Spring Rest API + CRUD Example + Spring Boot + Oracle Database + Spring JPA

Hello everyone,

Greetings today!

Today we will use spring boot to create a REST API for CRUD operations.

The APIs that we will be developing at the end are listed below.

Get All Books [HTTP Method -GET & Request URL - localhost:8080/book]

GET Book By Id [HTTP Method -GET & Request URL - localhost:8080/book/{bookId}]

Add Book [HTTP Method -POST & Request URL - localhost:8080/book]

Request Payload

{ "book_title":"Spring REST API ", "book_price":"677", "book_author":"TEST" }

Delete Book [HTTP Method- Delete & Request URL - localhost:8080/book/{bookId}]

Update Book [Http Method -PUT & Request URL - localhost:8080/book/{bookId}]

{ "book_title":"Spring REST API ", "book_price":"750", "book_author":"TEST" }

So let's get started.

Go to spring initialize and create a basic project structure with the dependencies listed below. And then open the project in the IDE.

Now that we're using the Oracle database, let's add an oracle dependency to the pom.xml file.


<dependency>
  <groupId>oracle</groupId>
  <artifactId>ojdbc6</artifactId>
  <version>11.2.0.3</version>
</dependency>

Below is the project structure we will be developing.

Now, in application.properties, add database-related configuration.

spring.datasource.url=jdbc:oracle:thin:@localhost:1521:orcl
spring.datasource.username=username
spring.datasource.password=password
spring.datasource.driver-class-name=oracle.jdbc.driver.OracleDriver
spring.jpa.hibernate.ddl-auto=update

Let's create tables and sequences to store books.

CREATE TABLE "SYSTEM"."BOOKS" 
 (	
  "BOOK_ID" NUMBER(19,0), 
  "BOOK_AUTHOR" VARCHAR2(255 CHAR), 
  "BOOK_PRICE" NUMBER(19,2), 
  "BOOK_TITLE" VARCHAR2(255 CHAR)
);

create sequence book_id_sequence;

Let's now create a model class that will be mapped to the Books tables. We'll also include the JSON property we want to return as a response.

package com.spring.rest.demo.model;

import com.fasterxml.jackson.annotation.JsonProperty;
import lombok.AllArgsConstructor;
import lombok.NoArgsConstructor;
import lombok.ToString;

import javax.persistence.*;
import java.math.BigDecimal;

@Table(name = "Books")
@Entity
@AllArgsConstructor
@ToString
@NoArgsConstructor
public class Book {

    @JsonProperty(value = "book_id",required = false)
    @Column(name = "BOOK_ID")
    @GeneratedValue(strategy = GenerationType.SEQUENCE,generator = "book_id_seq")
    @SequenceGenerator(name = "book_id_seq",sequenceName = "book_id_sequence")
    @Id
    private Long bookId;

    @JsonProperty("book_title")
    @Column(name = "BOOK_TITLE")
    private String bookTitle;

    @JsonProperty("book_price")
    @Column(name = "BOOK_PRICE")
    private BigDecimal bookPrice;

    @JsonProperty("book_author")
    @Column(name = "BOOK_AUTHOR")
    private String bookAuthor;

}

We will now add repository layer code to the JPA repository, which will provide basic methods such as save, delete, findById, and so on.

package com.spring.rest.demo.repository;

import com.spring.rest.demo.model.Book;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface BookRepository extends JpaRepository<Book,Long> {
}

As previously stated, we will create a REST endpoint in our controller by using the POST, GET, DELETE, and PUT HTTP methods for operations such as create, read, delete, and update.

package com.spring.rest.demo.controller;

import com.spring.rest.demo.model.Book;
import com.spring.rest.demo.repository.BookRepository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

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

@RestController
@RequestMapping("/book")
public class BookController {

    private static Logger logger= LoggerFactory.getLogger(BookController.class);

    @Autowired
    private BookRepository bookRepository;

    @GetMapping(value = "/")
    public ResponseEntity<List<Book>> getAllBooks(){
        List<Book> books=bookRepository.findAll();
        return new ResponseEntity<List<Book>>(books, HttpStatus.OK);
    }

    @GetMapping(value = "/{bookId}")
    public ResponseEntity<Book> getBook(Long bookId){
        Optional<Book> book=bookRepository.findById(bookId);
        if(!book.isPresent()){
            return new ResponseEntity<Book>(HttpStatus.NOT_FOUND);
        }else {
            return new ResponseEntity<Book>(book.get(),HttpStatus.OK);
        }
    }

    @DeleteMapping(value = "/{bookId}")
    public ResponseEntity<String> deleteBook(@PathVariable("bookId") Long bookId){
      Optional<Book> book=bookRepository.findById(bookId);
      if(!book.isPresent()){
        return new ResponseEntity<String>("Book not found",HttpStatus.NOT_FOUND);
      }else {
        return new ResponseEntity<String>("Book deleted",HttpStatus.OK);
      }
    }

    @PostMapping(value = "/")
    public ResponseEntity<Book> addBook(@RequestBody Book book){
        book=bookRepository.saveAndFlush(book);
        return new ResponseEntity<Book>(book,HttpStatus.CREATED);
    }
    
    @PutMapping(value = "/")
    public ResponseEntity<Book> updateBook(@RequestBody Book book){
        book=bookRepository.saveAndFlush(book);
        return new ResponseEntity<Book>(book,HttpStatus.ACCEPTED);
    }
}

So, congratulations, we have finished this example.

Visit Spring Boot REST API File Upload With JSON Data In Single API Call to learn how we can upload files along with JSON data.

Refer to Spring Boot REST API Validation Using Annotations to learn how to validate REST API Requests.

Thanks

Enjoy your learning!

Another post you can refer to is

Spring Boot JDBC Template CRUD Operation

Spring REST API Authentication Using JWT + Spring Security JWT Authentication With Spring Boot

Named Query In Hibernate & JPA + @NamedNativeQuery + @NamedQuery

Spring Boot REST API Export To Excel Using Apache POI

Spring Batch Example Database To CSV Export

Set-Up Liquibase With Spring Boot