implementing hexagonal architecture for my own way

Author: amir_choubani

hexagonal-architecure/my-poc-hexagonal/pom.xml

@@ -27,6 +27,13 @@
 			<artifactId>h2</artifactId>
 			<scope>runtime</scope>
 		</dependency>
+
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<version>1.18.20</version>
+			<scope>provided</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-test</artifactId>

hexagonal-architecure/my-poc-hexagonal/src/main/java/com/example/hexagonal/hexademo/domain/Student.java

@@ -0,0 +1,72 @@
+package com.example.hexagonal.hexademo.domain;
+
+import java.util.UUID;
+
+public class Student {
+
+    private final UUID id;
+    private final String firstName;
+    private final String lastName;
+    private final Long age;
+
+    private Student(Builder builder) {
+        id = builder.id;
+        firstName = builder.firstName;
+        lastName = builder.lastName;
+        age = builder.age;
+    }
+
+    public UUID getId() {
+        return id;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public Long getAge() {
+        return age;
+    }
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static class Builder {
+        private UUID id;
+        private String firstName;
+        private String lastName;
+        private Long age;
+
+        Builder() {
+        }
+
+        public Builder id(UUID id) {
+            this.id = id;
+            return this;
+        }
+
+        public Builder firstName(String firstName) {
+            this.firstName = firstName;
+            return this;
+        }
+
+        public Builder lastName(String lastName) {
+            this.lastName = lastName;
+            return this;
+        }
+
+        public Builder age(Long age) {
+            this.age = age;
+            return this;
+        }
+
+        public Student build() {
+            return new Student(this);
+        }
+    }
+}

hexagonal-architecure/my-poc-hexagonal/src/main/java/com/example/hexagonal/hexademo/domain/usecases/StudentUseCase.java

@@ -0,0 +1,10 @@
+package com.example.hexagonal.hexademo.domain.usecases;
+
+import com.example.hexagonal.hexademo.domain.Student;
+
+import java.util.List;
+
+public interface StudentUseCase {
+
+    public List<Student> getAllStudents();
+}

hexagonal-architecure/my-poc-hexagonal/src/main/java/com/example/hexagonal/hexademo/infrastracture/primary/StudentController.java

@@ -0,0 +1,26 @@
+package com.example.hexagonal.hexademo.infrastracture.primary;
+
+import com.example.hexagonal.hexademo.domain.Student;
+import com.example.hexagonal.hexademo.domain.usecases.StudentUseCase;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/api/students")
+public class StudentController {
+
+    private final StudentUseCase studentUseCase;
+
+    public StudentController(StudentUseCase studentUseCase) {
+        this.studentUseCase = studentUseCase;
+    }
+
+    @RequestMapping("/get-all")
+    public ResponseEntity<List<StudentDTO>> getAll() {
+        List<Student> studentList = studentUseCase.getAllStudents();
+        return ResponseEntity.ok().body(StudentDTO.from(studentList));
+    }
+}

hexagonal-architecure/my-poc-hexagonal/src/main/java/com/example/hexagonal/hexademo/infrastracture/primary/StudentDTO.java

@@ -0,0 +1,57 @@
+package com.example.hexagonal.hexademo.infrastracture.primary;
+
+import com.example.hexagonal.hexademo.domain.Student;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.Setter;
+
+import java.util.List;
+import java.util.UUID;
+import java.util.stream.Collectors;
+
+@Builder
+@AllArgsConstructor
+@Getter
+@Setter
+public class StudentDTO {
+
+    private final UUID id;
+    private final String firstName;
+    private final String lastName;
+    private final Long age;
+
+    public static Student to(StudentDTO studentDTO) {
+        return Student
+                .builder()
+                .id(studentDTO.getId())
+                .firstName(studentDTO.getFirstName())
+                .lastName(studentDTO.getLastName())
+                .age(studentDTO.getAge())
+                .build();
+    }
+
+    public static StudentDTO from(Student student) {
+        return StudentDTO
+                .builder()
+                .id(student.getId())
+                .firstName(student.getFirstName())
+                .lastName(student.getLastName())
+                .age(student.getAge())
+                .build();
+    }
+
+    public static List<Student> to(List<StudentDTO> studentDTOList) {
+        return studentDTOList
+                .stream()
+                .map(StudentDTO::to)
+                .collect(Collectors.toList());
+    }
+
+    public static List<StudentDTO> from(List<Student> studentDTOList) {
+        return studentDTOList
+                .stream()
+                .map(StudentDTO::from)
+                .collect(Collectors.toList());
+    }
+}