// Define you model class by extending RealmObject
public class Dog extends RealmObject {
    private String name;
    private int age;

    // ... Generated getters and setters ...
}

public class Person extends RealmObject {
    @PrimaryKey
    private long id;
    private String name;
    private RealmList<Dog> dogs; // Declare one-to-many relationships

    public Person(long id, String name) {
        this.id = id;
        this.name = name;
    }

    // ... Generated getters and setters ...
}

// Use them like regular java objects
Dog dog = new Dog();
dog.setName("Rex");
dog.setAge(1);

// Initialize Realm
Realm.init(context);

// Get a Realm instance for this thread
Realm realm = Realm.getDefaultInstance();

// Query Realm for all dogs younger than 2 years old
final RealmResults<Dog> puppies = realm.where(Dog.class).lessThan("age", 2).findAll();
puppies.size(); // => 0 because no dogs have been added to the Realm yet

// Persist your data in a transaction
realm.beginTransaction();
final managedDog = realm.copyToRealm(dog); // Persist unmanaged objects
Person person = realm.createObject(Person); // Create managed objects directly
person.getDogs().add(managedDog);
realm.commitTransaction();

// Listeners will be notified when data changes
puppies.addChangeListener(new RealmChangeListener<RealmResults<Dog>>() {
    @Override
    public void onChange(RealmResults<Dog> results) {
        // Query results are updated in real time
        puppies.size(); // => 1
    }
});

// Asynchronously update objects on a background thread
realm.executeTransactionAsync(new Realm.Transaction() {
    @Override
    public void execute(Realm bgRealm) {
        Dog dog = bgRealm.where(Dog.class).equals("age", 1).findFirst();
        dog.setAge(3);
    }
}, new Realm.Transaction.OnSuccess() {
    @Override
    public void onSuccess() {
    	// Original queries and Realm objects are automatically updated.
    	puppies.size(); // => 0 because there are no more puppies younger than 2 years old
    	managedDog.getAge();   // => 3 the dogs age is updated
    }
});

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath "io.realm:realm-gradle-plugin:2.1.1"
    }
}

apply plugin: 'realm-android'

public class User extends RealmObject {

    private String          name;
    private int             age;

    @Ignore
    private int             sessionId;

    // Standard getters & setters generated by your IDE…
    public String getName() { return name; }
    public void   setName(String name) { this.name = name; }
    public int    getAge() { return age; }
    public void   setAge(int age) { this.age = age; }
    public int    getSessionId() { return sessionId; }
    public void   setSessionId(int sessionId) { this.sessionId = sessionId; }
}

public class User extends RealmObject {

    public String name;

    public boolean hasLongName() {
      return name.length() > 7;
    }

    @Override
    public boolean equals(Object o) {
      // Custom equals comparison
    }
}

final Dog myDog;
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        myDog = realm.createObject(Dog.class);
        myDog.setName("Fido");
        myDog.setAge(1);
    }
});

realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        Dog myPuppy = realm.where(Dog.class).equalTo("age", 1).findFirst();
        myPuppy.setAge(2);
    }
});

myDog.getAge(); // => 2

final MyObject obj = new MyObject();
obj.setId(42);
obj.setName("Fish");
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        // This will create a new object in Realm or throw an exception if the
        // object already exists (same primary key)
        // realm.copyToRealm(obj);

        // This will update an existing object with the same primary key
        // or create a new object if an object with no primary key = 42
        realm.copyToRealmOrUpdate(obj);
    }
});

public class Dog extends RealmObject {
    public String name;
    public int age;
}

realm.executeTransaction(new Realm.Transaction() {
    @Overrride
    public void execute(Realm realm) {
        Dog dog = realm.createObject(Dog.class);
        dog.name = "Fido";
        dog.age  = 5;
    }
};

@RealmClass
public class User implements RealmModel {

}

// With RealmObject
user.isValid();
user.addChangeListener(listener);

