diff --git a/jpa/example/src/main/java/example/springdata/jpa/pagination/Book.java b/jpa/example/src/main/java/example/springdata/jpa/pagination/Book.java index 7d78c48e..9d6906d7 100644 --- a/jpa/example/src/main/java/example/springdata/jpa/pagination/Book.java +++ b/jpa/example/src/main/java/example/springdata/jpa/pagination/Book.java @@ -15,14 +15,14 @@ */ package example.springdata.jpa.pagination; -import java.util.Date; - import jakarta.persistence.Entity; import jakarta.persistence.Id; import jakarta.persistence.ManyToOne; import jakarta.persistence.Table; import lombok.Data; +import java.util.Date; + /** * @author Christoph Strobl */ @@ -31,12 +31,10 @@ import lombok.Data; @Table(name = "books") public class Book { - @Id - private String id; + @Id private String id; private String title; private String isbn10; private Date publicationDate; - @ManyToOne - Author author; + @ManyToOne Author author; } diff --git a/jpa/example/src/main/java/example/springdata/jpa/pagination/BookRepository.java b/jpa/example/src/main/java/example/springdata/jpa/pagination/BookRepository.java index 53dbde8a..67df6d2e 100644 --- a/jpa/example/src/main/java/example/springdata/jpa/pagination/BookRepository.java +++ b/jpa/example/src/main/java/example/springdata/jpa/pagination/BookRepository.java @@ -28,9 +28,10 @@ import org.springframework.data.repository.ListCrudRepository; public interface BookRepository extends ListCrudRepository { /** - * Uses an {@literal offset} based pagination that first sorts the entries by their {@link Book#getPublicationDate() publication_date} - * and then limits the result by dropping the number of rows specified in the {@link Pageable#getOffset() offset} clause. - * To retrieve {@link Page#getTotalElements()} an additional count query is executed. + * Uses an {@literal offset} based pagination that first sorts the entries by their {@link Book#getPublicationDate() + * publication_date} and then limits the result by dropping the number of rows specified in the + * {@link Pageable#getOffset() offset} clause. To retrieve {@link Page#getTotalElements()} an additional count query + * is executed. * * @param title * @param pageable @@ -39,8 +40,9 @@ public interface BookRepository extends ListCrudRepository { Page findByTitleContainsOrderByPublicationDate(String title, Pageable pageable); /** - * Uses an {@literal offset} based slicing that first sorts the entries by their {@link Book#getPublicationDate() publication_date} - * and then limits the result by dropping the number of rows specified in the {@link Pageable#getOffset() offset} clause. + * Uses an {@literal offset} based slicing that first sorts the entries by their {@link Book#getPublicationDate() + * publication_date} and then limits the result by dropping the number of rows specified in the + * {@link Pageable#getOffset() offset} clause. * * @param title * @param pageable @@ -49,11 +51,10 @@ public interface BookRepository extends ListCrudRepository { Slice findBooksByTitleContainsOrderByPublicationDate(String title, Pageable pageable); /** - * Depending on the provided {@link ScrollPosition} either {@link org.springframework.data.domain.OffsetScrollPosition offset} - * or {@link org.springframework.data.domain.KeysetScrollPosition keyset} scrolling is possible. - * Scrolling through results requires a stable {@link org.springframework.data.domain.Sort} which is different from - * what {@link Pageable#getSort()} offers. - * The {@literal limit} is defined via the {@literal Top} keyword. + * Depending on the provided {@link ScrollPosition} either {@link org.springframework.data.domain.OffsetScrollPosition + * offset} or {@link org.springframework.data.domain.KeysetScrollPosition keyset} scrolling is possible. Scrolling + * through results requires a stable {@link org.springframework.data.domain.Sort} which is different from what + * {@link Pageable#getSort()} offers. The {@literal limit} is defined via the {@literal Top} keyword. * * @param title * @param scrollPosition diff --git a/jpa/example/src/main/java/example/springdata/jpa/pagination/PagingRepoConfig.java b/jpa/example/src/main/java/example/springdata/jpa/pagination/PagingRepoConfig.java index d6b4ec99..77930330 100644 --- a/jpa/example/src/main/java/example/springdata/jpa/pagination/PagingRepoConfig.java +++ b/jpa/example/src/main/java/example/springdata/jpa/pagination/PagingRepoConfig.java @@ -22,7 +22,5 @@ import org.springframework.data.jpa.repository.config.EnableJpaRepositories; * @author Christoph Strobl */ @SpringBootApplication -@EnableJpaRepositories(repositoryBaseClass = BookRepository.class) -class PagingRepoConfig { - -} +@EnableJpaRepositories(basePackageClasses = BookRepository.class) +class PagingRepoConfig {} diff --git a/jpa/example/src/test/java/example/springdata/jpa/pagination/PaginationTests.java b/jpa/example/src/test/java/example/springdata/jpa/pagination/PaginationTests.java index 70ba81f8..6191db91 100644 --- a/jpa/example/src/test/java/example/springdata/jpa/pagination/PaginationTests.java +++ b/jpa/example/src/test/java/example/springdata/jpa/pagination/PaginationTests.java @@ -15,7 +15,9 @@ */ package example.springdata.jpa.pagination; -import static org.assertj.core.api.AssertionsForClassTypes.*; +import static org.assertj.core.api.Assertions.