Polishing.

Fixed import formatting.
Removed (non-Javadoc) comment, since we don't use them anymore.
Simplified some code and removed superfluous or wrong Javadoc in touched files.
Formatting.

See #2388
Original pull request #2449

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

@@ -17,14 +17,34 @@ package org.springframework.data.jpa.repository.support;
 
 import static org.springframework.data.jpa.repository.query.QueryUtils.*;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
 import java.util.function.Function;
 
-import javax.persistence.*;
-import javax.persistence.criteria.*;
+import javax.persistence.EntityManager;
+import javax.persistence.LockModeType;
+import javax.persistence.NoResultException;
+import javax.persistence.Parameter;
+import javax.persistence.Query;
+import javax.persistence.TypedQuery;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.ParameterExpression;
+import javax.persistence.criteria.Path;
+import javax.persistence.criteria.Predicate;
+import javax.persistence.criteria.Root;
 
 import org.springframework.dao.EmptyResultDataAccessException;
-import org.springframework.data.domain.*;
+import org.springframework.data.domain.Example;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageImpl;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
 import org.springframework.data.jpa.convert.QueryByExamplePredicateBuilder;
 import org.springframework.data.jpa.domain.Specification;
 import org.springframework.data.jpa.provider.PersistenceProvider;
@@ -307,7 +327,6 @@ public class SimpleJpaRepository<T, ID> implements JpaRepositoryImplementation<T
 	/**
 	 * Returns {@link QueryHints} with the query hints based on the current {@link CrudMethodMetadata} and potential
 	 * {@link EntityGraph} information.
-	 *
 	 */
 	protected QueryHints getQueryHints() {
 		return metadata == null ? NoHints.INSTANCE : DefaultQueryHints.of(entityInformation, metadata);
@@ -537,10 +556,6 @@ public class SimpleJpaRepository<T, ID> implements JpaRepositoryImplementation<T
 		return query.setMaxResults(1).getResultList().size() == 1;
 	}
 
-	/*
-	 * (non-Javadoc)
-	 * @see org.springframework.data.jpa.repository.JpaSpecificationExecutor#exists(org.springframework.data.jpa.domain.Specification)
-	 */
 	@Override
 	public boolean exists(Specification<T> spec) {
 
@@ -567,8 +582,7 @@ public class SimpleJpaRepository<T, ID> implements JpaRepositoryImplementation<T
 	 */
 	@Override
 	public <S extends T> List<S> findAll(Example<S> example, Sort sort) {
-		return getQuery(new ExampleSpecification<>(example, escapeCharacter), example.getProbeType(), sort)
-				.getResultList();
+		return getQuery(new ExampleSpecification<>(example, escapeCharacter), example.getProbeType(), sort).getResultList();
 	}
 
 	/*

src/test/java/org/springframework/data/jpa/domain/sample/UserSpecifications.java

@@ -32,9 +32,6 @@ public class UserSpecifications {
 
 	/**
 	 * A {@link Specification} to match on a {@link User}'s firstname.
-	 *
-	 * @param firstname
-	 * @return
 	 */
 	public static Specification<User> userHasFirstname(final String firstname) {
 
@@ -43,9 +40,6 @@ public class UserSpecifications {
 
 	/**
 	 * A {@link Specification} to match on a {@link User}'s lastname.
-	 *
-	 * @param firstname
-	 * @return
 	 */
 	public static Specification<User> userHasLastname(final String lastname) {
 
@@ -54,27 +48,16 @@ public class UserSpecifications {
 
 	/**
 	 * A {@link Specification} to do a like-match on a {@link User}'s firstname.
-	 *
-	 * @param firstname
-	 * @return
 	 */
 	public static Specification<User> userHasFirstnameLike(final String expression) {
 
-		return new Specification<User>() {
-
-			@Override
-			public Predicate toPredicate(Root<User> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
-
-				return cb.like(root.get("firstname").as(String.class), String.format("%%%s%%", expression));
-			}
-		};
+		return (root, query, cb) -> cb.like(root.get("firstname").as(String.class), String.format("%%%s%%", expression));
 	}
 
 	/**
 	 * A {@link Specification} to do an age check.
 	 *
 	 * @param age upper (exclusive) bound of the age
-	 * @return
 	 */
 	public static Specification<User> userHasAgeLess(final Integer age) {
 
@@ -84,33 +67,19 @@ public class UserSpecifications {
 	/**
 	 * A {@link Specification} to do a like-match on a {@link User}'s lastname but also adding a sort order on the
 	 * firstname.
-	 *
-	 * @param firstname
-	 * @return
 	 */
 	public static Specification<User> userHasLastnameLikeWithSort(final String expression) {
 
-		return new Specification<User>() {
+		return (root, query, cb) -> {
 
-			@Override
-			public Predicate toPredicate(Root<User> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
+			query.orderBy(cb.asc(root.get("firstname")));
 
-				query.orderBy(cb.asc(root.get("firstname")));
-
-				return cb.like(root.get("lastname").as(String.class), String.format("%%%s%%", expression));
-			}
+			return cb.like(root.get("lastname").as(String.class), String.format("%%%s%%", expression));
 		};
 	}
 
 	private static <T> Specification<T> simplePropertySpec(final String property, final Object value) {
 
-		return new Specification<T>() {
-
-			@Override
-			public Predicate toPredicate(Root<T> root, CriteriaQuery<?> query, CriteriaBuilder builder) {
-
-				return builder.equal(root.get(property), value);
-			}
-		};
+		return (root, query, builder) -> builder.equal(root.get(property), value);
 	}
 }

src/test/java/org/springframework/data/jpa/repository/UserRepositoryTests.java

@@ -2643,6 +2643,7 @@ public class UserRepositoryTests {
 
 	@Test // GH-2388
 	void existsWithSpec() {
+
 		flushTestUsers();
 
 		Specification<User> minorSpec = userHasAgeLess(18);