Realm Useful Helpers

This library is inspired from realmfieldnameshelper and added extra fetaures.

Features:

• Auto generate helper classes that can help make Realm queries more type safe
• Map Gson object field names to Realm field names and vice versa

For each Realm model class a corresponding <class>Fields class is created with static references to all queryable field names.

Installation

Include the following dependency in your gradle.build file

annotationProcessor 'com.github.abou7mied:realm-useful-helpers:1.0.3'

Usage

The library adds an annotation processor that automatically detects all Realm model classes and generated an extra class called <className>Fields. This class will contain static references to all field names that can be queried.

public class Person extends RealmObject {

    @PrimaryKey
    @SerializedName("person_name")
    private String name;

    @SerializedName("has_dogs")
    private boolean hasDogs;

    @SerializedName("favorite_dog")
    private Dog favoriteDog;

    @SerializedName("dogs")
    private RealmList<Dog> dogs;

    @Ignore
    private transient int random;

    public void setName(String name) {
        this.name = name;
    }

    public void setHasDogs(boolean hasDogs) {
        this.hasDogs = hasDogs;
    }
}

PersonFields class is automatically generated

package io.realm.fields;

import java.lang.String;

public final class PersonFields {
  public static final String NAME = "name";

  public static final String HAS_DOGS = "hasDogs";

  public static final class FAVORITE_DOG {
    public static final String $ = "favoriteDog";

    public static final String NAME = "favoriteDog.name";
  }

  public static final class DOGS {
    public static final String $ = "dogs";

    public static final String NAME = "dogs.name";
  }
}

And can be used when creating queries

Realm realm = Realm.getDefaultInstance();
RealmResults<Person> results = realm.where(Person.class)
                                    .equalTo(PersonFields.NAME, "John")
                                    .findAll();

RealmResults<Person> results = realm.where(Person.class)
                                    .equalTo(PersonFields.FAVORITE_DOG.NAME, "Fido")
                                    .findAll();

RealmJsonMapping class is generated too

Person person = new Person();
person.setName("John");
person.setHasDogs(false);

Gson gson = new Gson();
String jsonString = gson.toJson(person); // {"person_name":"John","has_dogs":false}
Log.d("jsonString", jsonString + "");

try {
    JSONObject personJson = new JSONObject(jsonString);
    final JSONObject mapped = RealmJsonMapping.mapJsonObjectToRealm(PersonFields.class, personJson); // {"name":"John","hasDogs":false}
    Log.d("mapped", mapped + "");
    Realm.getDefaultInstance().executeTransactionAsync(new Realm.Transaction() {
        @Override
        public void execute(Realm realm) {
            Realm.getDefaultInstance().createOrUpdateObjectFromJson(Person.class, mapped);
        }
    });
} catch (JSONException e) {
    e.printStackTrace();
}

RealmJsonMapping Methods

JSONObject mapJsonObjectToRealm(Class cls, JSONObject object) mapping Gson field names of an object to Realm names

JSONArray mapJsonArrayToRealm(Class cls, JSONArray array) mapping Gson field names of all object in the array to Realm names

String getRealmName(Class cls, String key) get the corresponding realm field name of gson name