// With RealmModel
RealmObject.isValid(user);
RealmObject.addChangeListener(user, listener);

public class Email extends RealmObject {
    private String address;
    private boolean active;
    // ... setters and getters left out
}

public class Contact extends RealmObject {
    private String name;
    private Email email;
    // ... setters and getters left out
}

public class Contact extends RealmObject {
    private Email email;
    // Other fields…
}

public class Contact extends RealmObject {
    public String name;
    public RealmList<Email> emails;
}

public class Email extends RealmObject {
    public String address;
    public boolean active;
}

realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        Contact contact = realm.createObject(Contact.class);
        contact.name = "John Doe";

        Email email1 = realm.createObject(Email.class);
        email1.address = "john@example.com";
        email1.active = true;
        contact.emails.add(email1);

        Email email2 = realm.createObject(Email.class);
        email2.address = "jd@example.com";
        email2.active = false;
        contact.emails.add(email2);
    }
});

public class Person extends RealmObject {
    public String name;
    public RealmList<Person> friends;
    // Other fields…
}

public class Person extends RealmObject {
  private String id;
  private String name;
  private RealmList<Dog> dogs;
  // getters and setters
}

public class Dog extends RealmObject {
  private String id;
  private String name;
  private String color;
  // getters and setters
}

// persons => [U1,U2]
RealmResults<Person> persons = realm.where(Person.class)
                                .equalTo("dogs.color", "Brown")
                                .findAll();

persons.get(0).getDogs(); // => [A,B]
persons.get(1).getDogs(); // => [B,C,D]

// r1 => [U1,U2]
RealmResults<Person> r1 = realm.where(Person.class)
                             .equalTo("dogs.name", "Fluffy")
                             .findAll();

// r2 => [U1,U2]
RealmResults<Person> r2 = r1.where()
                          .equalTo("dogs.color", "Brown")
                          .findAll();

// r1 => [u1,u2]
realmresults<user> r1 = realm.where(user.class)
                             .equalto("dogs.name", "fluffy")
                             .equalto("dogs.color", "brown")
                             .findall();

// r2 => [u2]
realmresults<user> r2 = realm.where(user.class)
                             .equalto("dogs.name", "fluffy")
                             .findall()
                             .where()
                             .equalto("dogs.color", "brown")
                             .findall();
                             .where()
                             .equalto("dogs.color", "yellow")
                             .findall();

// Obtain a Realm instance
Realm realm = Realm.getDefaultInstance();

realm.beginTransaction();

//... add or update objects here ...

realm.commitTransaction();

realm.beginTransaction();
User user = realm.createObject(User.class);

//  ...

realm.cancelTransaction();

realm.beginTransaction();
User user = realm.createObject(User.class); // Create a new object
user.setName("John");
user.setEmail("john@corporation.com");
realm.commitTransaction();

User user = new User("John");
user.setEmail("john@corporation.com");

// Copy the object to Realm. Any further changes must happen on realmUser
realm.beginTransaction();
User realmUser = realm.copyToRealm(user);
realm.commitTransaction();

realm.executeTransaction(new Realm.Transaction() {
	@Override
	public void execute(Realm realm) {
		User user = realm.createObject(User.class);
		user.setName("John");
		user.setEmail("john@corporation.com");
	}
});

realm.executeTransactionAsync(new Realm.Transaction() {
    @Override
    public void execute(Realm bgRealm) {
        User user = bgRealm.createObject(User.class);
        user.setName("John");
        user.setEmail("john@corporation.com");
    }
}, new Realm.Transaction.OnSuccess() {
    @Override
    public void onSuccess() {
        // Transaction was a success.
    }
}, new Realm.Transaction.OnError() {
    @Override
    public void onError(Throwable error) {
        // Transaction failed and was automatically canceled.
    }
});

