Add Filter parameter to DataProvider

Change-Id: Ic65b8decb3ac8d4dde9bca6cfb40a2a70f461e91

21 files changed, 108 insertions, 92 deletions

diff --git a/server/src/main/java/com/vaadin/data/Listing.java b/server/src/main/java/com/vaadin/data/Listing.java
index c866187518..8f94296057 100644
--- a/server/src/main/java/com/vaadin/data/Listing.java
+++ b/server/src/main/java/com/vaadin/data/Listing.java
@@ -24,7 +24,7 @@ import com.vaadin.server.data.DataProvider;
  * A generic interface for components that show a list of data.
  *
  * @author Vaadin Ltd.
- * 
+ *
  * @param <T>
  *            the item data type
  * @since 8.0
@@ -36,16 +36,16 @@ public interface Listing<T> extends Serializable {
      *
      * @return the data provider, not null
      */
-    DataProvider<T> getDataProvider();
+    DataProvider<T, ?> getDataProvider();
 
     /**
-     * Sets the data provider for this listing. The data provider is
-     * queried for displayed items as needed.
+     * Sets the data provider for this listing. The data provider is queried for
+     * displayed items as needed.
      *
      * @param dataProvider
      *            the data provider, not null
      */
-    void setDataProvider(DataProvider<T> dataProvider);
+    void setDataProvider(DataProvider<T, ?> dataProvider);
 
     /**
      * Sets the collection of data items of this listing.
diff --git a/server/src/main/java/com/vaadin/server/data/AbstractDataProvider.java b/server/src/main/java/com/vaadin/server/data/AbstractDataProvider.java
index 531d77e44c..adb1bed36d 100644
--- a/server/src/main/java/com/vaadin/server/data/AbstractDataProvider.java
+++ b/server/src/main/java/com/vaadin/server/data/AbstractDataProvider.java
@@ -22,14 +22,19 @@ import com.vaadin.event.EventRouter;
 import com.vaadin.shared.Registration;
 
 /**
- * Abstract data provider implementation which takes care of refreshing data from
- * the underlying data provider.
- * 
+ * Abstract data provider implementation which takes care of refreshing data
+ * from the underlying data provider.
+ *
+ * @param <T>
+ *            data type
+ * @param <F>
+ *            filter type
+ *
  * @author Vaadin Ltd
  * @since 8.0
  *
  */
-public abstract class AbstractDataProvider<T> implements DataProvider<T> {
+public abstract class AbstractDataProvider<T, F> implements DataProvider<T, F> {
 
     private EventRouter eventRouter;
 
@@ -60,8 +65,8 @@ public abstract class AbstractDataProvider<T> implements DataProvider<T> {
      *            the activation method.
      *
      */
-    protected void addListener(Class<?> eventType, DataProviderListener listener,
-            Method method) {
+    protected void addListener(Class<?> eventType,
+            DataProviderListener listener, Method method) {
         if (eventRouter == null) {
             eventRouter = new EventRouter();
         }
diff --git a/server/src/main/java/com/vaadin/server/data/BackEndDataProvider.java b/server/src/main/java/com/vaadin/server/data/BackEndDataProvider.java
index 8d267f1230..0f83710d90 100644
--- a/server/src/main/java/com/vaadin/server/data/BackEndDataProvider.java
+++ b/server/src/main/java/com/vaadin/server/data/BackEndDataProvider.java
@@ -27,11 +27,13 @@ import com.vaadin.server.SerializableFunction;
  *
  * @param <T>
  *            data provider data type
+ * @param <F>
+ *            data provider filter type
  */
-public class BackEndDataProvider<T> extends AbstractDataProvider<T> {
+public class BackEndDataProvider<T, F> extends AbstractDataProvider<T, F> {
 
-    private final SerializableFunction<Query<?>, Stream<T>> request;
-    private final SerializableFunction<Query<?>, Integer> sizeCallback;
+    private final SerializableFunction<Query<F>, Stream<T>> request;
+    private final SerializableFunction<Query<F>, Integer> sizeCallback;
 
