Fix Querydsl Nullability annotations.

Closes #2044

src/main/java/org/springframework/data/querydsl/binding/MultiValueBinding.java

@@ -38,7 +38,7 @@ public interface MultiValueBinding<T extends Path<? extends S>, S> {
 	 *
 	 * @param path {@link Path} to the property. Will not be {@literal null}.
 	 * @param value the value that should be bound. Will not be {@literal null} or empty.
-	 * @return can be {@literal null}, in which case the binding will not be incorporated in the overall
+	 * @return can be {@link Optional#empty()}, in which case the binding will not be incorporated in the overall
 	 *         {@link Predicate}.
 	 */
 	Optional<Predicate> bind(T path, Collection<? extends S> value);

src/main/java/org/springframework/data/querydsl/binding/OptionalValueBinding.java

@@ -33,12 +33,12 @@ public interface OptionalValueBinding<T extends Path<? extends S>, S> {
 
 	/**
 	 * Returns the predicate to be applied to the given {@link Path} for the given value. The given value will be the
-	 * first the first one provided for the given path and converted into the expected type.
+	 * first one provided for the given path and converted into the expected type.
 	 *
 	 * @param path {@link Path} to the property. Will not be {@literal null}.
 	 * @param value the value that should be bound. Will not be {@literal null}.
-	 * @return can be {@literal null}, in which case the binding will not be incorporated in the overall {@link Predicate}
-	 *         .
+	 * @return can be {@link Optional#empty()}, in which case the binding will not be incorporated in the overall
+	 *         {@link Predicate} .
 	 */
 	Optional<Predicate> bind(T path, Optional<? extends S> value);
 }

src/main/java/org/springframework/data/querydsl/binding/PathInformation.java

@@ -78,8 +78,7 @@ interface PathInformation {
 	/**
 	 * Tries to reify a Querydsl {@link Path} from the given {@link PropertyPath} and base.
 	 *
-	 * @param path must not be {@literal null}.
-	 * @param base can be {@literal null}.
+	 * @param resolver must not be {@literal null}.
 	 * @return
 	 */
 	Path<?> reifyPath(EntityPathResolver resolver);

src/main/java/org/springframework/data/querydsl/binding/SingleValueBinding.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.querydsl.binding;
 
+import org.springframework.lang.Nullable;
+
 import com.querydsl.core.types.Path;
 import com.querydsl.core.types.Predicate;
 
@@ -31,12 +33,13 @@ public interface SingleValueBinding<T extends Path<? extends S>, S> {
 
 	/**
 	 * Returns the predicate to be applied to the given {@link Path} for the given value. The given value will be the
-	 * first the first one provided for the given path and converted into the expected type.
+	 * first one provided for the given path and converted into the expected type.
 	 *
 	 * @param path {@link Path} to the property. Will not be {@literal null}.
 	 * @param value the value that should be bound. Will not be {@literal null}.
-	 * @return can be {@literal null}, in which case the binding will not be incorporated in the overall {@link Predicate}
-	 *         .
+	 * @return can be {@literal null}, in which case the binding will not be incorporated in the overall
+	 *         {@link Predicate}.
 	 */
+	@Nullable
 	Predicate bind(T path, S value);
 }