RealmAsyncTask transaction = realm.executeTransactionAsync(new Realm.Transaction() {
            @Override
            public void execute(Realm bgRealm) {
                User user = bgRealm.createObject(User.class);
                user.setName("John");
                user.setEmail("john@corporation.com");
            }
        }, null);

public void onStop () {
    if (transaction != null && !transaction.isCancelled()) {
        transaction.cancel();
    }
}

realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        bytes[] bytes = realmObject.binary;
        bytes[4] = 'a';
        realm.binary = bytes;
    }
});

public class User extends RealmObject {

    @PrimaryKey
    private String          name;
    private int             age;

    @Ignore
    private int             sessionId;

    // Standard getters & setters generated by your IDE…
    public String getName() { return name; }
    public void   setName(String name) { this.name = name; }
    public int    getAge() { return age; }
    public void   setAge(int age) { this.age = age; }
    public int    getSessionId() { return sessionId; }
    public void   setSessionId(int sessionId) { this.sessionId = sessionId; }
}

// Build the query looking at all users:
RealmQuery<User> query = realm.where(User.class);

// Add query conditions:
query.equalTo("name", "John");
query.or().equalTo("name", "Peter");

// Execute the query:
RealmResults<User> result1 = query.findAll();

// Or alternatively do the same all at once (the "Fluent interface"):
RealmResults<User> result2 = realm.where(User.class)
                                  .equalTo("name", "John")
                                  .or()
                                  .equalTo("name", "Peter")
                                  .findAll();

public class User extends RealmObject {

    @PrimaryKey
    private String          name;
    private int             age;

    @Ignore
    private int             sessionId;

    // Standard getters & setters generated by your IDE…
    public String getName() { return name; }
    public void   setName(String name) { this.name = name; }
    public int    getAge() { return age; }
    public void   setAge(int age) { this.age = age; }
    public int    getSessionId() { return sessionId; }
    public void   setSessionId(int sessionId) { this.sessionId = sessionId; }
}

RealmResults<User> r = realm.where(User.class)
                            .greaterThan("age", 10)  //implicit AND
                            .beginGroup()
                                .equalTo("name", "Peter")
                                .or()
                                .contains("name", "Jo")
                            .endGroup()
                            .findAll();

RealmResults<User> result = realm.where(User.class).findAll();
result = result.sort("age"); // Sort ascending
result = result.sort("age", Sort.DESCENDING);

RealmResults<Person> teenagers = realm.where(Person.class).between("age", 13, 20).findAll();
Person firstJohn = teenagers.where().equalTo("name", "John").findFirst();

public class Dog extends RealmObject {
    private int age;
    // getters & setters ...
}

public class Person extends RealmObject {
    private int age;
    private RealmList<Dog> dogs;
    // getters & setters ...
}

RealmResults<Person> teensWithPups = realm.where(Person.class).between("age", 13, 20).equalTo("dogs.age", 1).findAll();

final RealmResults<Dog> puppies = realm.where(Dog.class).lessThan("age", 2).findAll();
puppies.size(); // => 0

realm.executeTransaction(new Realm.Transaction() {
    @Override
    void public execute(Realm realm) {
        Dog dog = realm.createObject(Dog.class);
        dog.setName("Fido");
        dog.setAge(1);
    }
});

puppies.addChangeListener(new RealmChangeListener() {
    @Override
    public void onChange(RealmResults<Dog> results) {
      // results and puppies point are both up to date
      results.size(); // => 1
      puppies.size(); // => 1
    }
});

RealmResults<User> results = realm.where(User.class).findAll();
long   sum     = results.sum("age").longValue();
long   min     = results.min("age").longValue();
long   max     = results.max("age").longValue();
double average = results.average("age");
long   matches = results.size();

RealmResults<User> results = realm.where(User.class).findAll();
for (User u : results) {
    // ... do something with the object ...
}

