This document describes Realm and its core components for working with objects in Realm databases. It discusses RealmObject, RealmObjectProxy, RealmList, and RealmResults which allow defining and querying object schemas and relationships. It also covers how to import and export RealmObjects as JSON using various libraries like Gson, Moshi, Jackson, and a custom Rson library. Transactions and exporting data to storage or via email is demonstrated using the Royal wrapper library.

1. Realm + Json
The Finest Artist

2. Realm
RealmObject
RealmObjectProxy
RealmList
RealmResult
RealmChangeListener

3. RealmObject
public abstract class RealmObject {
protected Row row;
protected Realm realm;
public void removeFromRealm() { /* ... */ }
public boolean isValid() { /* ... */ }
protected static Realm getRealm(RealmObject obj) { /* ... */ }
protected static Row getRow(RealmObject obj) { /* ... */ }
}

4. RealmObjectProxy
public interface RealmObjectProxy {
}

5. RealmList
public class RealmList<E extends RealmObject> extends AbstractList<E> {
private final boolean managedMode;
private Class<E> clazz;
private LinkView view;
private Realm realm;
private List<E> nonManagedList;
public RealmList() { /* ... */ }
public RealmList(E... objects) { /* ... */ }
RealmList(Class<E> clazz, LinkView view, Realm realm) { /* ... */ }
@Override public void add(int location, E object) { /* ... */ }
@Override public boolean add(E object) { /* ... */ }
@Override public E set(int location, E object) { /* ... */ }

6. RealmList
private E copyToRealmIfNeeded(E object) { /* ... */ }
public void move(int oldPos, int newPos) { /* ... */ }
@Override public void clear() { /* ... */ }
@Override public E remove(int location) { /* ... */ }
@Override public E get(int location) { /* ... */ }
public E first() { /* ... */ }
public E last() { /* ... */ }
@Override public int size() { /* ... */ }
public RealmQuery<E> where() { /* ... */ }
private void checkValidObject(E object) { /* ... */ }
private void checkIndex(int location) { /* ... */ }
@Override public String toString() { /* ... */ }
}

7. Owner
public class Owner extends RealmObject {
private String name;
private RealmList<Dog> dogs;
private Cat cat;
public Cat getCat() { /* ... */ }
public void setCat(Cat cat) { /* ... */ }
public RealmList<Dog> getDogs() { /* ... */ }
public void setDogs(RealmList<Dog> dogs) { /* ... */ }
public String getName() { /* ... */ }
public void setName(String name) { /* ... */ }
}

8. OwnerRealmProxy
public class OwnerRealmProxy extends Owner implements RealmObjectProxy {
private static long INDEX_NAME;
private static long INDEX_DOGS;
private static long INDEX_CAT;
private static final List<String> FIELD_NAMES;
@Override public String getName() { /* ... */ }
@Override public void setName(String value) { /* ... */ }
@Override public RealmList<Dog> getDogs() { /* ... */ }
@Override public void setDogs(RealmList<Dog> value) { /* ... */ }
@Override public Cat getCat() { /* ... */ }
@Override public void setCat(Cat value) { /* ... */ }
}

9. When?
realm.beginTransaction();
{
Owner owner = new Owner();
owner.setName("Leonardo");
}
realm.commitTransaction();
Owner owner = new Owner();
owner.setName("Leonardo");
realm.beginTransaction();
{
Owner ownerProxy = realm.copyToRealm(owner);
}
realm.commitTransaction();

10. JsonString to RealmObject
public <E extends RealmObject> void createAllFromJson(Class<E> clazz, JSONArray json) { /*...*/ }
public <E extends RealmObject> void createOrUpdateAllFromJson(Class<E> clazz, JSONArray json) { /*...*/ }
public <E extends RealmObject> void createAllFromJson(Class<E> clazz, String json) { /*...*/ }
public <E extends RealmObject> void createOrUpdateAllFromJson(Class<E> clazz, String json) { /*...*/}
public <E extends RealmObject> E createObjectFromJson(Class<E> clazz, JSONObject json) { /*...*/ }
public <E extends RealmObject> E createOrUpdateObjectFromJson(Class<E> clazz, JSONObject json) { /*…*/ }
public <E extends RealmObject> E createObjectFromJson(Class<E> clazz, String json) { /*...*/ }
public <E extends RealmObject> E createOrUpdateObjectFromJson(Class<E> clazz, String json) { /*...*/}

