Alright, I've looked around to find this answer for about an hour and I can't see it posted. So I bought the Spring Framework Master Class from in28minutes on Udemy. We have started implementing JPA. However, the Spring Boot versions are different( he is using 2.0.3, I am using 2.4.0). Now I know that's the issue. So the task is to simply connect to a h2 database, and interact with the data. Here is the current code setup I am using:
JpaDemoApplication.java
package com.in28minutes.database.databasedemo; import java.util.Date; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.CommandLineRunner; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import com.in28minutes.database.databasedemo.entity.Person; import com.in28minutes.database.databasedemo.jpa.PersonJpaRepository; @SpringBootApplication public class JpaDemoApplication implements CommandLineRunner { private Logger logger = LoggerFactory.getLogger(this.getClass()); @Autowired PersonJpaRepository repository; public static void main(String[] args) { SpringApplication.run(JpaDemoApplication.class, args); } @Override public void run(String... args) throws Exception { logger.info("User id 10001 -> {}", repository.findById(10001)); logger.info("Inserting -> {}", repository.insert(new Person("Tara", "Berlin", new Date()))); /* logger.info("Update 10003 -> {}", repository.update(new Person(10003, "Pieter", "Utrecht", new Date()))); //repository.deleteById(10002); logger.info("All users -> {}", repository.findAll()); */ } } Person.java
import java.util.Date; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.NamedQuery; @Entity @NamedQuery(name="find_all_persons", query="select p from Person p") public class Person { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private int id; private String name; private String location; private Date birthDate; public Person() {} public Person(int id, String name, String location, Date birthDate) { super(); this.id = id; this.name = name; this.location = location; this.birthDate = birthDate; } public Person(String name, String location, Date birthDate) { super(); this.name = name; this.location = location; this.birthDate = birthDate; } public int getId() { return id;} public void setId(int id) {this.id = id;} public String getName() {return name;} public void setName(String name) {this.name = name;} public String getLocation() {return location;} public void setLocation(String location) {this.location = location;} public Date getBirthDate() {return birthDate;} public void setBirthDate(Date birthDate) {this.birthDate = birthDate;} @Override public String toString() { return String.format("\nPerson [id=%s, name=%s, location=%s, birthDate=%s]", id, name, location, birthDate); } } PersonJpaRepository.java
package com.in28minutes.database.databasedemo.jpa; import java.util.List; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import javax.persistence.TypedQuery; import javax.transaction.Transactional; import org.springframework.stereotype.Repository; import com.in28minutes.database.databasedemo.entity.Person; @Repository @Transactional public class PersonJpaRepository { // connect to the database @PersistenceContext EntityManager entityManager; public List<Person> findAll() { TypedQuery<Person> namedQuery = entityManager.createNamedQuery("find_all_persons", Person.class); return namedQuery.getResultList(); } public Person findById(int id) { return entityManager.find(Person.class, id);// JPA } public Person update(Person person) { return entityManager.merge(person); } public Person insert(Person person) { return entityManager.merge(person); } public void deleteById(int id) { Person person = findById(id); entityManager.remove(person); } } application.properties
spring.h2.console.enabled=true spring.jpa.show-sql=true #logging.level.root=debug #spring.jpa.hibernate.use-new-id-generator-mappings=false spring.jpa.hibernate.ddl-auto=none spring.datasource.url=jdbc:h2:mem:testdb spring.data.jpa.repositories.bootstrap-mode=default data.sql
INSERT INTO PERSON (ID, NAME, LOCATION, BIRTH_DATE) VALUES(10001, 'Ranga', 'Hyderabad', sysdate()); INSERT INTO PERSON (ID, NAME, LOCATION, BIRTH_DATE) VALUES(10002, 'James', 'New York', sysdate()); INSERT INTO PERSON (ID, NAME, LOCATION, BIRTH_DATE) VALUES(10003, 'Pieter', 'Amsterdam', sysdate()); schema.sql
create table person ( id integer not null, name varchar(255) not null, location varchar(255), birth_date timestamp, primary key(id) ); pom.xml
<?xml version="1.0" encoding="UTF-8"?> <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>2.4.0</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.in28minutes.database</groupId> <artifactId>database-demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>database-demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>15</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>com.h2database</groupId> <artifactId>h2</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> I know this is a lot, but I am very new to Spring, and I HAVE to have this down by January, due to me starting a new job. The specific error is that the table is created, the first select by id works, but the insert passes a null value:
Hibernate: insert into person (id, birth_date, location, name) values (null, ?, ?, ?) 2020-12-03 10:59:16.724 WARN 14464 --- [ main] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 23502, SQLState: 23502 2020-12-03 10:59:16.724 ERROR 14464 --- [ main] o.h.engine.jdbc.spi.SqlExceptionHelper : NULL not allowed for column "ID"; SQL statement: insert into person (id, birth_date, location, name) values (null, ?, ?, ?) [23502-200] I have tried 5 different suggestions, but none have worked. What am I doing wrong? Pointing to something that can explain how to do it works as well, I'm always looking for more current learning resources.
