DATACMNS-1673 - Polishing.

Use method references where possible. Cleanup generics. Omit superfluous calls.

Original pull request: #426.

src/main/java/org/springframework/data/mapping/model/BasicPersistentEntity.java

@@ -278,9 +278,7 @@ public class BasicPersistentEntity<T, P extends PersistentProperty<P>> implement
 
 		Assert.notNull(association, "Association must not be null!");
 
-		if (!associations.contains(association)) {
-			associations.add(association);
-		}
+		associations.add(association);
 	}
 
 	/*

src/main/java/org/springframework/data/repository/core/support/MethodInvocationValidator.java

@@ -111,13 +111,13 @@ public class MethodInvocationValidator implements MethodInterceptor {
 
 		boolean nullableReturn;
 		boolean[] nullableParameters;
-		MethodParameter methodParameters[];
+		MethodParameter[] methodParameters;
 
 		static Nullability of(Method method, ParameterNameDiscoverer discoverer) {
 
 			boolean nullableReturn = isNullableParameter(new MethodParameter(method, -1));
 			boolean[] nullableParameters = new boolean[method.getParameterCount()];
-			MethodParameter methodParameters[] = new MethodParameter[method.getParameterCount()];
+			MethodParameter[] methodParameters = new MethodParameter[method.getParameterCount()];
 
 			for (int i = 0; i < method.getParameterCount(); i++) {
 

src/main/java/org/springframework/data/repository/support/ReflectionRepositoryInvoker.java

@@ -178,7 +178,7 @@ class ReflectionRepositoryInvoker implements RepositoryInvoker {
 	 * @see org.springframework.data.rest.core.invoke.RepositoryInvoker#invokeQueryMethod(java.lang.reflect.Method, java.util.Map, org.springframework.data.domain.Pageable, org.springframework.data.domain.Sort)
 	 */
 	@Override
-	public Optional<Object> invokeQueryMethod(Method method, MultiValueMap<String, ? extends Object> parameters,
+	public Optional<Object> invokeQueryMethod(Method method, MultiValueMap<String, ?> parameters,
 			Pageable pageable, Sort sort) {
 
 		Assert.notNull(method, "Method must not be null!");
@@ -191,7 +191,7 @@ class ReflectionRepositoryInvoker implements RepositoryInvoker {
 		return returnAsOptional(invoke(method, prepareParameters(method, parameters, pageable, sort)));
 	}
 
-	private Object[] prepareParameters(Method method, MultiValueMap<String, ? extends Object> rawParameters,
+	private Object[] prepareParameters(Method method, MultiValueMap<String, ?> rawParameters,
 			Pageable pageable, Sort sort) {
 
 		List<MethodParameter> parameters = new MethodParameters(method, Optional.of(PARAM_ANNOTATION)).getParameters();