     /**
      * Constructs a new DataProvider to request data from an arbitrary back end
@@ -43,8 +45,8 @@ public class BackEndDataProvider<T> extends AbstractDataProvider<T> {
      *            function that return the amount of data in back end for query
      */
     public BackEndDataProvider(
-            SerializableFunction<Query<?>, Stream<T>> request,
-            SerializableFunction<Query<?>, Integer> sizeCallback) {
+            SerializableFunction<Query<F>, Stream<T>> request,
+            SerializableFunction<Query<F>, Integer> sizeCallback) {
         Objects.requireNonNull(request, "Request function can't be null");
         Objects.requireNonNull(sizeCallback, "Size callback can't be null");
         this.request = request;
@@ -52,12 +54,12 @@ public class BackEndDataProvider<T> extends AbstractDataProvider<T> {
     }
 
     @Override
-    public Stream<T> fetch(Query query) {
+    public Stream<T> fetch(Query<F> query) {
         return request.apply(query);
     }
 
     @Override
-    public int size(Query query) {
+    public int size(Query<F> query) {
         return sizeCallback.apply(query);
     }
 
@@ -69,14 +71,15 @@ public class BackEndDataProvider<T> extends AbstractDataProvider<T> {
      *            directions
      * @return new data provider with modified sorting
      */
-    public BackEndDataProvider<T> sortingBy(
+    public BackEndDataProvider<T, F> sortingBy(
             List<SortOrder<String>> sortOrders) {
         return new BackEndDataProvider<>(query -> {
             List<SortOrder<String>> queryOrder = new ArrayList<>(
                     query.getSortOrders());
             queryOrder.addAll(sortOrders);
-            return request.apply(new Query<>(query.getLimit(),
-                    query.getOffset(), queryOrder, query.getFilter()));
+            return request
+                    .apply(new Query<>(query.getLimit(), query.getOffset(),
+                            queryOrder, query.getFilter().orElse(null)));
         }, sizeCallback);
     }
 
diff --git a/server/src/main/java/com/vaadin/server/data/DataChangeEvent.java b/server/src/main/java/com/vaadin/server/data/DataChangeEvent.java
index 94d28fc9d3..6d7d2e8bfb 100644
--- a/server/src/main/java/com/vaadin/server/data/DataChangeEvent.java
+++ b/server/src/main/java/com/vaadin/server/data/DataChangeEvent.java
@@ -19,10 +19,10 @@ import java.util.EventObject;
 
 /**
  * An event fired when the data of a {@code DataProvider} changes.
- * 
- * 
+ *
+ *
  * @see DataProviderListener
- * 
+ *
  * @author Vaadin Ltd
  * @since 8.0
  *
@@ -36,13 +36,13 @@ public class DataChangeEvent extends EventObject {
      * @param source
      *            the data provider, not null
      */
-    public DataChangeEvent(DataProvider<?> source) {
+    public DataChangeEvent(DataProvider<?, ?> source) {
         super(source);
     }
 
     @Override
-    public DataProvider<?> getSource() {
-        return (DataProvider<?>) super.getSource();
+    public DataProvider<?, ?> getSource() {
+        return (DataProvider<?, ?>) super.getSource();
     }
 
 }
diff --git a/server/src/main/java/com/vaadin/server/data/DataCommunicator.java b/server/src/main/java/com/vaadin/server/data/DataCommunicator.java
index 46b8fa079a..fc66185aee 100644
--- a/server/src/main/java/com/vaadin/server/data/DataCommunicator.java
+++ b/server/src/main/java/com/vaadin/server/data/DataCommunicator.java
@@ -180,7 +180,7 @@ public class DataCommunicator<T> extends AbstractExtension {
     private final Collection<DataGenerator<T>> generators = new LinkedHashSet<>();
     private final ActiveDataHandler handler = new ActiveDataHandler();
 