RealmResults<User> results = realm.where(User.class).findAll();
for (int i = 0; i < results.size(); i++) {
    User u = results.get(i);
    // ... do something with the object ...
}

final RealmResults<User> users = getUsers();
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        users.get(0).deleteFromRealm(); // indirectly delete object
    }
});

for (User user : users) {
    showUser(user); // Will crash for the deleted user
}

final RealmResults<User> users = getUsers();
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        users.deleteFromRealm(0); // Delete and remove object directly
    }
});

for (User user : users) {
    showUser(user); // Deleted user will not be shown
}

// obtain the results of a query
final RealmResults<Dog> results = realm.where(Dog.class).findAll();

// All changes to data must happen in a transaction
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        // remove single match
        results.deleteFirstFromRealm();
        results.deleteLastFromRealm();

        // remove a single object
        Dog dog = results.get(5);
        dog.deleteFromRealm();

        // Delete all matches
        results.deleteAllFromRealm();
    }
});

RealmResults<User> result = realm.where(User.class)
                              .equalTo("name", "John")
                              .or()
                              .equalTo("name", "Peter")
                              .findAllAsync();

private RealmChangeListener callback = new RealmChangeListener<RealmResults<User>>() {
    @Override
    public void onChange(RealmResults<User> results) {
        // called once the query complete and on every update
    }
};

public void onStart() {
    RealmResults<User> result = realm.where(User.class).findAllAsync();
    result.addChangeListener(callback);
}

public void onStop () {
    result.removeChangeListener(callback); // remove a particular listener
    // or
    result.removeChangeListeners(); // remove all registered listeners
}

RealmResults<User> result = realm.where(User.class).findAllAsync();
if (result.isLoaded()) {
  // Results are now available
}

RealmResults<User> result = realm.where(User.class).findAllAsync();
result.load() // be careful, this will block the current thread until it returns

Realm.init(context);

public class MyApplication extends Application {
  @Override
  public void onCreate() {
    super.onCreate();
    Realm.init(this);
  }
}

<application
  android:name=".MyApplication"
  ...
/>

RealmConfiguration config = new RealmConfiguration.Builder().build();

// The RealmConfiguration is created using the builder pattern.
// The Realm file will be located in Context.getFilesDir() with name "myrealm.realm"
RealmConfiguration config = new RealmConfiguration.Builder()
  .name("myrealm.realm")
  .encryptionKey(getKey())
  .schemaVersion(42)
  .modules(new MySchemaModule())
  .migration(new MyMigration())
  .build();
// Use the config
Realm realm = Realm.getInstance(config);

RealmConfiguration myConfig = new RealmConfiguration.Builder()
  .name("myrealm.realm")
  .schemaVersion(2)
  .modules(new MyCustomSchema())
  .build();

RealmConfiguration otherConfig = new RealmConfiguration.Builder()
  .name("otherrealm.realm")
  .schemaVersion(5)
  .modules(new MyOtherSchema())
  .build();

Realm myRealm = Realm.getInstance(myConfig);
Realm otherRealm = Realm.getInstance(otherConfig);

public class MyApplication extends Application {
  @Override
  public void onCreate() {
    super.onCreate();
    // The Realm file will be located in Context.getFilesDir() with name "default.realm"
    RealmConfiguration config = new RealmConfiguration.Builder().build();
    Realm.setDefaultConfiguration(config);
  }
}

public class MyActivity extends Activity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Realm realm = Realm.getDefaultInstance();
    // ... Do something ...
    realm.close();
  }
}

RealmConfiguration myConfig = new RealmConfiguration.Builder()
    .name("myrealm.realm")
    .inMemory()
    .build();

RealmConfiguration realmConfig = new RealmConfiguration.Builder().build();
DynamicRealm realm = DynamicRealm.getInstance(realmConfig);

// In a DynamicRealm all objects are DynamicRealmObjects
DynamicRealmObject person = realm.createObject("Person");

// All fields are accessed using strings
String name = person.getString("name");
int age = person.getInt("age");

