncryptedCopyTo

waitForChange

stopWaitForChange

beginTransaction

commitTransaction

cancelTransaction

getPath

getConfiguration

getVersion

close

isClosed

isEmpty

deleteAll