-    private DataProvider<T> dataProvider = DataProvider.create();
+    private DataProvider<T, ?> dataProvider = DataProvider.create();
     private final DataKeyMapper<T> keyMapper;
 
     private boolean reset = false;
@@ -462,7 +462,7 @@ public class DataCommunicator<T> extends AbstractExtension {
      *
      * @return the data provider
      */
-    public DataProvider<T> getDataProvider() {
+    public DataProvider<T, ?> getDataProvider() {
         return dataProvider;
     }
 
@@ -472,7 +472,7 @@ public class DataCommunicator<T> extends AbstractExtension {
      * @param dataProvider
      *            the data provider to set, not null
      */
-    public void setDataProvider(DataProvider<T> dataProvider) {
+    public void setDataProvider(DataProvider<T, ?> dataProvider) {
         Objects.requireNonNull(dataProvider, "data provider cannot be null");
         this.dataProvider = dataProvider;
         detachDataProviderListener();
diff --git a/server/src/main/java/com/vaadin/server/data/DataProvider.java b/server/src/main/java/com/vaadin/server/data/DataProvider.java
index b99cbe5d75..441a57b559 100644
--- a/server/src/main/java/com/vaadin/server/data/DataProvider.java
+++ b/server/src/main/java/com/vaadin/server/data/DataProvider.java
@@ -23,20 +23,22 @@ import java.util.stream.Stream;
 import com.vaadin.shared.Registration;
 
 /**
- * Minimal DataProvider API for communication between the DataProvider and a back
- * end service.
+ * Minimal DataProvider API for communication between the DataProvider and a
+ * back end service.
  *
  * @author Vaadin Ltd.
- * 
+ *
  * @param <T>
  *            data type
+ * @param <F>
+ *            filter type
  *
  * @see ListDataProvider
  * @see BackEndDataProvider
  *
  * @since 8.0
  */
-public interface DataProvider<T> extends Serializable {
+public interface DataProvider<T, F> extends Serializable {
 
     /**
      * Gets whether the DataProvider content all available in memory or does it
@@ -53,17 +55,17 @@ public interface DataProvider<T> extends Serializable {
      *            query with sorting and filtering
      * @return the size of the data provider
      */
-    int size(Query t);
+    int size(Query<F> t);
 
     /**
      * Fetches data from this DataProvider using given {@code query}.
-     * 
+     *
      * @param query
      *            given query to request data
      * @return the result of the query request: a stream of data objects, not
      *         {@code null}
      */
-    Stream<T> fetch(Query query);
+    Stream<T> fetch(Query<F> query);
 
     /**
      * Refreshes all data based on currently available data in the underlying
@@ -87,10 +89,10 @@ public interface DataProvider<T> extends Serializable {
     Registration addDataProviderListener(DataProviderListener listener);
 
     /**
-     * This method creates a new {@link ListDataProvider} from a given Collection.
-     * The ListDataProvider creates a protective List copy of all the contents in
-     * the Collection.
-     * 
+     * This method creates a new {@link ListDataProvider} from a given
+     * Collection. The ListDataProvider creates a protective List copy of all
+     * the contents in the Collection.
+     *
      * @param <T>
      *            the data item type
      * @param items
@@ -103,9 +105,9 @@ public interface DataProvider<T> extends Serializable {
 
     /**
      * This method creates a new {@link ListDataProvider} from given objects.The
-     * ListDataProvider creates a protective List copy of all the contents in the
-     * array.
-     * 
+     * ListDataProvider creates a protective List copy of all the contents in
+     * the array.
+     *
      * @param <T>
      *            the data item type
      * @param items
diff --git a/server/src/main/java/com/vaadin/server/data/ListDataProvider.java b/server/src/main/java/com/vaadin/server/data/ListDataProvider.java
index 14527749a5..a67ce42eab 100644
--- a/server/src/main/java/com/vaadin/server/data/ListDataProvider.java
+++ b/server/src/main/java/com/vaadin/server/data/ListDataProvider.java
@@ -21,6 +21,8 @@ import java.util.Objects;
 import java.util.function.Function;
 import java.util.stream.Stream;
 