// An underlying schema still exists, so accessing a field that does not exist
// will throw an exception
person.getString("I don't exist");

// Queries still work normally
RealmResults<DynamicRealmObject> persons = realm.where("Person")
    .equalTo("name", "John")
    .findAll();

public class MyThread extends Thread {

    private Realm realm;

    public void run() {
        Looper.prepare();
        try {
            realm = Realm.getDefaultInstance();
            //... Setup the handlers using the Realm instance ...
            Lopper.loop();
        } finally {
            if (realm != null) {
                realm.close();
            }
        }
    }
}

protected Void doInBackground(Void... params) {
    Realm realm = Realm.getDefaultInstance();
    try {
        // ... Use the Realm instance ...
    } finally {
        realm.close();
    }

    return null;
}

// Run a non-Looper thread with a Realm instance.
Thread thread = new Thread(new Runnable() {
    @Override
    public void run() {
        Realm realm = null;
        try {
            realm = Realm.getDefaultInstance();
            // ... Use the Realm instance ...
        } finally {
            if (realm != null) {
                realm.close();
            }
        }
    }
});

thread.start();

try (Realm realm = Realm.getDefaultInstance()) {
    // No need to close the Realm instance manually
}

// in a Fragment or Activity, etc
@Override
public void onActivityCreated(Bundle savedInstanceState) {
    // ... boilerplate omitted for brevity
    realm = Realm.getDefaultInstance();
    // get all the customers
    RealmResults<Customer> customers = realm.where(Customer.class).findAllAsync();
    // ... build a list adapter and set it to the ListView/RecyclerView/etc

    // set up a Realm change listener
    changeListener = new RealmChangeListener<RealmResults<Customer>>() {
        @Override
        public void onChange(RealmResults<Customer> results) {
            // This is called anytime the Realm database changes on any thread.
            // Please note, change listeners only work on Looper threads.
            // For non-looper threads, you manually have to use Realm.waitForChange() instead.
            listAdapter.notifyDataSetChanged(); // Update the UI
        }
    };
    // Tell Realm to notify our listener when the customers results
    // have changed (items added, removed, updated, anything of the sort).
    customers.addChangeListener(changeListener);
}

// In a background service, in another thread
public class PollingService extends IntentService {
    @Override
    public void onHandleIntent(Intent intent) {
        Realm realm = Realm.getDefaultInstance();
        // go do some network calls/etc and get some data and stuff it into a 'json' var
        String json = customerApi.getCustomers();
        realm.beginTransaction();
        realm.createObjectFromJson(Customer.class, json); // Save a bunch of new Customer objects
        realm.commitTransaction();
        // At this point, the data in the UI thread is already up to date.
        // ...
    }
    // ...
}

// Create the module
@RealmModule(classes = { Person.class, Dog.class })
public class MyModule {
}

// Set the module in the RealmConfiguration to allow only classes defined by the module.
RealmConfiguration config = new RealmConfiguration.Builder()
  .modules(new MyModule())
  .build();

// It is possible to combine multiple modules to one schema.
RealmConfiguration config = new RealmConfiguration.Builder()
  .modules(new MyModule(), new MyOtherModule())
  .build();

// Library must create a module and set library = true. This will prevent the default
// module from being created.
// allClasses = true can be used instead of listing all classes in the library.
@RealmModule(library = true, allClasses = true)
public class MyLibraryModule {
}

// Library projects are therefore required to explicitly set their own module.
RealmConfiguration libraryConfig = new RealmConfiguration.Builder()
  .name("library.realm")
  .modules(new MyLibraryModule())
  .build();

// Apps can add the library RealmModule to their own schema.
RealmConfiguration config = new RealmConfiguration.Builder()
  .name("app.realm")
  .modules(Realm.getDefaultModule(), new MyLibraryModule())
  .build();

// A RealmObject that represents a city
public class City extends RealmObject {
    private String city;
    private int id;
    // getters and setters left out ...
}

