Ensure all BeanBinding chaining methods return BeanBinding

Change-Id: Ifbd5f278c83fcadbe6cf21d6c1f40914b35c4aba

server/src/main/java/com/vaadin/data/BeanBinder.java

@@ -40,6 +40,7 @@ import com.vaadin.data.validator.BeanValidator;
 import com.vaadin.server.SerializableBiConsumer;
 import com.vaadin.server.SerializableFunction;
 import com.vaadin.server.SerializablePredicate;
+import com.vaadin.ui.Label;
 import com.vaadin.util.ReflectTools;
 
 /**
@@ -79,6 +80,32 @@ public class BeanBinder<BEAN> extends Binder<BEAN> {
                     predicate, message);
         }
 
+        @Override
+        default BeanBinding<BEAN, TARGET> withValidator(
+                SerializablePredicate<? super TARGET> predicate,
+                ErrorMessageProvider errorMessageProvider) {
+            return (BeanBinding<BEAN, TARGET>) Binding.super.withValidator(
+                    predicate, errorMessageProvider);
+        }
+
+        @Override
+        default BeanBinding<BEAN, TARGET> withNullRepresentation(
+                TARGET nullRepresentation) {
+            return (BeanBinding<BEAN, TARGET>) Binding.super.withNullRepresentation(
+                    nullRepresentation);
+        }
+
+        @Override
+        public BeanBinding<BEAN, TARGET> setRequired(
+                ErrorMessageProvider errorMessageProvider);
+
+        @Override
+        public default BeanBinding<BEAN, TARGET> setRequired(
+                String errorMessage) {
+            return (BeanBinding<BEAN, TARGET>) Binding.super.setRequired(
+                    errorMessage);
+        }
+
         @Override
         public <NEWTARGET> BeanBinding<BEAN, NEWTARGET> withConverter(
                 Converter<TARGET, NEWTARGET> converter);
@@ -100,6 +127,16 @@ public class BeanBinder<BEAN> extends Binder<BEAN> {
                     toModel, toPresentation, errorMessage);
         }
 
+        @Override
+        public BeanBinding<BEAN, TARGET> withValidationStatusHandler(
+                ValidationStatusHandler handler);
+
+        @Override
+        public default BeanBinding<BEAN, TARGET> withStatusLabel(Label label) {
+            return (BeanBinding<BEAN, TARGET>) Binding.super.withStatusLabel(
+                    label);
+        }
+
         /**
          * Completes this binding by connecting the field to the property with
          * the given name. The getter and setter methods of the property are
@@ -175,6 +212,20 @@ public class BeanBinder<BEAN> extends Binder<BEAN> {
                     converter);
         }
 
+        @Override
+        public BeanBinding<BEAN, TARGET> withValidationStatusHandler(
+                ValidationStatusHandler handler) {
+            return (BeanBinding<BEAN, TARGET>) super.withValidationStatusHandler(
+                    handler);
+        }
+
+        @Override
+        public BeanBinding<BEAN, TARGET> setRequired(
+                ErrorMessageProvider errorMessageProvider) {
+            return (BeanBinding<BEAN, TARGET>) super.setRequired(
+                    errorMessageProvider);
+        }
+
         @Override
         public void bind(String propertyName) {
             checkUnbound();

server/src/test/java/com/vaadin/data/BeanBinderTest.java

@@ -3,11 +3,15 @@ package com.vaadin.data;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
 
+import java.lang.reflect.Method;
 import java.util.List;
 
+import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 
+import com.vaadin.data.BeanBinder.BeanBinding;
+import com.vaadin.data.Binder.Binding;
 import com.vaadin.tests.data.bean.BeanToValidate;
 
 public class BeanBinderTest
@@ -171,4 +175,24 @@ public class BeanBinderTest
         assertSame(field, errors.get(0).getField());
         assertEquals(message, errors.get(0).getMessage().get());
     }
+
+    @Test
+    public void beanBindingChainingMethods() {
+        Method[] methods = BeanBinding.class.getMethods();
+        for (int i = 0; i < methods.length; i++) {
+            Method method = methods[i];
+            try {
+                Method actualMethod = BeanBinding.class.getMethod(
+                        method.getName(), method.getParameterTypes());
+
+                Assert.assertNotSame(
+                        actualMethod + " should be overridden in "
+                                + BeanBinding.class
+                                + " with more specific return type ",
+                        Binding.class, actualMethod.getReturnType());
+            } catch (NoSuchMethodException | SecurityException e) {
+                throw new RuntimeException(e);
+            }
+        }
+    }
 }