+import com.vaadin.server.SerializablePredicate;
+
 /**
  * {@link DataProvider} wrapper for {@link Collection}s. This class does not
  * actually handle the {@link Query} parameters.
@@ -28,7 +30,8 @@ import java.util.stream.Stream;
  * @param <T>
  *            data type
  */
-public class ListDataProvider<T> extends AbstractDataProvider<T> {
+public class ListDataProvider<T>
+        extends AbstractDataProvider<T, SerializablePredicate<T>> {
 
     private Comparator<T> sortOrder;
     private final Collection<T> backend;
@@ -50,7 +53,7 @@ public class ListDataProvider<T> extends AbstractDataProvider<T> {
      * Chaining constructor for making modified {@link ListDataProvider}s. This
      * Constructor is used internally for making sorted and filtered variants of
      * a base data provider with actual data.
-     * 
+     *
      * @param items
      *            the backend data from the original list data provider
      * @param sortOrder
@@ -72,8 +75,8 @@ public class ListDataProvider<T> extends AbstractDataProvider<T> {
     }
 
     /**
-     * Creates a new list data provider based on this list data provider with the
-     * given sort order.
+     * Creates a new list data provider based on this list data provider with
+     * the given sort order.
      * <p>
      * <b>NOTE</b>: this data provider is not modified in any way.
      *
@@ -86,8 +89,8 @@ public class ListDataProvider<T> extends AbstractDataProvider<T> {
     }
 
     /**
-     * Creates a new list data provider based on this list data provider with the
-     * given sort order.
+     * Creates a new list data provider based on this list data provider with
+     * the given sort order.
      * <p>
      * <b>NOTE</b>: this data provider is not modified in any way.
      * <p>
diff --git a/server/src/main/java/com/vaadin/ui/AbstractListing.java b/server/src/main/java/com/vaadin/ui/AbstractListing.java
index 99dd6e5eb1..f49d8715de 100644
--- a/server/src/main/java/com/vaadin/ui/AbstractListing.java
+++ b/server/src/main/java/com/vaadin/ui/AbstractListing.java
@@ -133,12 +133,12 @@ public abstract class AbstractListing<T> extends AbstractComponent
     }
 
     @Override
-    public void setDataProvider(DataProvider<T> dataProvider) {
+    public void setDataProvider(DataProvider<T, ?> dataProvider) {
         getDataCommunicator().setDataProvider(dataProvider);
     }
 
     @Override
-    public DataProvider<T> getDataProvider() {
+    public DataProvider<T, ?> getDataProvider() {
         return getDataCommunicator().getDataProvider();
     }
 
diff --git a/server/src/main/java/com/vaadin/ui/CheckBoxGroup.java b/server/src/main/java/com/vaadin/ui/CheckBoxGroup.java
index a3f99e7b27..eb61d2242d 100644
--- a/server/src/main/java/com/vaadin/ui/CheckBoxGroup.java
+++ b/server/src/main/java/com/vaadin/ui/CheckBoxGroup.java
@@ -64,7 +64,7 @@ public class CheckBoxGroup<T> extends AbstractMultiSelect<T>
      *            the data provider, not null
      * @see Listing#setDataProvider(DataProvider)
      */
-    public CheckBoxGroup(String caption, DataProvider<T> dataProvider) {
+    public CheckBoxGroup(String caption, DataProvider<T, ?> dataProvider) {
         this(caption);
         setDataProvider(dataProvider);
     }
diff --git a/server/src/main/java/com/vaadin/ui/ComboBox.java b/server/src/main/java/com/vaadin/ui/ComboBox.java
index 60a229ba55..2270c1a181 100644
--- a/server/src/main/java/com/vaadin/ui/ComboBox.java
+++ b/server/src/main/java/com/vaadin/ui/ComboBox.java
@@ -158,8 +158,8 @@ public class ComboBox<T> extends AbstractSingleSelect<T> implements HasValue<T>,
     }
 
