Session 7

<?xml version="1.0" encoding="UTF-8"?>
<!-- admission-api/pom.xml : generated by Spring Initializr, Spring Boot 3.3.4, Java 17 -->
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>3.3.4</version>
    <relativePath/>
  </parent>

  <groupId>in.ignou</groupId>
  <artifactId>admission-api</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>admission-api</name>
  <description>MCSL-222 Student Admission API (Sessions 7 to 10)</description>

  <properties>
    <java.version>17</java.version>
  </properties>

  <dependencies>
    <!-- a. Spring MVC (embedded Tomcat, Jackson for JSON) -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!-- b. Hibernate and c. JPA: one starter brings hibernate-core and Spring Data JPA -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <!-- d. Thymeleaf view templates -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-thymeleaf</artifactId>
    </dependency>
    <!-- e. DevTools: automatic restart on save -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-devtools</artifactId>
      <scope>runtime</scope>
      <optional>true</optional>
    </dependency>
    <!-- f. Actuator: /actuator/health, /actuator/metrics ... -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <!-- g. MySQL driver -->
    <dependency>
      <groupId>com.mysql</groupId>
      <artifactId>mysql-connector-j</artifactId>
      <scope>runtime</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

// src/main/java/in/ignou/admission/AdmissionApiApplication.java
package in.ignou.admission;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * Entry point. @SpringBootApplication = @Configuration + @EnableAutoConfiguration
 * + @ComponentScan of the package in.ignou.admission and everything below it.
 */
@SpringBootApplication
public class AdmissionApiApplication {

    public static void main(String[] args) {
        SpringApplication.run(AdmissionApiApplication.class, args);
    }
}

// src/main/java/in/ignou/admission/entity/Student.java
package in.ignou.admission.entity;

import java.time.LocalDate;

import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;

/** Applicant. Maps to table `student` (Hibernate default: snake_case of the class name). */
@Entity
public class Student {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false, length = 80)
    private String name;

    @Column(nullable = false, unique = true, length = 120)
    private String email;

    @Column(length = 15)
    private String phone;

    @Column(length = 60)
    private String city;

    private LocalDate dateOfBirth;

    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 String getEmail() { return email; }
    public void setEmail(String email) { this.email = email; }
    public String getPhone() { return phone; }
    public void setPhone(String phone) { this.phone = phone; }
    public String getCity() { return city; }
    public void setCity(String city) { this.city = city; }
    public LocalDate getDateOfBirth() { return dateOfBirth; }
    public void setDateOfBirth(LocalDate dateOfBirth) { this.dateOfBirth = dateOfBirth; }
}

// src/main/java/in/ignou/admission/entity/Programme.java
package in.ignou.admission.entity;

import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;

/** A degree programme such as MCA or BCA. Table `programme`. */
@Entity
public class Programme {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false, unique = true, length = 10)
    private String code;

    @Column(nullable = false, length = 100)
    private String name;

    private int durationYears;

    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    public String getCode() { return code; }
    public void setCode(String code) { this.code = code; }
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public int getDurationYears() { return durationYears; }
    public void setDurationYears(int durationYears) { this.durationYears = durationYears; }
}

// src/main/java/in/ignou/admission/entity/Course.java
package in.ignou.admission.entity;

import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import jakarta.persistence.JoinColumn;
import jakarta.persistence.ManyToOne;

/** One course inside a programme. Table `course`, FK column `programme_id`. */
@Entity
public class Course {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false, unique = true, length = 10)
    private String code;

    @Column(nullable = false, length = 120)
    private String title;

    private int credits;

    @ManyToOne(optional = false)
    @JoinColumn(name = "programme_id")
    private Programme programme;

    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    public String getCode() { return code; }
    public void setCode(String code) { this.code = code; }
    public String getTitle() { return title; }
    public void setTitle(String title) { this.title = title; }
    public int getCredits() { return credits; }
    public void setCredits(int credits) { this.credits = credits; }
    public Programme getProgramme() { return programme; }
    public void setProgramme(Programme programme) { this.programme = programme; }
}

// src/main/java/in/ignou/admission/entity/AdmissionStatus.java
package in.ignou.admission.entity;

/** Life cycle of one application. Stored as a string column by @Enumerated(EnumType.STRING). */
public enum AdmissionStatus {
    APPLIED, VERIFIED, APPROVED, REJECTED
}

// src/main/java/in/ignou/admission/entity/Admission.java
package in.ignou.admission.entity;

import java.time.LocalDate;

import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.EnumType;
import jakarta.persistence.Enumerated;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import jakarta.persistence.JoinColumn;
import jakarta.persistence.ManyToOne;

/** A student applying to a programme. Table `admission`, FKs `student_id` and `programme_id`. */
@Entity
public class Admission {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @ManyToOne(optional = false)
    @JoinColumn(name = "student_id")
    private Student student;

    @ManyToOne(optional = false)
    @JoinColumn(name = "programme_id")
    private Programme programme;

