JAVA-66: New module spring-data-jpa-query

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/Application.java

@@ -0,0 +1,13 @@
+package com.baeldung;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/aggregation/model/Comment.java

@@ -0,0 +1,85 @@
+package com.baeldung.aggregation.model;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+import java.util.Objects;
+
+@Entity
+public class Comment {
+    @Id
+    private Integer id;
+    private Integer year;
+    private boolean approved;
+    private String content;
+    @ManyToOne
+    private Post post;
+
+    public Comment() {
+    }
+
+    public Comment(int id, int year, boolean approved, String content, Post post) {
+        this.id = id;
+        this.year = year;
+        this.approved = approved;
+        this.content = content;
+        this.post = post;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public Integer getYear() {
+        return year;
+    }
+
+    public void setYear(Integer year) {
+        this.year = year;
+    }
+
+    public boolean isApproved() {
+        return approved;
+    }
+
+    public void setApproved(boolean approved) {
+        this.approved = approved;
+    }
+
+    public String getContent() {
+        return content;
+    }
+
+    public void setContent(String content) {
+        this.content = content;
+    }
+
+    public Post getPost() {
+        return post;
+    }
+
+    public void setPost(Post post) {
+        this.post = post;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof Comment)) {
+            return false;
+        }
+        Comment comment = (Comment) o;
+        return getId().equals(comment.getId());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getId());
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/aggregation/model/Post.java

@@ -0,0 +1,75 @@
+package com.baeldung.aggregation.model;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import java.util.List;
+import java.util.Objects;
+
+@Entity
+public class Post {
+    @Id
+    private Integer id;
+    private String title;
+    private String content;
+    @OneToMany(mappedBy = "post")
+    private List<Comment> comments;
+
+    public Post() {
+    }
+
+    public Post(Integer id, String title, String content) {
+        this.id = id;
+        this.title = title;
+        this.content = content;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getContent() {
+        return content;
+    }
+
+    public void setContent(String content) {
+        this.content = content;
+    }
+
+    public List<Comment> getComments() {
+        return comments;
+    }
+
+    public void setComments(List<Comment> comments) {
+        this.comments = comments;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof Post)) {
+            return false;
+        }
+        Post post = (Post) o;
+        return getId().equals(post.getId());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getId());
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/aggregation/model/custom/CommentCount.java

@@ -0,0 +1,27 @@
+package com.baeldung.aggregation.model.custom;
+
+public class CommentCount {
+    private Integer year;
+    private Long total;
+
+    public CommentCount(Integer year, Long total) {
+        this.year = year;
+        this.total = total;
+    }
+
+    public Integer getYear() {
+        return year;
+    }
+
+    public void setYear(Integer year) {
+        this.year = year;
+    }
+
+    public Long getTotal() {
+        return total;
+    }
+
+    public void setTotal(Long total) {
+        this.total = total;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/aggregation/model/custom/ICommentCount.java

@@ -0,0 +1,8 @@
+package com.baeldung.aggregation.model.custom;
+
+public interface ICommentCount {
+
+    Integer getYearComment();
+
+    Long getTotalComment();
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/aggregation/repository/CommentRepository.java

@@ -0,0 +1,27 @@
+package com.baeldung.aggregation.repository;
+
+import com.baeldung.aggregation.model.Comment;
+import com.baeldung.aggregation.model.custom.CommentCount;
+import com.baeldung.aggregation.model.custom.ICommentCount;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.stereotype.Repository;
+
+import java.util.List;
+
+@Repository
+public interface CommentRepository extends JpaRepository<Comment, Integer> {
+
+    @Query("SELECT c.year, COUNT(c.year) FROM Comment AS c GROUP BY c.year ORDER BY c.year DESC")
+    List<Object[]> countTotalCommentsByYear();
+
+    @Query("SELECT new com.baeldung.aggregation.model.custom.CommentCount(c.year, COUNT(c.year)) FROM Comment AS c GROUP BY c.year ORDER BY c.year DESC")
+    List<CommentCount> countTotalCommentsByYearClass();
+
+    @Query("SELECT c.year AS yearComment, COUNT(c.year) AS totalComment FROM Comment AS c GROUP BY c.year ORDER BY c.year DESC")
+    List<ICommentCount> countTotalCommentsByYearInterface();
+
+    @Query(value = "SELECT c.year AS yearComment, COUNT(c.*) AS totalComment FROM comment AS c GROUP BY c.year ORDER BY c.year DESC", nativeQuery = true)
+    List<ICommentCount> countTotalCommentsByYearNative();
+
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/boot/daos/ArticleRepository.java