11. RealmObject to JsonString
Moshi (Square)
Gson (Google)
Jackson (FasterXML)
JsonPullParser (Vvakame)
Serialize (Cmelchior/Gist)
Rson (TheFinestArtist)
http://www.slideshare.net/TheFinestArtist/realm-51344456

12. RealmObject & ProxyObject
AllTypes allTypes;
Logger.d("Gson(Realm Object)");
Logger.json(gson.toJson(allTypes));
realm.beginTransaction();
AllTypes allTypesProxy = realm.copyToRealm(allTypes);
realm.commitTransaction();
Logger.d("Gson(Proxy Object)");
Logger.json(gson.toJson(allTypesProxy));

13. Moshi
Moshi moshi = new Moshi.Builder()
.add(new MoshiDateAdapter())
.build();
JsonAdapter<AllTypes> adapter = moshi.adapter(AllTypes.class);
// No JsonAdapter for
java.lang.Class<com.thefinestartist.realm.json.models.Dog>
annotated []

14. Gson
RealmObject
{
"columnBinary": [
0,
1,
2,
3,
4,
5,
6,
7
],
"columnBoolean": true,
"columnDate": "Aug 5, 2015 8:30:55 PM",
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnString": "allType"
}
ProxyObject
{
"columnBoolean": true,
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123
}
Doesn’t work for ProxyObject

15. Jackson
RealmObject
{
"columnBinary": "AAECAwQFBgc=",
"columnBoolean": true,
"columnDate": 1438821055494,
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnRealmList": null,
"columnRealmObject": null,
"columnString": "allType"
}
ProxyObject
{
"columnBinary": "AAECAwQFBgc=",
"columnBoolean": true,
"columnDate": 1438821055000,
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnRealmList": [],
"columnRealmObject": null,
"columnString": "allType"
}
@JsonIgnoreProperties({“valid”})

16. Json Pull Parser
RealmObject
{
"columnString": "allType",
"columnLong": 123,
"columnFloat": 12.3,
"columnDouble": 1.23,
"columnBoolean": true,
"columnDate": 1438821055494,
"columnRealmObject": null
}
ProxyObject
{
"columnString": "allType",
"columnLong": 123,
"columnFloat": 12.3,
"columnDouble": 1.23,
"columnBoolean": true,
"columnDate": 1438821055000,
"columnRealmObject": null
}
Doesn’t work for RealmList!!

17. Serialize
RealmObject
{
"columnBinary": [
0,
1,
2,
3,
4,
5,
6,
7
],
"columnBoolean": true,
"columnDate": "Aug 5, 2015 8:30:55 PM",
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnString": "allType"
}
ProxyObject
{
"columnBinary": [
0,
1,
2,
3,
4,
5,
6,
7
],
"columnBoolean": true,
"columnDate": "Aug 5, 2015 8:30:55 PM",
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnString": "allType"
}

18. Serialize
public class AllTypesSerializer implements JsonSerializer<AllTypes> {
@Override
public JsonElement serialize(AllTypes src, Type typeOfSrc, JsonSerializationContext context) {
final JsonObject jsonObject = new JsonObject();
jsonObject.addProperty("columnString", src.getColumnString());
jsonObject.addProperty("columnLong", src.getColumnLong());
jsonObject.addProperty("columnFloat", src.getColumnFloat());
jsonObject.addProperty("columnDouble", src.getColumnDouble());
jsonObject.addProperty("columnBoolean", src.isColumnBoolean());
jsonObject.addProperty("columnDate", DateUtil.getDateFormat(src.getColumnDate()));
jsonObject.add("columnBinary", context.serialize(src.getColumnBinary()));
jsonObject.add("columnRealmObject", context.serialize(src.getColumnRealmObject()));
jsonObject.add("columnRealmList", context.serialize(src.getColumnRealmList()));
return jsonObject;
}
}

19. Rson
RealmObject
{
"columnBinary": [
0,
1,
2,
3,
4,
5,
6,
7
],
"columnBoolean": true,
"columnDate": "Aug 5, 2015 8:30:55 PM",
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnString": "allType"
}
ProxyObject
{
"columnBinary": [
0,
1,
2,
3,
4,
5,
6,
7
],
"columnBoolean": true,
"columnDate": "Aug 5, 2015 8:30:55 PM",
"columnDouble": 1.23,
"columnFloat": 12.3,
"columnLong": 123,
"columnString": "allType"
}