     /**
-     * Constructs a combo box with a static in-memory data provider with the given
-     * options.
+     * Constructs a combo box with a static in-memory data provider with the
+     * given options.
      *
      * @param caption
      *            the caption to show in the containing layout, null for no
@@ -180,7 +180,7 @@ public class ComboBox<T> extends AbstractSingleSelect<T> implements HasValue<T>,
      * @param dataProvider
      *            the data provider to use, not null
      */
-    public ComboBox(String caption, DataProvider<T> dataProvider) {
+    public ComboBox(String caption, DataProvider<T, ?> dataProvider) {
         this(caption);
         setDataProvider(dataProvider);
     }
diff --git a/server/src/main/java/com/vaadin/ui/ListSelect.java b/server/src/main/java/com/vaadin/ui/ListSelect.java
index e616fa2af3..00e0d9912d 100644
--- a/server/src/main/java/com/vaadin/ui/ListSelect.java
+++ b/server/src/main/java/com/vaadin/ui/ListSelect.java
@@ -61,7 +61,7 @@ public class ListSelect<T> extends AbstractMultiSelect<T> {
      * @param dataProvider
      *            the data provider, not {@code null}
      */
-    public ListSelect(String caption, DataProvider<T> dataProvider) {
+    public ListSelect(String caption, DataProvider<T, ?> dataProvider) {
         this(caption);
         setDataProvider(dataProvider);
     }
diff --git a/server/src/main/java/com/vaadin/ui/NativeSelect.java b/server/src/main/java/com/vaadin/ui/NativeSelect.java
index 2a696c75d4..46e72b02c6 100644
--- a/server/src/main/java/com/vaadin/ui/NativeSelect.java
+++ b/server/src/main/java/com/vaadin/ui/NativeSelect.java
@@ -34,12 +34,12 @@ import com.vaadin.shared.ui.nativeselect.NativeSelectState;
  * A simple drop-down select component. Represented on the client side by a
  * "native" HTML {@code <select>} element. Lacks advanced features such as lazy
  * loading, filtering, and adding new items.
- * 
+ *
  * @author Vaadin Ltd.
- * 
+ *
  * @param <T>
  *            the data item type
- * 
+ *
  * @see com.vaadin.ui.ComboBox
  */
 public class NativeSelect<T> extends AbstractSingleSelect<T>
@@ -56,7 +56,7 @@ public class NativeSelect<T> extends AbstractSingleSelect<T>
 
     /**
      * Creates a new {@code NativeSelect} with the given caption and no items.
-     * 
+     *
      * @param caption
      *            the component caption to set, null for no caption
      */
@@ -68,7 +68,7 @@ public class NativeSelect<T> extends AbstractSingleSelect<T>
     /**
      * Creates a new {@code NativeSelect} with the given caption, containing the
      * data items in the given collection.
-     * 
+     *
      * @param caption
      *            the component caption to set, null for no caption
      * @param items
@@ -82,13 +82,13 @@ public class NativeSelect<T> extends AbstractSingleSelect<T>
     /**
      * Creates a new {@code NativeSelect} with the given caption, using the
      * given {@code DataProvider} as the source of data items.
-     * 
+     *
      * @param caption
      *            the component caption to set, null for no caption
      * @param dataProvider
      *            the source of data items to use, not null
      */
-    public NativeSelect(String caption, DataProvider<T> dataProvider) {
+    public NativeSelect(String caption, DataProvider<T, ?> dataProvider) {
         this(caption);
         setDataProvider(dataProvider);
     }
diff --git a/server/src/main/java/com/vaadin/ui/RadioButtonGroup.java b/server/src/main/java/com/vaadin/ui/RadioButtonGroup.java
index 8949493d6f..13b8fedc72 100644
--- a/server/src/main/java/com/vaadin/ui/RadioButtonGroup.java
+++ b/server/src/main/java/com/vaadin/ui/RadioButtonGroup.java
@@ -77,14 +77,14 @@ public class RadioButtonGroup<T> extends AbstractSingleSelect<T>
      *            the data provider, not null
      * @see Listing#setDataProvider(DataProvider)
      */
-    public RadioButtonGroup(String caption, DataProvider<T> dataProvider) {
+    public RadioButtonGroup(String caption, DataProvider<T, ?> dataProvider) {
         this(caption);
         setDataProvider(dataProvider);
     }
 
