Spring Boot RESTful API - JPA Hibernate MySQL Example

by S.M.Lee(phantasmicmeans)

RESTful API using Spring Boot, Swagger2, JPA hibernate and Mysql, One to Many, Many to One bidirectional mapping

 

Relation

Bidirectional Mapping

• Project - Problem (One-To-Many)

• Problem - Project (Many-To-One)

• Problem - SubProblem (One-To-Many)

• SubProblem - Problem (Many-To-One)

 

Before we go, Check the domain class

1. Problem.java(part of)

@OneToMany(mappedBy = "project", cascade = CascadeType.REMOVE, fetch = FetchType.LAZY, orphanRemoval = true)
private Set <Problem> problems = new HashSet<>();
/* Project <-> Problem One to Many bidirectional */

2. Problem.java(part of)

@ManyToOne(cascade = CascadeType.REMOVE)
@JoinColumn(name = "code", referencedColumnName = "code", nullable = false)
private Project project; 
/* Problem <-> Project  Many to One bidirectional */

@OneToMany(mappedBy = "problem", cascade = CascadeType.ALL, fetch = FetchType.LAZY, orphanRemoval = true)
private Set<subProblem> subProblems = new HashSet<>();
//Problem <-> SubProblem  One to Many bidirectional

3. SubProblem.java(part of)

@ManyToOne(cascade = CascadeType.REMOVE)
@JoinColumn(name = "pro_idx", referencedColumnName = "idx", nullable = false)
private Problem problem; 
/* Problem <-> Project Many to One bidirectional */

 

RESTful API Server

  1. API Description for Project

METHOD	PATH	DESCRIPTION
GET	/api/project/{code}	get Project-Problem-SubProblem with code
POST	/api/project	save Project (code will generate by constructor)
DELETE	/api/project/{code}	delete Project with code
PUT	/api/project/{code}	update Project with code

  2. API Description for Problem & SubProblem

METHOD	PATH	DESCRIPTION
GET	/api/problem/{code}	get all Problem-Subproblem with code
POST	/api/problem/{code}	save Problem with code
DELETE	/api/problem/{code}/all	delete all Problem-Subproblem with code
POST	/api/subproblem	save Subproblem

 

Curl

  1. Curl for Project

1. Get a Project with code

curl -X GET http://localhost:8080/problem/0gn547 

2. Save a Project with code

curl -d '{"title":"first project"}' -H "Content-Type: application/json" -X POST http://localhost:8080/project

3. Delete a Project with code

curl -X DELETE http://localhost:8001/project/0gn547

4. Update a Project with code

curl -X PUT -H "Content-Type: application/json; charset=utf-8" -d '{"title":"first-project-renewal"}' http://localhost:8080/project/hx6029

 

2. Curl for Problem & SubProblem  

1. Get a Problem with code

curl -X GET http://localhost:8001/problem/0gn547 

2. Save a Problem with code

curl -d '{"title":"first problem"}' -H "Content-Type: application/json" -X POST http://localhost:8080/problem/hx6029

3. Delete a Problem-SubProblem with code

curl -X DELETE http://localhost:8001/problem/hx6029/all 

4. Save a SubProblem

curl -d '{"content":"first-subproblem","pro_idx":1}' -H "Content-Type: application/json" -X POST http://localhost:8080/subproblem

 

Running the project with MySQL

append this at the end of application.yml  

spring:
    application:
      name: project-api
       
## Hibernate Properties
# The SQL dialect makes Hibernate generate better SQL for the chosen database
    jpa: 
      properties:
        hibernate:
          dialect: org.hibernate.dialect.MySQL5InnoDBDialect
      hibernate:
        ddl-auto: update
        # Hibernate ddl auto (create, create-drop, validate, update)
      
    datasource:
      url: jdbc:mysql://{YOUR_MSQL_SERVER}:3306/{DATABASE NAME}?useSSL=false
      username: {YOUR_MYSQL_ID}
      password: {YOUR_MYSQL{PASSWORD}
      driver-class-name: com.mysql.jdbc.Driver
      hikari:
        maximum-pool-size: 2

 

Swagger

You can use the Swagger API Documentation at http://{Your_Server}:{Port}/swagger-ui.html