muasif80@gmail.com (#13262)

* BAEL-6063

* Updated the unit test class name

* Fixed the test

* Made updates to method names for tests and some refactor of code

* Updated the formatting using Baeldung formatter for Java

* Removed the space around = and made line continuations 2 spaces

persistence-modules/spring-data-jpa-repo-2/src/main/java/com/baeldung/spring/data/persistence/search/Student.java

@@ -0,0 +1,75 @@
+package com.baeldung.spring.data.persistence.search;
+
+import java.util.Objects;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+
+@Entity
+public class Student {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    private String name;
+    private int score;
+
+    public Student() {
+    }
+
+    public Student(String name, int score) {
+
+        this.name = name;
+        this.score = score;
+    }
+
+    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 getScore() {
+        return score;
+    }
+
+    public void setScore(int score) {
+        this.score = score;
+    }
+
+    @Override
+    public String toString() {
+        return "Student [id=" + id + ", name=" + name + ", score=" + score + "]";
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(id, name, score);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        Student other = (Student) obj;
+        return id == other.id && Objects.equals(name, other.name) && score == other.score;
+    }
+
+}

persistence-modules/spring-data-jpa-repo-2/src/main/java/com/baeldung/spring/data/persistence/search/StudentApplication.java

@@ -0,0 +1,16 @@
+package com.baeldung.spring.data.persistence.search;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class StudentApplication {
+
+    private static final Logger log = LoggerFactory.getLogger(StudentApplication.class);
+
+    public static void main(String[] args) {
+        SpringApplication.run(StudentApplication.class, args);
+    }
+}

persistence-modules/spring-data-jpa-repo-2/src/main/java/com/baeldung/spring/data/persistence/search/StudentRepository.java

@@ -0,0 +1,31 @@
+package com.baeldung.spring.data.persistence.search;
+
+import java.util.List;
+
+import org.springframework.data.domain.Sort;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface StudentRepository extends JpaRepository<Student, Long> {
+
+    Student findFirstByOrderByScoreDesc();
+
+    Student findFirstBy(Sort sort);
+
+    Student findFirstByNameLike(String name, Sort sort);
+
+    List<Student> findFirst3ByOrderByScoreDesc();
+
+    List<Student> findFirst2ByScoreBetween(int startScore, int endScore, Sort sort);
+
+    Student findTopByOrderByScoreDesc();
+
+    Student findTopBy(Sort sort);
+
+    Student findTopByNameLike(String name, Sort sort);
+
+    List<Student> findTop3ByOrderByScoreDesc();
+
+    List<Student> findTop2ByScoreBetween(int startScore, int endScore, Sort sort);
+}

persistence-modules/spring-data-jpa-repo-2/src/main/resources/application.properties

@@ -3,3 +3,4 @@ spring.datasource.username=sa
 spring.datasource.password=sa
 
 spring.jpa.properties.hibernate.globally_quoted_identifiers=true
+logging.level.com.baeldung.spring.data.persistence.search=debug

persistence-modules/spring-data-jpa-repo-2/src/test/java/com/baeldung/spring/data/persistence/search/StudentApplicationUnitTest.java

@@ -0,0 +1,100 @@
+package com.baeldung.spring.data.persistence.search;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Random;
+import java.util.stream.Collectors;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.data.domain.Sort;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class StudentApplicationUnitTest {
+
+    @Autowired
+    private StudentRepository studentRepo;
+    private List<Student> students;
+
+    @Before
+    public void fillData() {
+        students = new ArrayList<>();
+        int count = 10;
+        Random r = new Random();
+        List<Integer> scores = r.ints(0, 101)
+          .distinct()
+          .limit(count)
+          .boxed()
+          .collect(Collectors.toList());
+
+        for (int i = 0; i < count; i++) {
+            Integer score = scores.get(i);
+            Student s = new Student("Student-" + i, score);
+            students.add(s);
+        }
+
+        studentRepo.saveAll(students);
+        Comparator<Student> c = Comparator.comparing(a -> a.getScore());
+        c = c.reversed();
+        students.sort(c);
+    }
+
+    @After
+    public void clearData() {
+        studentRepo.deleteAll();
+    }
+
+    @Test
+    public void givenStudentScores_whenMoreThanOne_thenFindFirst() {
+
+        Student student = studentRepo.findFirstByOrderByScoreDesc();
+        Student s = students.get(0);
+        assertEquals(student, s);
+    }
+
+    @Test
+    public void givenStudentScores_whenMoreThan3_thenFindFirstThree() {
+
+        List<Student> firstThree = studentRepo.findFirst3ByOrderByScoreDesc();
+        List<Student> sList = students.subList(0, 3);
+        assertArrayEquals(firstThree.toArray(), sList.toArray());
+    }
+
+    @Test
+    public void givenStudentScores_whenNameMatches_thenFindFirstStudent() {
+
+        String matchString = "3";
+        Student student = studentRepo.findFirstByNameLike("%" + matchString + "%", Sort.by("score")
+          .descending());
+        Student s = students.stream()
+          .filter(a -> a.getName()
+          .contains(matchString))
+          .findFirst()
+          .orElse(null);
+        assertEquals(student, s);
+    }
+
+    @Test
+    public void givenStudentScores_whenBetweenRange_thenFindFirstTwoStudents() {
+
+        List<Student> topTwoBetweenRange = studentRepo.findFirst2ByScoreBetween(50, 60, Sort.by("score")
+          .descending());
+        List<Student> _students = students.stream()
+          .filter(a -> a.getScore() >= 50 && a.getScore() <= 60)
+          .limit(2)
+          .collect(Collectors.toList());
+        assertArrayEquals(_students.toArray(), topTwoBetweenRange.toArray());
+    }
+}