     /**
-     * Constructs a new RadioButtonGroup with caption and DataProvider containing
-     * given items.
+     * Constructs a new RadioButtonGroup with caption and DataProvider
+     * containing given items.
      *
      * @param caption
      *            the caption text
diff --git a/server/src/main/java/com/vaadin/ui/TwinColSelect.java b/server/src/main/java/com/vaadin/ui/TwinColSelect.java
index 0858a76830..2d6b97a99a 100644
--- a/server/src/main/java/com/vaadin/ui/TwinColSelect.java
+++ b/server/src/main/java/com/vaadin/ui/TwinColSelect.java
@@ -50,14 +50,15 @@ public class TwinColSelect<T> extends AbstractMultiSelect<T> {
     }
 
     /**
-     * Constructs a new TwinColSelect with caption and data provider for options.
+     * Constructs a new TwinColSelect with caption and data provider for
+     * options.
      *
      * @param caption
      *            the caption to set, can be {@code null}
      * @param dataProvider
      *            the data provider, not {@code null}
      */
-    public TwinColSelect(String caption, DataProvider<T> dataProvider) {
+    public TwinColSelect(String caption, DataProvider<T, ?> dataProvider) {
         this(caption);
         setDataProvider(dataProvider);
     }
diff --git a/server/src/test/java/com/vaadin/server/data/AbstractDataProviderTest.java b/server/src/test/java/com/vaadin/server/data/AbstractDataProviderTest.java
index b1260b8097..db2f704e2d 100644
--- a/server/src/test/java/com/vaadin/server/data/AbstractDataProviderTest.java
+++ b/server/src/test/java/com/vaadin/server/data/AbstractDataProviderTest.java
@@ -29,14 +29,15 @@ import com.vaadin.shared.Registration;
  */
 public class AbstractDataProviderTest {
 
-    private static class TestDataProvider extends AbstractDataProvider<Object> {
+    private static class TestDataProvider
+            extends AbstractDataProvider<Object, Object> {
         @Override
-        public Stream<Object> fetch(Query t) {
+        public Stream<Object> fetch(Query<Object> t) {
             return null;
         }
 
         @Override
-        public int size(Query t) {
+        public int size(Query<Object> t) {
             return 0;
         }
 
@@ -48,7 +49,7 @@ public class AbstractDataProviderTest {
 
     @Test
     public void refreshAll_notifyListeners() {
-        AbstractDataProvider<Object> dataProvider = new TestDataProvider();
+        TestDataProvider dataProvider = new TestDataProvider();
         AtomicReference<DataChangeEvent> event = new AtomicReference<>();
         dataProvider.addDataProviderListener(ev -> {
             Assert.assertNull(event.get());
@@ -61,7 +62,7 @@ public class AbstractDataProviderTest {
 
     @Test
     public void removeListener_listenerIsNotNotified() {
-        AbstractDataProvider<Object> dataProvider = new TestDataProvider();
+        TestDataProvider dataProvider = new TestDataProvider();
         AtomicReference<DataChangeEvent> event = new AtomicReference<>();
         Registration registration = dataProvider
                 .addDataProviderListener(ev -> event.set(ev));
diff --git a/server/src/test/java/com/vaadin/server/data/provider/bov/DataProviderBoVTest.java b/server/src/test/java/com/vaadin/server/data/provider/bov/DataProviderBoVTest.java
index 2ad7fc4178..2b282a535a 100644
--- a/server/src/test/java/com/vaadin/server/data/provider/bov/DataProviderBoVTest.java
+++ b/server/src/test/java/com/vaadin/server/data/provider/bov/DataProviderBoVTest.java
@@ -22,11 +22,11 @@ import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
-import com.vaadin.server.data.BackEndDataProvider;
-import com.vaadin.server.data.DataProvider;
 import org.junit.Before;
 import org.junit.Test;
 