// Insert from a string
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        realm.createObjectFromJson(City.class, "{ city: \"Copenhagen\", id: 1 }");
    }
});

// Insert multiple items using an InputStream
realm.executeTransaction(new Realm.Transaction() {
    @Override
    public void execute(Realm realm) {
        try {
            InputStream is = new FileInputStream(new File("path_to_file"));
            realm.createAllFromJson(City.class, is);
        } catch (IOException e) {
            throw new RuntimeException();
        }
    }
});

public class MyActivity extends Activity {
    private Realm realm;
    private RealmChangeListener realmListener;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      realm = Realm.getDefaultInstance();
      reamlListener = new RealmChangeListener<Realm>() {
        @Override
        public void onChange(Realm realm) {
            // ... do something with the updates (UI, etc.) ...
        }};
      realm.addChangeListener(realmListener);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        // Remove the listener.
        realm.removeChangeListener(realmListener);
        // Close the Realm instance.
        realm.close();
    }
}

realm.removeAllChangeListeners();

public class MyActivity extends Activity {
    private Realm realm;
    private RealmChangeListener puppiesListener;
    private RealmChangeListener dogListener;

    private RealmResults<Dog> puppies;
    private Dog dog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      realm = Realm.getDefaultInstance();
      puppiesListener = new RealmChangeListener<RealmResults<Dog>>() {
        @Override
        public void onChange(RealmResults<Dog> puppies) {
            // ... do something with the updated puppies instance
        }};

      // Find all the puppies
      puppies = realm.where(Dog.class).lessThanOrEqualTo("age", 2).findAll();
      puppies.addChangeListener(puppiesListener);

      dogListener = new RealmChangeListener<Dog>() {
        @Override
        public void onChange(Dog dog) {
            // ... do something with the updated Dog instance
        }};

      dog = realm.where(Dog.class).equals("name", "Fido").findFirst();
      dog.addChangeListener(dogListener);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        // Remove the listeners
        puppies.removeChangeListener(puppiesListener);
        dog.removeChangeListener(dogListener);
        // Close the Realm instance.
        realm.close();
    }
}

Person person = realm.where(Person.class).findFirst();
person.getDogs(); // => 2 - Assume there are 2 dogs in the list
person.addChangeListener(new RealmChangeListener<Person>() {
                             @Override
                             public void onChange(Person person) {
                                 // React to the change in the Person instance.
                                 // This will also get called when any referenced dogs are updated.
                             }
                         });
Dog dog = person.getDogs().get(0);
realm.beginTransaction();
dog.setAge(5);
realm.commitTransaction();
// Person change listener is called on the next iteration of the run loop because
// a referenced dog object changed.

RealmConfiguration config = new RealmConfiguration.Builder()
    .schemaVersion(2) // Must be bumped when the schema changes
    .migration(new MyMigration()) // Migration to run instead of throwing an exception
    .build()

// Example migration adding a new class
RealmMigration migration = new RealmMigration() {
  @Override
  public void migrate(DynamicRealm realm, long oldVersion, long newVersion) {

     // DynamicRealm exposes an editable schema
     RealmSchema schema = realm.getSchema();

     // Migrate to version 1: Add a new class
     // Example:
     // public Person extends RealmObject {
     //     private String name;
     //     private int age;
     //     // getters and setters left out for brevity
     // }
     if (oldVersion == 0) {
        schema.create("Person")
            .addField("name", String.class)
            .addField("age", int.class);
        oldVersion++;
     }

     // Migrate to version 2: Add a primary key + object references
     // Example:
     // public Person extends RealmObject {
     //     private String name;
     //     @PrimaryKey
     //     private int age;
     //     private Dog favoriteDog;
     //     private RealmList<Dog> dogs;
     //     // getters and setters left out for brevity
     // }
     if (oldVersion == 1) {
        schema.get("Person")
            .addField("id", long.class, FieldAttribute.PRIMARY_KEY)
            .addRealmObjectField("favoriteDog", schema.get("Dog"))
            .addRealmListField("dogs", schema.get("Dog"));
        oldVersion++;
     }
  }
}