@@ -0,0 +1,23 @@
+package com.baeldung.boot.daos;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import com.baeldung.boot.domain.Article;
+
+import java.util.Date;
+import java.util.List;
+
+public interface ArticleRepository extends JpaRepository<Article, Integer> {
+
+    List<Article> findAllByPublicationDate(Date publicationDate);
+
+    List<Article> findAllByPublicationTimeBetween(Date publicationTimeStart,
+                                                  Date publicationTimeEnd);
+
+    @Query("select a from Article a where a.creationDateTime <= :creationDateTime")
+    List<Article> findAllWithCreationDateTimeBefore(
+      @Param("creationDateTime") Date creationDateTime);
+
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/boot/domain/Article.java

@@ -0,0 +1,23 @@
+package com.baeldung.boot.domain;
+
+import javax.persistence.*;
+import java.util.Date;
+
+@Entity
+public class Article {
+
+    @Id
+    @GeneratedValue
+    private Integer id;
+    @Temporal(TemporalType.DATE)
+    private Date publicationDate;
+    @Temporal(TemporalType.TIME)
+    private Date publicationTime;
+    @Temporal(TemporalType.TIMESTAMP)
+    private Date creationDateTime;
+
+    public Integer getId() {
+        return id;
+    }
+
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/boot/passenger/CustomPassengerRepository.java

@@ -0,0 +1,8 @@
+package com.baeldung.boot.passenger;
+
+import java.util.List;
+
+interface CustomPassengerRepository {
+
+    List<Passenger> findOrderedBySeatNumberLimitedTo(int limit);
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/boot/passenger/Passenger.java

@@ -0,0 +1,82 @@
+package com.baeldung.boot.passenger;
+
+import javax.persistence.Basic;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import java.util.Objects;
+
+@Entity
+class Passenger {
+
+    @Id
+    @GeneratedValue
+    @Column(nullable = false)
+    private Long id;
+
+    @Basic(optional = false)
+    @Column(nullable = false)
+    private String firstName;
+
+    @Basic(optional = false)
+    @Column(nullable = false)
+    private String lastName;
+
+    @Basic(optional = false)
+    @Column(nullable = false)
+    private Integer seatNumber;
+
+    private Passenger(String firstName, String lastName, Integer seatNumber) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+        this.seatNumber = seatNumber;
+    }
+
+    static Passenger from(String firstName, String lastName, Integer seatNumber) {
+        return new Passenger(firstName, lastName, seatNumber);
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (this == object)
+            return true;
+        if (object == null || getClass() != object.getClass())
+            return false;
+        Passenger passenger = (Passenger) object;
+        return getSeatNumber() == passenger.getSeatNumber() && Objects.equals(getFirstName(), passenger.getFirstName())
+          && Objects.equals(getLastName(), passenger.getLastName());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getFirstName(), getLastName(), getSeatNumber());
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder toStringBuilder = new StringBuilder(getClass().getSimpleName());
+        toStringBuilder.append("{ id=").append(id);
+        toStringBuilder.append(", firstName='").append(firstName).append('\'');
+        toStringBuilder.append(", lastName='").append(lastName).append('\'');
+        toStringBuilder.append(", seatNumber=").append(seatNumber);
+        toStringBuilder.append('}');
+        return toStringBuilder.toString();
+    }
+
+    Long getId() {
+        return id;
+    }
+
+    String getFirstName() {
+        return firstName;
+    }
+
+    String getLastName() {
+        return lastName;
+    }
+
+    Integer getSeatNumber() {
+        return seatNumber;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/boot/passenger/PassengerRepository.java

@@ -0,0 +1,22 @@
+package com.baeldung.boot.passenger;
+
+import java.util.List;
+
+import org.springframework.data.domain.Sort;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+interface PassengerRepository extends JpaRepository<Passenger, Long>, CustomPassengerRepository {
+
+    Passenger findFirstByOrderBySeatNumberAsc();
+
+    Passenger findTopByOrderBySeatNumberAsc();
+
+    List<Passenger> findByOrderBySeatNumberAsc();
+
+    List<Passenger> findByFirstNameIgnoreCase(String firstName);
+
+    List<Passenger> findByLastNameOrderBySeatNumberAsc(String lastName);
+
+    List<Passenger> findByLastName(String lastName, Sort sort);
+
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/boot/passenger/PassengerRepositoryImpl.java

