BAEL-2411 Spring Data Jpa Pagingg and Sorting (#5912)

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/dao/repositories/product/ProductRepository.java

@@ -1,8 +1,13 @@
 package com.baeldung.dao.repositories.product;
 
 import com.baeldung.domain.product.Product;
-import org.springframework.data.jpa.repository.JpaRepository;
 
-public interface ProductRepository extends JpaRepository<Product, Integer> {
+import java.util.List;
 
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.repository.PagingAndSortingRepository;
+
+public interface ProductRepository extends PagingAndSortingRepository<Product, Integer> {
+
+    List<Product> findAllByPrice(double price, Pageable pageable);
 }

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/domain/product/Product.java

@@ -19,6 +19,17 @@ public class Product {
         super();
     }
 
+    private Product(int id, String name, double price) {
+        super();
+        this.id = id;
+        this.name = name;
+        this.price = price;
+    }
+
+    public static Product from(int id, String name, double price) {
+        return new Product(id, name, price);
+    }
+
     public int getId() {
         return id;
     }
@@ -46,7 +57,11 @@ public class Product {
     @Override
     public String toString() {
         final StringBuilder builder = new StringBuilder();
-        builder.append("Product [name=").append(name).append(", id=").append(id).append("]");
+        builder.append("Product [name=")
+            .append(name)
+            .append(", id=")
+            .append(id)
+            .append("]");
         return builder.toString();
     }
 }

persistence-modules/spring-data-jpa/src/test/java/com/baeldung/dao/repositories/product/ProductRepositoryIntegrationTest.java

@@ -0,0 +1,142 @@
+package com.baeldung.dao.repositories.product;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+import org.springframework.transaction.annotation.Transactional;
+
+import com.baeldung.config.PersistenceProductConfiguration;
+import com.baeldung.domain.product.Product;
+
+@RunWith(SpringRunner.class)
+@ContextConfiguration(classes = { PersistenceProductConfiguration.class })
+@EnableTransactionManagement
+public class ProductRepositoryIntegrationTest {
+
+    @Autowired
+    private ProductRepository productRepository;
+
+    @Before
+    @Transactional("productTransactionManager")
+    public void setUp() {
+        productRepository.save(Product.from(1001, "Book", 21));
+        productRepository.save(Product.from(1002, "Coffee", 10));
+        productRepository.save(Product.from(1003, "Jeans", 30));
+        productRepository.save(Product.from(1004, "Shirt", 32));
+        productRepository.save(Product.from(1005, "Bacon", 10));
+    }
+
+    @Test
+    public void whenRequestingFirstPageOfSizeTwo_ThenReturnFirstPage() {
+        Pageable pageRequest = PageRequest.of(0, 2);
+
+        Page<Product> result = productRepository.findAll(pageRequest);
+
+        assertThat(result.getContent(), hasSize(2));
+        assertTrue(result.stream()
+            .map(Product::getId)
+            .allMatch(id -> Arrays.asList(1001, 1002)
+                .contains(id)));
+    }
+
+    @Test
+    public void whenRequestingSecondPageOfSizeTwo_ThenReturnSecondPage() {
+        Pageable pageRequest = PageRequest.of(1, 2);
+
+        Page<Product> result = productRepository.findAll(pageRequest);
+
+        assertThat(result.getContent(), hasSize(2));
+        assertTrue(result.stream()
+            .map(Product::getId)
+            .allMatch(id -> Arrays.asList(1003, 1004)
+                .contains(id)));
+    }
+
+    @Test
+    public void whenRequestingLastPage_ThenReturnLastPageWithRemData() {
+        Pageable pageRequest = PageRequest.of(2, 2);
+
+        Page<Product> result = productRepository.findAll(pageRequest);
+
+        assertThat(result.getContent(), hasSize(1));
+        assertTrue(result.stream()
+            .map(Product::getId)
+            .allMatch(id -> Arrays.asList(1005)
+                .contains(id)));
+    }
+
+    @Test
+    public void whenSortingByNameAscAndPaging_ThenReturnSortedPagedResult() {
+        Pageable pageRequest = PageRequest.of(0, 3, Sort.by("name"));
+
+        Page<Product> result = productRepository.findAll(pageRequest);
+
+        assertThat(result.getContent(), hasSize(3));
+        assertThat(result.getContent()
+            .stream()
+            .map(Product::getId)
+            .collect(Collectors.toList()), equalTo(Arrays.asList(1005, 1001, 1002)));
+
+    }
+
+    @Test
+    public void whenSortingByPriceDescAndPaging_ThenReturnSortedPagedResult() {
+        Pageable pageRequest = PageRequest.of(0, 3, Sort.by("price")
+            .descending());
+
+        Page<Product> result = productRepository.findAll(pageRequest);
+
+        assertThat(result.getContent(), hasSize(3));
+        assertThat(result.getContent()
+            .stream()
+            .map(Product::getId)
+            .collect(Collectors.toList()), equalTo(Arrays.asList(1004, 1003, 1001)));
+
+    }
+
+    @Test
+    public void whenSortingByPriceDescAndNameAscAndPaging_ThenReturnSortedPagedResult() {
+        Pageable pageRequest = PageRequest.of(0, 5, Sort.by("price")
+            .descending()
+            .and(Sort.by("name")));
+
+        Page<Product> result = productRepository.findAll(pageRequest);
+
+        assertThat(result.getContent(), hasSize(5));
+        assertThat(result.getContent()
+            .stream()
+            .map(Product::getId)
+            .collect(Collectors.toList()), equalTo(Arrays.asList(1004, 1003, 1001, 1005, 1002)));
+
+    }
+
+    @Test
+    public void whenRequestingFirstPageOfSizeTwoUsingCustomMethod_ThenReturnFirstPage() {
+        Pageable pageRequest = PageRequest.of(0, 2);
+
+        List<Product> result = productRepository.findAllByPrice(10, pageRequest);
+
+        assertThat(result, hasSize(2));
+        assertTrue(result.stream()
+            .map(Product::getId)
+            .allMatch(id -> Arrays.asList(1002, 1005)
+                .contains(id)));
+    }
+}