RealmConfiguration config = new RealmConfiguration.Builder()
    .deleteRealmIfMigrationNeeded()
    .build()

byte[] key = new byte[64];
new SecureRandom().nextBytes(key);
RealmConfiguration config = new RealmConfiguration.Builder()
  .encryptionKey(key)
  .build();

Realm realm = Realm.getInstance(config);

dependencies {
	compile 'io.realm:android-adapters:1.4.0'
}

// Assuming we had a person class with a @PrimaryKey on the 'id' field ...
Intent intent = new Intent(getActivity(), ReceivingService.class);
intent.putExtra("person_id", person.getId());
getActivity().startService(intent);

// in onCreate(), onHandleIntent(), etc.
String personId = intent.getStringExtra("person_id");
Realm realm = Realm.getDefaultInstance();
Person person = realm.where(Person.class).equalTo("id", personId).findFirst();
// do something with the person ...
realm.close();

private class DownloadOrders extends AsyncTask<Void, Void, Long> {
    protected Long doInBackground(Void... voids) {
        // Now in a background thread.

        // Open the Realm
        Realm realm = Realm.getDefaultInstance();
        try {
            // Work with Realm
            realm.createAllFromJson(Order.class, api.getNewOrders());
            Order firstOrder = realm.where(Order.class).findFirst();
            long orderId = firstOrder.getId(); // Id of order
            return orderId;
        } finally {
            realm.close();
        }
    }

    protected void onPostExecute(Long orderId) {
        // Back on the Android mainThread
        // do something with orderId such as query Realm
        // for the order and perform some operation with it.
    }
}

public class OrdersIntentService extends IntentService {
    public OrdersIntentService(String name) {
        super("OrdersIntentService");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        // Now in a background thread.

        // Open the Realm
        Realm realm = Realm.getDefaultInstance();
        // Work with Realm
        realm.createAllFromJson(Order.class, api.getNewOrders());
        Order firstOrder = realm.where(Order.class).findFirst();
        long orderId = firstOrder.getId(); // Id of order
        realm.close();
    }
}

// Using the User class
public class User extends RealmObject {
    private String name;
    private String email;
    // getters and setters left out ...
}

Gson gson = new GsonBuilder().create();
String json = "{ name : 'John', email : 'john@corporation.com' }";
User user = gson.fromJson(json, User.class);

public class Person extends RealmObject {
    @Ignore
    Drawable avatar;
    // other fields, etc
}

public boolean shouldSkipField(FieldAttributes f) {
  return f.getDeclaringClass().equals(RealmObject.class) || f.getDeclaringClass().equals(Drawable.class);
}

java.lang.NoClassDefFoundError: rx.Observable
at libcore.reflect.InternalNames.getClass(InternalNames.java:55)

package rx;

public class Observable {
    // Dummy class required for Jackson-Databind support if
    // RxJava is not a project dependency.
}

// All classes that extend RealmObject will have a matching RealmProxy class created
// by the annotation processor. Parceler must be made aware of this class. Note that
// the class is not available until the project has been compiled at least once.
@Parcel(implementations = { PersonRealmProxy.class },
        value = Parcel.Serialization.BEAN,
        analyze = { Person.class })
public class Person extends RealmObject {
	// ...
}

compile "org.parceler:parceler-api:1.0.3"
apt "org.parceler:parceler:1.0.3"

GitHubService service = restAdapter.create(GitHubService.class);
List<Repo> repos = service.listRepos("octocat");

// Copy elements from Retrofit to Realm to persist them.
realm.beginTransaction();
List<Repo> realmRepos = realm.copyToRealmOrUpdate(repos);
realm.commitTransaction();

