Overview

NucleoDB Spring Repository Library makes it easier to use NucleoDB.

Installation

Dependencies

• Kafka Cluster
  • /docker/kafka/docker-compose.yml

Import library

repositories {
    mavenCentral()
    maven { url "https://nexus.synload.com/repository/maven-repo-releases/" }
}
dependencies {
    implementation 'com.nucleodb:spring:3.3.13'
}

Initializing DB

@SpringBootApplication
@EnableNDBRepositories(
        dbType = NucleoDB.DBType.NO_LOCAL, // does not create a disk of current up-to-date version of DB
        // Feature: Read To Time, will read only changes equal to or before the date set.
        //readToTime = "2023-12-17T00:42:32.906539Z",
        scanPackages = {
                "com.package.string" // scan for @Table classes
        },
        basePackages = "com.package.string.repos"
)
class Application{
  public static void main(String[] args) {
    SpringApplication.run(Application.class);
  }
}

DataEntry model files

import java.io.Serializable;

@Table(tableName = "author", dataEntryClass = AuthorDE.class)
public class Author implements Serializable {
  @Index
  String name;
  public Author(String name) {
    this.name = name;
  }
  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }
}

public class AuthorDE extends DataEntry<Author>{
  
}

Repository for DataEntry

@Repository
public interface AuthorDataRepository extends NDBDataRepository<AuthorDE, String>{
  Set<AuthorDE> findByNameAndKey(String name, String key);
  Author findByName(String name);
  void deleteByName(String name);
}

Connection model files

@Conn("CONNECTION_BETWEEN_DE")
public class ConnectionBetweenDataEntryClasses extends Connection<ConnectingToDataEntryDE, ConnectingFromDataEntryDE>{
  public ConnectionBetweenDataEntryClasses() {
  }

  public ConnectionBetweenDataEntryClasses(ConnectingFromDataEntryDE from, ConnectingToDataEntryDE to) {
    super(from, to);
  }

  public ConnectionBetweenDataEntryClasses(ConnectingFromDataEntryDE from, ConnectingToDataEntryDE to, Map<String, String> metadata) {
    super(from, to, metadata);
  }
}

Repository for Connections

@Repository
public interface ConnectionRepository extends NDBConnRepository<ConnectionBetweenDataEntryClasses, String, ConnectingFromDataEntryDE, ConnectingFromDataEntryDE>{
  
}