*; + +import jakarta.persistence.EntityManager; import java.util.List; import java.util.Random; @@ -24,13 +26,12 @@ import java.util.concurrent.TimeUnit; import java.util.stream.Collectors; import java.util.stream.IntStream; -import com.github.javafaker.Faker; -import jakarta.persistence.EntityManager; import org.junit.jupiter.api.BeforeEach; import org.junit.jupiter.api.Test; + import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; -import org.springframework.boot.test.context.SpringBootTest; +import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest; import org.springframework.context.annotation.Configuration; import org.springframework.data.domain.KeysetScrollPosition; import org.springframework.data.domain.OffsetScrollPosition; @@ -40,15 +41,18 @@ import org.springframework.data.domain.Pageable; import org.springframework.data.domain.ScrollPosition; import org.springframework.data.domain.Slice; import org.springframework.data.domain.Window; -import org.springframework.transaction.annotation.Transactional; +import org.springframework.data.domain.WindowIterator; +import org.springframework.data.util.Streamable; + +import com.github.javafaker.Faker; /** - * Show different types of paging styles using {@link Page}, {@link org.springframework.data.domain.Slice} and {@link Window} + * Show different types of paging styles using {@link Page}, {@link Slice} and {@link Window}. * * @author Christoph Strobl + * @author Mark Paluch */ -@SpringBootTest -@Transactional +@DataJpaTest class PaginationTests { @Configuration @@ -57,8 +61,7 @@ class PaginationTests { } - @Autowired - BookRepository books; + @Autowired BookRepository books; @BeforeEach void setUp() { @@ -71,10 +74,9 @@ class PaginationTests { } /** - * Page through the results using an offset/limit approach where the server skips over the number of results - * specified via {@link Pageable#getOffset()}. - * The {@link Page} return type will run an additional {@literal count} query to read the total number of matching rows - * on each request. + * Page through the results using an offset/limit approach where the server skips over the number of results specified + * via {@link Pageable#getOffset()}. The {@link Page} return type will run an additional {@literal count} query to + * read the total number of matching rows on each request. */ @Test void pageThroughResultsWithSkipAndLimit() { @@ -93,9 +95,9 @@ class PaginationTests { /** * Run through the results using an offset/limit approach where the server skips over the number of results specified - * via {@link Pageable#getOffset()}. - * No additional {@literal count} query to read the total number of matching rows is issued. Still {@link Slice} requests, - * but does not emit, one row more than specified via {@link Page#getSize()} to feed {@link Slice#hasNext()} + * via {@link Pageable#getOffset()}. No additional {@literal count} query to read the total number of matching rows is + * issued. Still {@link Slice} requests, but does not emit, one row more than specified via {@link Page#getSize()} to + * feed {@link Slice#hasNext()} */ @Test void sliceThroughResultsWithSkipAndLimit() { @@ -133,11 +135,28 @@ class PaginationTests { } while (window.hasNext()); } + /** + * Scroll through the results using an offset/limit approach where the server skips over the number of results + * specified via {@link OffsetScrollPosition#getOffset()} using {@link WindowIterator}. + *

+ * This approach is similar to the {@link #sliceThroughResultsWithSkipAndLimit() slicing one}. + */ + @Test + void scrollThroughResultsUsingWindowIteratorWithSkipAndLimit() { + + WindowIterator iterator = WindowIterator + .of(scrollPosition -> books.findTop2ByTitleContainsOrderByPublicationDate("the-crazy-book-", scrollPosition)) + .startingAt(OffsetScrollPosition.initial()); + + List allBooks = Streamable.of(() -> iterator).stream().toList(); + assertThat(allBooks).hasSize(50); + } + /** * Scroll through the results using an index based approach where the {@link KeysetScrollPosition#getKeys() keyset} * keeps track of already seen values to resume scrolling by altering the where clause to only return rows after the - * values contained in the keyset. - * Set {@literal logging.level.org.hibernate.SQL=debug} to show the modified query in the log. + * values contained in the keyset. Set {@literal logging.level.org.hibernate.SQL=debug} to show the modified query in + * the log. */ @Test void scrollThroughResultsWithKeyset() { @@ -155,8 +174,7 @@ class PaginationTests { // --> Test Data - @Autowired - EntityManager em; + @Autowired EntityManager em; private List createAuthors(Faker faker) { @@ -176,18 +194,17 @@ class PaginationTests { private List createBooks(Faker faker, List authors) { Random rand = new Random(); - return IntStream.range(0, 100) - .mapToObj(id -> { + return IntStream.range(0, 100).mapToObj(id -> { - Book book = new Book(); - book.setId("book-%03d".formatted(id)); - book.setTitle(faker.book().title()); - book.setIsbn10(UUID.randomUUID().toString().substring(0, 10)); - book.setPublicationDate(faker.date().past(5000, TimeUnit.DAYS)); - book.setAuthor(authors.get(rand.nextInt(authors.size()))); + Book book = new Book(); + book.setId("book-%03d".formatted(id)); + book.setTitle((id % 2 == 0 ? "the-crazy-book-" : "") + faker.book().title()); + book.setIsbn10(UUID.randomUUID().toString().substring(0, 10)); + book.setPublicationDate(faker.date().past(5000, TimeUnit.DAYS)); + book.setAuthor(authors.get(rand.nextInt(authors.size()))); - em.persist(book); - return book; - }).collect(Collectors.toList()); + em.persist(book); + return book; + }).collect(Collectors.toList()); } }