@@ -0,0 +1,20 @@
+package com.baeldung.boot.passenger;
+
+import org.springframework.stereotype.Repository;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import java.util.List;
+
+@Repository
+class PassengerRepositoryImpl implements CustomPassengerRepository {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+
+    @Override
+    public List<Passenger> findOrderedBySeatNumberLimitedTo(int limit) {
+        return entityManager.createQuery("SELECT p FROM Passenger p ORDER BY p.seatNumber",
+          Passenger.class).setMaxResults(limit).getResultList();
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/entitygraph/model/Characteristic.java

@@ -0,0 +1,43 @@
+package com.baeldung.entitygraph.model;
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+
+@Entity
+public class Characteristic {
+
+    @Id
+    private Long id;
+    private String type;
+    
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn
+    private Item item;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public Item getItem() {
+        return item;
+    }
+
+    public void setItem(Item item) {
+        this.item = item;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/entitygraph/model/Item.java

@@ -0,0 +1,48 @@
+package com.baeldung.entitygraph.model;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.NamedAttributeNode;
+import javax.persistence.NamedEntityGraph;
+import javax.persistence.OneToMany;
+
+@Entity
+@NamedEntityGraph(name = "Item.characteristics",
+    attributeNodes = @NamedAttributeNode("characteristics")
+)
+public class Item {
+
+    @Id
+    private Long id;
+    private String name;
+    
+    @OneToMany(mappedBy = "item")
+    private List<Characteristic> characteristics = new ArrayList<>();
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public List<Characteristic> getCharacteristics() {
+        return characteristics;
+    }
+
+    public void setCharacteristics(List<Characteristic> characteristics) {
+        this.characteristics = characteristics;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/entitygraph/repository/CharacteristicsRepository.java

@@ -0,0 +1,13 @@
+package com.baeldung.entitygraph.repository;
+
+import org.springframework.data.jpa.repository.EntityGraph;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import com.baeldung.entitygraph.model.Characteristic;
+
+public interface CharacteristicsRepository extends JpaRepository<Characteristic, Long> {
+    
+    @EntityGraph(attributePaths = {"item"})
+    Characteristic findByType(String type);    
+    
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/entitygraph/repository/ItemRepository.java

@@ -0,0 +1,13 @@
+package com.baeldung.entitygraph.repository;
+
+import org.springframework.data.jpa.repository.EntityGraph;
+import org.springframework.data.jpa.repository.EntityGraph.EntityGraphType;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import com.baeldung.entitygraph.model.Item;
+
+public interface ItemRepository extends JpaRepository<Item, Long> {
+
+    @EntityGraph(value = "Item.characteristics", type = EntityGraphType.FETCH)
+    Item findByName(String name);
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/exists/Car.java

@@ -0,0 +1,48 @@
+package com.baeldung.exists;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+/**
+ * @author paullatzelsperger
+ * @since 2019-03-20
+ */
+@Entity
+public class Car {
+
+    @Id
+    @GeneratedValue
+    private int id;
+    private Integer power;
+    private String model;
+
+    Car() {
+
+    }
+
+    public Car(int power, String model) {
+        this.power = power;
+        this.model = model;
+    }
+
+    public Integer getPower() {
+        return power;
+    }
+
+    public void setPower(Integer power) {
+        this.power = power;
+    }
+
+    public String getModel() {
+        return model;
+    }
+
+    public void setModel(String model) {
+        this.model = model;
+    }
+
+    public int getId() {
+        return id;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/exists/CarRepository.java

@@ -0,0 +1,24 @@
+package com.baeldung.exists;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+import org.springframework.stereotype.Repository;
+
+/**
+ * @author paullatzelsperger
+ * @since 2019-03-20
+ */
+@Repository
+public interface CarRepository extends JpaRepository<Car, Integer> {
+
+    boolean existsCarByPower(int power);
+
+    boolean existsCarByModel(String model);
+
+    @Query("select case when count(c)> 0 then true else false end from Car c where c.model = :model")
+    boolean existsCarExactCustomQuery(@Param("model") String model);
+
+    @Query("select case when count(c)> 0 then true else false end from Car c where lower(c.model) like lower(:model)")
+    boolean existsCarLikeCustomQuery(@Param("model") String model);
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/joins/model/Department.java

@@ -0,0 +1,45 @@
+package com.baeldung.joins.model;
+
+import java.util.List;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+
+@Entity
+public class Department {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    private String name;
+
+    @OneToMany(mappedBy = "department")
+    private List<Employee> employees;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public List<Employee> getEmployees() {
+        return employees;
+    }
+
+    public void setEmployees(List<Employee> employees) {
+        this.employees = employees;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/joins/model/Employee.java

