Add findFirst(int), findLast(int) and findRandom(int)

realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java

@@ -1372,6 +1372,72 @@ public void findFirst_subQuery_withSorting() {
         assertEquals("Bella", dog.getName());
     }
 
+    @Test
+    public void findFirst_limit() {
+        realm.beginTransaction();
+
+        Owner owner1 = realm.createObject(Owner.class);
+        owner1.setName("Owner 1");
+
+        Owner owner2 = realm.createObject(Owner.class);
+        owner2.setName("Owner 2");
+
+        Owner owner3 = realm.createObject(Owner.class);
+        owner3.setName("Owner 3");
+
+        Owner owner4 = realm.createObject(Owner.class);
+        owner4.setName("Owner 4");
+
+        realm.commitTransaction();
+
+        RealmResults<Owner> owners = realm.where(Owner.class).findFirst(2);
+        assertEquals(2, subQueryResult.size());
+    }
+
+    @Test
+    public void findLast_limit() {
+        realm.beginTransaction();
+
+        Owner owner1 = realm.createObject(Owner.class);
+        owner1.setName("Owner 1");
+
+        Owner owner2 = realm.createObject(Owner.class);
+        owner2.setName("Owner 2");
+
+        Owner owner3 = realm.createObject(Owner.class);
+        owner3.setName("Owner 3");
+
+        Owner owner4 = realm.createObject(Owner.class);
+        owner4.setName("Owner 4");
+
+        realm.commitTransaction();
+
+        RealmResults<Owner> owners = realm.where(Owner.class).findLast(2);
+        assertEquals(2, subQueryResult.size());
+    }
+
+    @Test
+    public void findRandom_limit() {
+        realm.beginTransaction();
+
+        Owner owner1 = realm.createObject(Owner.class);
+        owner1.setName("Owner 1");
+
+        Owner owner2 = realm.createObject(Owner.class);
+        owner2.setName("Owner 2");
+
+        Owner owner3 = realm.createObject(Owner.class);
+        owner3.setName("Owner 3");
+
+        Owner owner4 = realm.createObject(Owner.class);
+        owner4.setName("Owner 4");
+
+        realm.commitTransaction();
+
+        RealmResults<Owner> owners = realm.where(Owner.class).findRandom(2);
+        assertEquals(2, subQueryResult.size());
+    }
+
     @Test
     public void georgian() {
         String words[] = {"მონაცემთა ბაზა", "მიწისქვეშა გადასასვლელი", "რუსთაველის გამზირი",

realm/realm-library/src/main/java/io/realm/RealmQuery.java

@@ -1765,6 +1765,56 @@ public long count() {
         return lazyFindAll().size();
     }
 
+    /**
+     * Finds first n objects that fulfill the query conditions.
+     *
+     * @return a {@link io.realm.RealmResults} containing objects. If no objects match the condition, a list with zero
+     * objects is returned.
+     * @see io.realm.RealmResults
+     */
+    @SuppressWarnings("unchecked")
+    public RealmResults<E> findFirst(int limit) {
+        return limit(limit).findAll();
+    }
+
+    /**
+     * Finds last n objects that fulfill the query conditions.
+     *
+     * @return a {@link io.realm.RealmResults} containing objects. If no objects match the condition, a list with zero
+     * objects is returned.
+     * @see io.realm.RealmResults
+     */
+    @SuppressWarnings("unchecked")
+    public RealmResults<E> findLast(int limit) {
+        if (limit < 1) {
+            throw new IllegalArgumentException("Only positive numbers above 0 is allowed. Yours was: " + limit);
+        }
+
+        RealmResults<E> results = findAll();
+        results = results.subList(Math.max(results.size() - limit, 0), results.size());
+        Collections.reverse(results);
+        return results;
+    }
+
+    /**
+     * Finds random n objects that fulfill the query conditions.
+     *
+     * @return a {@link io.realm.RealmResults} containing objects. If no objects match the condition, a list with zero
+     * objects is returned.
+     * @see io.realm.RealmResults
+     */
+    @SuppressWarnings("unchecked")
+    public RealmResults<E> findRandom(int limit) {
+        if (limit < 1) {
+            throw new IllegalArgumentException("Only positive numbers above 0 is allowed. Yours was: " + limit);
+        }
+
+        RealmResults<E> results = findAll();
+        Collections.shuffle(results);
+        results = results.subList(0, Math.min(limit, results.size()));
+        return results;
+    }
+
     /**
      * Finds all objects that fulfill the query conditions.
      *