// Combining Realm, Retrofit and RxJava (Using Retrolambda syntax for brevity)
// Load all persons and merge them with their latest stats from GitHub (if they have any)
Realm realm = Realm.getDefaultInstance();
GitHubService api = retrofit.create(GitHubService.class);
realm.where(Person.class).isNotNull("username").findAllAsync().asObservable()
    .filter(persons.isLoaded)
    .flatMap(persons -> Observable.from(persons))
    .flatMap(person -> api.user(person.getGithubUserName())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe(user -> showUser(user));

dependencies {
  compile 'io.reactivex:rxjava:1.1.0'
}

RealmConfiguration config = new RealmConfiguration.Builder()
  .rxFactory(new MyRxFactory())
  .build()

crashlytics {
  enableNdk true
}

// Setup Realm in your Application
public class MyApplication extends Application {
    @Override
    public void onCreate() {
        super.onCreate();
        RealmConfiguration realmConfiguration = new RealmConfiguration.Builder().build();
        Realm.setDefaultConfiguration(realmConfiguration);
    }
}

// onCreate()/onDestroy() overlap when switching between activities so onCreate()
// on Activity 2 will be called before onDestroy() on Activity 1.
public class MyActivity extends Activity {
    private Realm realm;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        realm = Realm.getDefaultInstance();
    }

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

// Use onStart()/onStop() for Fragments as onDestroy() might not be called.
public class MyFragment extends Fragment {
    private Realm realm;

    @Override
    public void onStart() {
        super.onStart();
        realm = Realm.getDefaultInstance();
    }

    @Override
    public void onStop() {
        super.onStop();
        realm.close();
    }
}

public class MyActivity extends Activity {

    private Realm realm;
    private RealmResults<Person> allPersons;
    private RealmChangeListener realmListener = new RealmChangeListener<Realm>() {
        @Override
        public void onChange(Realm realm) {
            // Just redraw the views. `allPersons` already contain the
            // latest data.
            invalidateView();
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        realm = Realm.getDefaultInstance();
        realm.addRealmChangeListener(listener);
        allPerson = realm.where(Person.class).findAll(); // Create the "live" query result
        setupViews(); // Initial setup of views
        invalidateView(); // Redraw views with data
    }

    // ...
}

realm {
  syncEnabled = true;
}

SyncCredentials myCredentials = SyncCredentials.usernamePassword(username, password, true);

String token = "..."; // a string representation of a token obtained by Google Login API
SyncCredentials myCredentials = SyncCredentials.google(token);

String token = "..."; // a string representation of a token obtained by Facebook Login API
SyncCredentials myCredentials = SyncCredentials.facebook(token);

String authURL = "http://my.realm-auth-server.com:9080/auth";
SyncUser user = SyncUser.login(myCredentials, authURL);

SyncUser user = getUserFromLogin();
String serverURL = "realm://my.realm-server.com/~/default";
SyncConfiguration configuration = new SyncConfiguration.Builder(user, serverURL).build();

SyncUser user = SyncUser.getCurrentUser();

String userJson = user.toJson();

SyncUser user = SyncUser.fromJson(userJson);

user.logout();

Realm realm = Realm.getInstance(syncConfiguration);

RealmLog.setLevel(Log.VERBOSE);

SyncConfiguration configuration = new SyncConfigurtion.Builder(user, serverURL)
  .errorHandler(new Session.ErrorHandler() {
    void onError(Session session, ObjectServerError error) {
        // do some error handling
    }
  })
  .build();

SyncManager.setDefaultSessionErrorHandler(myErrorHandler);

splits {
    abi {
        enable true
        reset()
        include 'armeabi-v7a', 'arm64-v8a', 'mips', 'x86', 'x86_64'
    }
}

android {
    //...
    packagingOptions {
        exclude "lib/arm64-v8a/librealm-jni.so"
    }
    //...
}