@@ -0,0 +1,69 @@
+package com.baeldung.joins.model;
+
+import java.util.List;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "joins_employee")
+public class Employee {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private long id;
+
+    private String name;
+
+    private int age;
+
+    @ManyToOne
+    private Department department;
+
+    @OneToMany(mappedBy = "employee")
+    private List<Phone> phones;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(int age) {
+        this.age = age;
+    }
+
+    public Department getDepartment() {
+        return department;
+    }
+
+    public void setDepartment(Department department) {
+        this.department = department;
+    }
+
+    public List<Phone> getPhones() {
+        return phones;
+    }
+
+    public void setPhones(List<Phone> phones) {
+        this.phones = phones;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/java/com/baeldung/joins/model/Phone.java

@@ -0,0 +1,44 @@
+package com.baeldung.joins.model;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+
+@Entity
+public class Phone {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private long id;
+
+    private String number;
+
+    @ManyToOne
+    private Employee employee;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public String getNumber() {
+        return number;
+    }
+
+    public void setNumber(String number) {
+        this.number = number;
+    }
+
+    public Employee getEmployee() {
+        return employee;
+    }
+
+    public void setEmployee(Employee employee) {
+        this.employee = employee;
+    }
+}

persistence-modules/spring-data-jpa-query/src/main/resources/apple-fruit-data.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<fruit>
+    <id>1</id>
+    <name>apple</name>
+    <color>red</color>
+</fruit>

persistence-modules/spring-data-jpa-query/src/main/resources/application-joins.properties

@@ -0,0 +1 @@
+spring.datasource.data=classpath:db/import_joins.sql

persistence-modules/spring-data-jpa-query/src/main/resources/application.properties

@@ -0,0 +1 @@
+spring.jpa.show-sql=true

persistence-modules/spring-data-jpa-query/src/main/resources/db/import_joins.sql

@@ -0,0 +1,13 @@
+INSERT INTO department (id, name) VALUES (1, 'Infra');
+INSERT INTO department (id, name) VALUES (2, 'Accounting');
+INSERT INTO department (id, name) VALUES (3, 'Management');
+
+INSERT INTO joins_employee (id, name, age, department_id) VALUES (1, 'Baeldung', '35', 1);
+INSERT INTO joins_employee (id, name, age, department_id) VALUES (2, 'John', '35', 2);
+INSERT INTO joins_employee (id, name, age, department_id) VALUES (3, 'Jane', '35', 2);
+
+INSERT INTO phone (id, number, employee_id) VALUES (1, '111', 1);
+INSERT INTO phone (id, number, employee_id) VALUES (2, '222', 1);
+INSERT INTO phone (id, number, employee_id) VALUES (3, '333', 1);
+
+COMMIT;

persistence-modules/spring-data-jpa-query/src/main/resources/fruit-data.json

@@ -0,0 +1,14 @@
+[
+    {
+        "_class": "com.baeldung.entity.Fruit",
+        "name": "apple",
+        "color": "red",
+        "id": 1
+    },
+    {
+        "_class": "com.baeldung.entity.Fruit",
+        "name": "guava",
+        "color": "green",
+        "id": 2
+    }
+]

persistence-modules/spring-data-jpa-query/src/main/resources/guava-fruit-data.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<fruit>
+    <id>2</id>
+    <name>guava</name>
+    <color>green</color>
+</fruit>

persistence-modules/spring-data-jpa-query/src/main/resources/import_entities.sql

@@ -0,0 +1,3 @@
+insert into Article(id, publication_date, publication_time, creation_date_time) values(1, TO_DATE('01/01/2018', 'DD/MM/YYYY'), TO_DATE('15:00', 'HH24:MI'), TO_DATE('31/12/2017 07:30', 'DD/MM/YYYY HH24:MI'));
+insert into Article(id, publication_date, publication_time, creation_date_time) values(2, TO_DATE('01/01/2018', 'DD/MM/YYYY'), TO_DATE('15:30', 'HH24:MI'), TO_DATE('15/12/2017 08:00', 'DD/MM/YYYY HH24:MI'));
+insert into Article(id, publication_date, publication_time, creation_date_time) values(3, TO_DATE('15/12/2017', 'DD/MM/YYYY'), TO_DATE('16:00', 'HH24:MI'), TO_DATE('01/12/2017 13:45', 'DD/MM/YYYY HH24:MI'));