DATAJPA-1594 - Revised nullability enforcement in Querydsl.

src/main/java/org/springframework/data/jpa/repository/support/Querydsl.java

@@ -91,21 +91,28 @@ public class Querydsl {
 	/**
 	 * Creates the {@link JPQLQuery} instance based on the configured {@link EntityManager}.
 	 *
+	 * @param paths must not be {@literal null}.
 	 * @return
 	 */
 	public AbstractJPAQuery<Object, JPAQuery<Object>> createQuery(EntityPath<?>... paths) {
+
+		Assert.notNull(paths, "Paths must not be null!");
+
 		return createQuery().from(paths);
 	}
 
 	/**
 	 * Applies the given {@link Pageable} to the given {@link JPQLQuery}.
 	 *
-	 * @param pageable
+	 * @param pageable must not be {@literal null}.
 	 * @param query must not be {@literal null}.
 	 * @return the Querydsl {@link JPQLQuery}.
 	 */
 	public <T> JPQLQuery<T> applyPagination(Pageable pageable, JPQLQuery<T> query) {
 
+		Assert.notNull(pageable, "Pageable must not be null!");
+		Assert.notNull(query, "JPQLQuery must not be null!");
+
 		if (pageable.isUnpaged()) {
 			return query;
 		}
@@ -119,12 +126,15 @@ public class Querydsl {
 	/**
 	 * Applies sorting to the given {@link JPQLQuery}.
 	 *
-	 * @param sort
+	 * @param sort must not be {@literal null}.
 	 * @param query must not be {@literal null}.
 	 * @return the Querydsl {@link JPQLQuery}
 	 */
 	public <T> JPQLQuery<T> applySorting(Sort sort, JPQLQuery<T> query) {
 
+		Assert.notNull(sort, "Sort must not be null!");
+		Assert.notNull(query, "Query must not be null!");
+
 		if (sort.isUnsorted()) {
 			return query;
 		}

src/main/java/org/springframework/data/jpa/repository/support/QuerydslJpaPredicateExecutor.java

@@ -87,6 +87,8 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	@Override
 	public Optional<T> findOne(Predicate predicate) {
 
+		Assert.notNull(predicate, "Predicate must not be null!");
+
 		try {
 			return Optional.ofNullable(createQuery(predicate).select(path).fetchOne());
 		} catch (NonUniqueResultException ex) {
@@ -100,6 +102,9 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	 */
 	@Override
 	public List<T> findAll(Predicate predicate) {
+
+		Assert.notNull(predicate, "Predicate must not be null!");
+
 		return createQuery(predicate).select(path).fetch();
 	}
 
@@ -109,6 +114,10 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	 */
 	@Override
 	public List<T> findAll(Predicate predicate, OrderSpecifier<?>... orders) {
+
+		Assert.notNull(predicate, "Predicate must not be null!");
+		Assert.notNull(orders, "Order specifiers must not be null!");
+
 		return executeSorted(createQuery(predicate).select(path), orders);
 	}
 
@@ -119,6 +128,7 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	@Override
 	public List<T> findAll(Predicate predicate, Sort sort) {
 
+		Assert.notNull(predicate, "Predicate must not be null!");
 		Assert.notNull(sort, "Sort must not be null!");
 
 		return executeSorted(createQuery(predicate).select(path), sort);
@@ -143,6 +153,7 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	@Override
 	public Page<T> findAll(Predicate predicate, Pageable pageable) {
 
+		Assert.notNull(predicate, "Predicate must not be null!");
 		Assert.notNull(pageable, "Pageable must not be null!");
 
 		final JPQLQuery<?> countQuery = createCountQuery(predicate);
@@ -177,8 +188,9 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	 */
 	protected JPQLQuery<?> createQuery(Predicate... predicate) {
 
-		AbstractJPAQuery<?, ?> query = doCreateQuery(getQueryHints().withFetchGraphs(entityManager), predicate);
+		Assert.notNull(predicate, "Predicate must not be null!");
 
+		AbstractJPAQuery<?, ?> query = doCreateQuery(getQueryHints().withFetchGraphs(entityManager), predicate);
 		CrudMethodMetadata metadata = getRepositoryMethodMetadata();
 
 		if (metadata == null) {
@@ -221,7 +233,8 @@ public class QuerydslJpaPredicateExecutor<T> implements QuerydslPredicateExecuto
 	 * @return
 	 */
 	private QueryHints getQueryHintsForCount() {
-		return metadata == null ? QueryHints.NoHints.INSTANCE : DefaultQueryHints.of(entityInformation, metadata).forCounts();
+		return metadata == null ? QueryHints.NoHints.INSTANCE
+				: DefaultQueryHints.of(entityInformation, metadata).forCounts();
 	}
 
 	private AbstractJPAQuery<?, ?> doCreateQuery(QueryHints hints, @Nullable Predicate... predicate) {