ToMany: added indexOfId() and getById()

Author: greenrobot

objectbox-java/src/main/java/io/objectbox/reactive/DataSubscriptionList.java

@@ -0,0 +1,30 @@
+package io.objectbox.reactive;
+
+import java.util.List;
+
+public class DataSubscriptionList implements DataSubscription {
+    private boolean canceled;
+    List<DataSubscription> subscriptions;
+
+    public synchronized void add(DataSubscription subscription) {
+        subscriptions.add(subscription);
+    }
+
+    @Override
+    public synchronized void cancel() {
+        canceled = true;
+        for (DataSubscription subscription : subscriptions) {
+            subscription.cancel();
+        }
+        subscriptions.clear();
+    }
+
+    @Override
+    public synchronized boolean isCanceled() {
+        return canceled;
+    }
+
+    public synchronized int getActiveSubscriptionCount() {
+        return subscriptions.size();
+    }
+}

objectbox-java/src/main/java/io/objectbox/relation/ToMany.java

@@ -529,6 +529,38 @@ public boolean hasAll(QueryFilter<TARGET> filter) {
         return true;
     }
 
+    @Beta
+    /** Gets an object by its entity ID. */
+    public TARGET getById(long id) {
+        ensureEntities();
+        Object[] objects = entities.toArray();
+        IdGetter<TARGET> idGetter = relationInfo.targetInfo.getIdGetter();
+        for (Object target : objects) {
+            TARGET candidate = (TARGET) target;
+            if (idGetter.getId(candidate) == id) {
+                return candidate;
+            }
+        }
+        return null;
+    }
+
+    @Beta
+    /** Gets the index of the object with the given entity ID. */
+    public int indexOfId(long id) {
+        ensureEntities();
+        Object[] objects = entities.toArray();
+        IdGetter<TARGET> idGetter = relationInfo.targetInfo.getIdGetter();
+        int index = 0;
+        for (Object target : objects) {
+            TARGET candidate = (TARGET) target;
+            if (idGetter.getId(candidate) == id) {
+                return index;
+            }
+            index++;
+        }
+        return -1;
+    }
+
     /**
      * For internal use only; do not use in your app.
      * Called after relation source entity is put (so we have its ID).

tests/objectbox-java-test/src/main/java/io/objectbox/relation/ToManyTest.java

@@ -26,10 +26,7 @@
 import io.objectbox.TestUtils;
 import io.objectbox.query.QueryFilter;
 
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.*;
 
 public class ToManyTest extends AbstractRelationTest {
 
@@ -315,6 +312,7 @@ public void testSortById() {
         assertEquals("new1", toMany.get(3).getText());
         assertEquals("new2", toMany.get(4).getText());
     }
+
     @Test
     public void testHasA() {
         Customer customer = putCustomerWithOrders(3);
@@ -341,12 +339,32 @@ public boolean keep(Order entity) {
             }
         };
         assertTrue(toMany.hasAll(filter));
-        toMany.get(0).text="nope";
+        toMany.get(0).text = "nope";
         assertFalse(toMany.hasAll(filter));
         toMany.clear();
         assertFalse(toMany.hasAll(filter));
     }
 
+    @Test
+    public void testIndexOfId() {
+        Customer customer = putCustomerWithOrders(3);
+        ToMany<Order> toMany = (ToMany<Order>) customer.orders;
+        assertEquals(1, toMany.indexOfId(toMany.get(1).getId()));
+        assertEquals(2, toMany.indexOfId(toMany.get(2).getId()));
+        assertEquals(0, toMany.indexOfId(toMany.get(0).getId()));
+        assertEquals(-1, toMany.indexOfId(42));
+    }
+
+    @Test
+    public void testGetById() {
+        Customer customer = putCustomerWithOrders(3);
+        ToMany<Order> toMany = (ToMany<Order>) customer.orders;
+        assertEquals(toMany.get(1), toMany.getById(toMany.get(1).getId()));
+        assertEquals(toMany.get(2), toMany.getById(toMany.get(2).getId()));
+        assertEquals(toMany.get(0), toMany.getById(toMany.get(0).getId()));
+        assertNull(toMany.getById(42));
+    }
+
     @Test
     public void testSerializable() throws IOException, ClassNotFoundException {
         Customer customer = new Customer();