+import com.vaadin.server.data.BackEndDataProvider;
+import com.vaadin.server.data.DataProvider;
 import com.vaadin.server.data.SortOrder;
 import com.vaadin.shared.data.sort.SortDirection;
 
@@ -96,13 +96,13 @@ public class DataProviderBoVTest {
 
     @Test
     public void testPersons() {
-        DataProvider<Person> dataProvider = createUnsortedDataProvider();
+        DataProvider<Person, ?> dataProvider = createUnsortedDataProvider();
         // TODO test if the provider contains all defined Persons in
         // correct(unchanged) order
     }
 
-    private DataProvider<Person> createUnsortedDataProvider() {
-        DataProvider<Person> dataProvider = new BackEndDataProvider<>(
+    private DataProvider<Person, ?> createUnsortedDataProvider() {
+        DataProvider<Person, ?> dataProvider = new BackEndDataProvider<>(
                 // First callback fetches items based on a query
                 query -> {
                     // The index of the first item to load
@@ -124,13 +124,13 @@ public class DataProviderBoVTest {
     @Test
     public void testSortedPersons() {
 
-        DataProvider<Person> dataProvider = createSortedDataProvider();
+        DataProvider<Person, ?> dataProvider = createSortedDataProvider();
         // TODO test if provider contains all defined Persons in correct order
         // TODO test Query.sortOrders correctness
     }
 
-    private DataProvider<Person> createSortedDataProvider() {
-        DataProvider<Person> dataProvider = new BackEndDataProvider<>(
+    private DataProvider<Person, ?> createSortedDataProvider() {
+        DataProvider<Person, ?> dataProvider = new BackEndDataProvider<>(
                 // First callback fetches items based on a query
                 query -> {
                     List<PersonService.PersonSort> sortOrders = new ArrayList<>();
diff --git a/uitest/src/main/java/com/vaadin/tests/components/combobox/ComboBoxInvalidNullSelection.java b/uitest/src/main/java/com/vaadin/tests/components/combobox/ComboBoxInvalidNullSelection.java
index d01565e7c7..669311149c 100644
--- a/uitest/src/main/java/com/vaadin/tests/components/combobox/ComboBoxInvalidNullSelection.java
+++ b/uitest/src/main/java/com/vaadin/tests/components/combobox/ComboBoxInvalidNullSelection.java
@@ -8,9 +8,8 @@ import com.vaadin.ui.ComboBox;
 
 public class ComboBoxInvalidNullSelection extends TestBase {
 
-    private static final Object CAPTION = "C";
-    private DataProvider<String> ds1;
-    private DataProvider<String> ds2;
+    private DataProvider<String, ?> ds1;
+    private DataProvider<String, ?> ds2;
     private ComboBox<String> combo;
     private Log log = new Log(5);
 
diff --git a/uitest/src/main/java/com/vaadin/tests/components/grid/GridApplyFilterWhenScrolledDown.java b/uitest/src/main/java/com/vaadin/tests/components/grid/GridApplyFilterWhenScrolledDown.java
index b1672fbbed..8f92e431c4 100644
--- a/uitest/src/main/java/com/vaadin/tests/components/grid/GridApplyFilterWhenScrolledDown.java
+++ b/uitest/src/main/java/com/vaadin/tests/components/grid/GridApplyFilterWhenScrolledDown.java
@@ -32,7 +32,8 @@ public class GridApplyFilterWhenScrolledDown extends AbstractTestUI {
         addComponent(button);
     }
 