    @Enumerated(EnumType.STRING)
    @Column(nullable = false, length = 10)
    private AdmissionStatus status = AdmissionStatus.APPLIED;

    private LocalDate appliedOn = LocalDate.now();

    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }
    public Student getStudent() { return student; }
    public void setStudent(Student student) { this.student = student; }
    public Programme getProgramme() { return programme; }
    public void setProgramme(Programme programme) { this.programme = programme; }
    public AdmissionStatus getStatus() { return status; }
    public void setStatus(AdmissionStatus status) { this.status = status; }
    public LocalDate getAppliedOn() { return appliedOn; }
    public void setAppliedOn(LocalDate appliedOn) { this.appliedOn = appliedOn; }
}

// src/main/java/in/ignou/admission/repository/StudentRepository.java
package in.ignou.admission.repository;

import java.util.List;
import java.util.Optional;

import org.springframework.data.jpa.repository.JpaRepository;

import in.ignou.admission.entity.Student;

/** No implementation needed: Spring Data generates it at start-up from the method names. */
public interface StudentRepository extends JpaRepository<Student, Long> {

    Optional<Student> findByEmail(String email);

    List<Student> findByCityIgnoreCase(String city);
}

// src/main/java/in/ignou/admission/repository/ProgrammeRepository.java
package in.ignou.admission.repository;

import java.util.Optional;

import org.springframework.data.jpa.repository.JpaRepository;

import in.ignou.admission.entity.Programme;

public interface ProgrammeRepository extends JpaRepository<Programme, Long> {

    Optional<Programme> findByCode(String code);
}

// src/main/java/in/ignou/admission/repository/CourseRepository.java
package in.ignou.admission.repository;

import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;

import in.ignou.admission.entity.Course;

public interface CourseRepository extends JpaRepository<Course, Long> {

    /** Walks the association: course.programme.code = ?1 */
    List<Course> findByProgrammeCode(String programmeCode);
}

// src/main/java/in/ignou/admission/repository/AdmissionRepository.java
package in.ignou.admission.repository;

import java.util.List;

import org.springframework.data.jpa.repository.JpaRepository;

import in.ignou.admission.entity.Admission;
import in.ignou.admission.entity.AdmissionStatus;

public interface AdmissionRepository extends JpaRepository<Admission, Long> {

    List<Admission> findByStatus(AdmissionStatus status);

    List<Admission> findByStudentId(Long studentId);
}

// src/main/java/in/ignou/admission/web/StudentRestController.java   (Session 7, Q32: read only)
package in.ignou.admission.web;

import java.util.List;

import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import in.ignou.admission.entity.Student;
import in.ignou.admission.repository.StudentRepository;

/**
 * @RestController = @Controller + @ResponseBody: every return value is written
 * to the HTTP body as JSON by Jackson instead of being resolved as a view name.
 */
@RestController
@RequestMapping("/api/students")
public class StudentRestController {

    private final StudentRepository students;

    // one constructor: Spring injects the repository, no @Autowired needed
    public StudentRestController(StudentRepository students) {
        this.students = students;
    }

    /** GET /api/students  or  GET /api/students?city=Jaipur */
    @GetMapping
    public List<Student> all(@RequestParam(required = false) String city) {
        return city == null ? students.findAll() : students.findByCityIgnoreCase(city);
    }

    /** GET /api/students/1 -> 200 with the student, or 404 with an empty body */
    @GetMapping("/{id}")
    public ResponseEntity<Student> one(@PathVariable Long id) {
        return students.findById(id)
                .map(ResponseEntity::ok)
                .orElse(ResponseEntity.notFound().build());
    }
}

-- src/main/resources/data.sql : seed rows, runs at every start-up.
-- Explicit ids + INSERT IGNORE so a second start-up does not duplicate rows (MySQL syntax).
INSERT IGNORE INTO programme (id, code, name, duration_years) VALUES
  (1, 'MCA', 'Master of Computer Applications', 2),
  (2, 'BCA', 'Bachelor of Computer Applications', 3);

INSERT IGNORE INTO course (id, code, title, credits, programme_id) VALUES
  (1, 'MCS-221', 'Data Warehousing and Data Mining', 4, 1),
  (2, 'MCSL-222', 'Web Technologies Lab', 2, 1),
  (3, 'BCS-011', 'Computer Basics and PC Software', 3, 2);

INSERT IGNORE INTO student (id, name, email, phone, city, date_of_birth) VALUES
  (1, 'Asha Verma', 'asha@example.com', '9876543210', 'Jaipur', '2002-03-14'),
  (2, 'Ravi Kumar', 'ravi@example.com', '9123456780', 'Patna', '2001-11-02');

INSERT IGNORE INTO admission (id, student_id, programme_id, status, applied_on) VALUES
  (1, 1, 1, 'APPLIED', '2026-07-01'),
  (2, 2, 1, 'APPROVED', '2026-06-20');