20. Rson
Rson.toJsonString(RealmObject object);
Rson.toJsonString(RealmObject object, int depth);

21. Royal
https://github.com/TheFinestArtist/Royal-Android

22. Royal
Royal
RoyalDatabase
RoyalTransaction
RoyalExport
Rson

23. Dependencies
dependencies {
compile 'com.thefinestartist:royal:0.82.0.6'
}

24. Dependencies
dependencies {
compile 'com.thefinestartist:royal:0.82.0.6'
}
public class App extends Application {
@Override
public void onCreate() {
super.onCreate();
Royal.joinWith(this);
}
}

25. RoyalDatabase
public class SecondaryDatabase extends RoyalDatabase {
public String getFileName() { return "secondary"; }
public boolean forCache() { return false; }
public byte[] getEncryptionKey() { return null; }
public int getVersion() { return 0; }
public boolean shouldDeleteIfMigrationNeeded() { return false; }
public Set<Object> getModules() {
Set<Object> set = new HashSet<>();
set.add(new SecondaryModule());
return set;
}
@Override public long execute(Realm realm, long version) {
return getVersion();
}
}

26. RoyalDatabase
public class App extends Application {
@Override
public void onCreate() {
super.onCreate();
Royal.joinWith(this);
Royal.addDatabase(new SecondaryDatabase());
}
}
RealmConfiguration configuration =
Royal.getConfigurationOf(SecondaryDatabase.class);

27. RoyalTransaction
// RealmList, RealmResults, RealmObject, List<? extends RealmObject>
RoyalTransaction.create(Class<? extends RoyalDatabase> clazz, Object... objects);
RoyalTransaction.create(RealmConfiguration configuration, Object... objects);
RoyalTransaction.create(Realm realm, Object... objects);
RoyalTransaction.save(Class<? extends RoyalDatabase> clazz, Object... objects);
RoyalTransaction.save(RealmConfiguration configuration, Object... objects);
RoyalTransaction.save(Realm realm, Object... objects);
RoyalTransaction.delete(Class<? extends RoyalDatabase> clazz, Object... objects);
RoyalTransaction.delete(RealmConfiguration configuration, Object... objects);
RoyalTransaction.delete(Realm realm, Object... objects);

28. RoyalTransaction
User user1 = new User();
user1.setName("Leonardo Taehwan Kim");
user1.setEmail("contact@thefinestartist.com");
user1.setUsername("TheFinestArtist");
User user2 = new User();
user2.setName("Leonardo Taehwan Kim");
user2.setEmail("contact@thefinestartist.com");
user2.setUsername("TheFinestArtist");
RoyalTransaction.save(realm, user1, user2);
RoyalTransaction.save(RealmDatabase.class, user1, user2);

29. RoyalExport
RoyalExport.toEmail(Class<? extends RoyalDatabase>... clazzes);
RoyalExport.toEmail(String email, Class<? extends RoyalDatabase>... clazzes);
RoyalExport.toEmail(String email, Intent intent, Class<? extends RoyalDatabase>... clazzes);
RoyalExport.toEmail(RealmConfiguration... configurations);
RoyalExport.toEmail(String email, RealmConfiguration... configurations);
RoyalExport.toEmail(String email, Intent intent, RealmConfiguration... configurations);
RoyalExport.toEmail(Realm... realms);
RoyalExport.toEmail(String email, Realm... realms);
RoyalExport.toEmail(String email, Intent intent, Realm... realms);
RoyalExport.toEmailAsRawFile();
RoyalExport.toEmailAsRawFile(String email);
RoyalExport.toEmailAsRawFile(String email, Intent intent);
RoyalExport.toExternalStorage(Class<? extends RoyalDatabase>... clazzes)
RoyalExport.toExternalStorage(RealmConfiguration... configurations);
RoyalExport.toExternalStorage(Realm... realms);
RoyalExport.toExternalStorageAsRawFile();

30. Rson
Rson.toJsonString(RealmObject object);
Rson.toJsonString(RealmObject object, int depth);

33. Thank You :)