-    private void filter(DataProvider<String> dataProvider, List<String> data) {
+    private void filter(DataProvider<String, ?> dataProvider,
+            List<String> data) {
         String last = data.get(data.size() - 1);
         data.clear();
         data.add(last);
diff --git a/uitest/src/main/java/com/vaadin/tests/components/grid/basics/RefreshDataProvider.java b/uitest/src/main/java/com/vaadin/tests/components/grid/basics/RefreshDataProvider.java
index 288bc190f3..50021699d6 100644
--- a/uitest/src/main/java/com/vaadin/tests/components/grid/basics/RefreshDataProvider.java
+++ b/uitest/src/main/java/com/vaadin/tests/components/grid/basics/RefreshDataProvider.java
@@ -47,7 +47,8 @@ public class RefreshDataProvider extends AbstractReindeerTestUI {
         update.setId("update");
         addComponent(update);
 
-        Button add = new Button("Add data", event -> addData(dataProvider, data));
+        Button add = new Button("Add data",
+                event -> addData(dataProvider, data));
         add.setId("add");
         addComponent(add);
 
@@ -57,13 +58,13 @@ public class RefreshDataProvider extends AbstractReindeerTestUI {
         addComponent(remove);
     }
 
-    private void updateData(DataProvider<DataObject> dataProvider,
+    private void updateData(DataProvider<DataObject, ?> dataProvider,
             List<DataObject> data) {
         data.get(0).setCoordinates("Updated coordinates");
         dataProvider.refreshAll();
     }
 
-    private void addData(DataProvider<DataObject> dataProvider,
+    private void addData(DataProvider<DataObject, ?> dataProvider,
             List<DataObject> data) {
         DataObject dataObject = new DataObject();
         dataObject.setCoordinates("Added");
@@ -71,7 +72,7 @@ public class RefreshDataProvider extends AbstractReindeerTestUI {
         dataProvider.refreshAll();
     }
 
-    private void removeData(DataProvider<DataObject> dataProvider,
+    private void removeData(DataProvider<DataObject, ?> dataProvider,
             List<DataObject> data) {
         data.remove(0);
         dataProvider.refreshAll();
diff --git a/uitest/src/main/java/com/vaadin/tests/layouts/MovingComponentsWhileOldParentInvisible.java b/uitest/src/main/java/com/vaadin/tests/layouts/MovingComponentsWhileOldParentInvisible.java
index 16e131da76..2c37d1a0e0 100644
--- a/uitest/src/main/java/com/vaadin/tests/layouts/MovingComponentsWhileOldParentInvisible.java
+++ b/uitest/src/main/java/com/vaadin/tests/layouts/MovingComponentsWhileOldParentInvisible.java
@@ -53,7 +53,7 @@ public class MovingComponentsWhileOldParentInvisible extends TestBase {
         });
 
         componentContainerSelect.setValue(componentContainerSelect
-                .getDataProvider().fetch(new Query()).iterator().next());
+                .getDataProvider().fetch(new Query<>()).iterator().next());
         Button but1 = new Button("Move in and out of component container",
                 new Button.ClickListener() {
 
diff --git a/uitest/src/main/java/com/vaadin/tests/util/ItemDataProvider.java b/uitest/src/main/java/com/vaadin/tests/util/ItemDataProvider.java
index 5d207720d0..8b77f4cd2a 100644
--- a/uitest/src/main/java/com/vaadin/tests/util/ItemDataProvider.java
+++ b/uitest/src/main/java/com/vaadin/tests/util/ItemDataProvider.java
@@ -9,7 +9,7 @@ import com.vaadin.server.data.BackEndDataProvider;
  *
  * @author Vaadin Ltd
  */
-public class ItemDataProvider extends BackEndDataProvider<String> {
+public class ItemDataProvider extends BackEndDataProvider<String, Object> {
 
     public ItemDataProvider(int size) {
         super(q -> IntStream