hazelcast-hibernate5.2-spring_boot

application.properties

spring.jpa.properties.hibernate.cache.region.factory_class=com.hazelcast.hibernate.HazelcastCacheRegionFactory
# Needed to use defined HazelcastInstance instead of creating a new one
spring.jpa.properties.hibernate.cache.hazelcast.instance_name=myHzInstance

HazelcastHibernateSpringApplication.java

package com.example.hazelcasthibernatespring;

import com.hazelcast.config.Config;
import com.hazelcast.core.Hazelcast;
import com.hazelcast.core.HazelcastInstance;
import lombok.Data;
import org.hibernate.annotations.Cache;
import org.hibernate.annotations.CacheConcurrencyStrategy;
import org.hibernate.annotations.CreationTimestamp;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.data.annotation.CreatedBy;
import org.springframework.data.jpa.repository.JpaRepository;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import java.time.LocalDateTime;
import java.util.UUID;
import java.util.stream.IntStream;

@SpringBootApplication
public class HazelcastHibernateSpringApplication {

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

	//Only needed to check size in CLI Bean, otherwise created automatically by
	// com.hazelcast.hibernate.instance.HazelcastInstanceLoader
	@Bean
	HazelcastInstance hazelcastInstance() {
		Config config = new Config().setInstanceName("myHzInstance");
		return Hazelcast.newHazelcastInstance(config);
	}

	@Bean
	CommandLineRunner clr(MyEntityRepo repo, HazelcastInstance hz) {
		return (String... args) -> {
			//save to DB
			IntStream.range(0, 100)
				.boxed()
				.map(i -> MyEntity.of("name-" + i))
				.forEach(repo::save);

			//get from Hazelcast to see Cache is working
			System.out.println(hz.getMap(MyEntity.class.getSimpleName()).size());
		};
	}

}


interface MyEntityRepo extends JpaRepository<MyEntity, UUID> {
}

@Entity
@Data
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE, region = "MyEntity")
class MyEntity {
	@Id
	@GeneratedValue
	private UUID id;

	private String name;

	@Column(updatable = false)
	@CreatedBy
	protected String createdBy;

	@Column(updatable = false)
	@CreationTimestamp
	protected LocalDateTime createdOn;

	public static MyEntity of(String name) {
		MyEntity entity = new MyEntity();
		entity.setName(name);
		return entity;
	}
}

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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.example</groupId>
	<artifactId>hazelcast-hibernate-spring</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>hazelcast-hibernate-spring</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.8.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
		<hazelcast.version>3.9</hazelcast.version>
		<hibernate.version>5.2.12.Final</hibernate.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>

		<dependency>
			<groupId>com.hazelcast</groupId>
			<artifactId>hazelcast-hibernate52</artifactId>
			<version>1.2.2</version>
		</dependency>
		<dependency>
			<groupId>com.hazelcast</groupId>
			<artifactId>hazelcast-spring</artifactId>
			<version>${hazelcast.version}</version>
		</dependency>
		<dependency>
			<groupId>com.h2database</groupId>
			<artifactId>h2</artifactId>
			<scope>runtime</scope>
		</dependency>
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<optional>true</optional>
		</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>

In fact, it works with v3.9 as well.

But now I'm getting:
com.hazelcast.core.DuplicateInstanceNameException: HazelcastInstance with name 'meetup_api_hazelcast_cluster' already exists!

I need to figure out either why that's happening, or how to turn off caching during tests.
Any ideas?

Hi eric ,

How did you fix this issue ?