Spring认证指南：如何在 Neo4j 的 NoSQL 数据存储中持久化对象和关系

$酿造安装neo4j

$ neo4j 开始

启动 Neo4j。
启动 neo4j (pid 96416)。默认情况下，它位于 http://localhost:7474/
在服务器准备好之前可能会有短暂的延迟。
有关当前状态，请参见 /usr/local/Cellar/neo4j/3.0.6/libexec/logs/neo4j.log。

curl -v -u neo4j:neo4j POST localhost:7474/user/neo4j/password -H "Content-type:application/json" -d "{\"password\":\"secret\"}"

package com.example.accessingdataneo4j;

import java.util.Collections;
import java.util.HashSet;
import java.util.Optional;
import java.util.Set;
import java.util.stream.Collectors;

import org.springframework.data.neo4j.core.schema.Id;
import org.springframework.data.neo4j.core.schema.Node;
import org.springframework.data.neo4j.core.schema.Property;
import org.springframework.data.neo4j.core.schema.Relationship;
import org.springframework.data.neo4j.core.schema.GeneratedValue;

@Node
public class Person {

  @Id @GeneratedValue private Long id;

  private String name;

  private Person() {
    // Empty constructor required as of Neo4j API 2.0.5
  };

  public Person(String name) {
    this.name = name;
  }

  
  @Relationship(type = "TEAMMATE")
  public Set<Person> teammates;

  public void worksWith(Person person) {
    if (teammates == null) {
      teammates = new HashSet<>();
    }
    teammates.add(person);
  }

  public String toString() {

    return this.name + "'s teammates => "
      + Optional.ofNullable(this.teammates).orElse(
          Collections.emptySet()).stream()
            .map(Person::getName)
            .collect(Collectors.toList());
  }

  public String getName() {
    return name;
  }

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

package com.example.accessingdataneo4j;

import java.util.List;
import org.springframework.data.neo4j.repository.Neo4jRepository;

public interface PersonRepository extends Neo4jRepository<Person, Long> {

  Person findByName(String name);
  List<Person> findByTeammatesName(String name);
}

spring.neo4j.uri=bolt://localhost:7687
spring.data.neo4j.username=neo4j
spring.data.neo4j.password=secret

package com.example.accessingdataneo4j;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class AccessingDataNeo4jApplication {

  public static void main(String[] args) {
    SpringApplication.run(AccessingDataNeo4jApplication.class, args);
  }

}

package com.example.accessingdataneo4j;

import java.util.Arrays;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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.neo4j.repository.config.EnableNeo4jRepositories;

@SpringBootApplication
@EnableNeo4jRepositories
public class AccessingDataNeo4jApplication {

  private final static Logger log = LoggerFactory.getLogger(AccessingDataNeo4jApplication.class);

  public static void main(String[] args) throws Exception {
    SpringApplication.run(AccessingDataNeo4jApplication.class, args);
    System.exit(0);
  }

  @Bean
  CommandLineRunner demo(PersonRepository personRepository) {
    return args -> {

      personRepository.deleteAll();

      Person greg = new Person("Greg");
      Person roy = new Person("Roy");
      Person craig = new Person("Craig");

      List<Person> team = Arrays.asList(greg, roy, craig);

      log.info("Before linking up with Neo4j...");

      team.stream().forEach(person -> log.info("\t" + person.toString()));

      personRepository.save(greg);
      personRepository.save(roy);
      personRepository.save(craig);

      greg = personRepository.findByName(greg.getName());
      greg.worksWith(roy);
      greg.worksWith(craig);
      personRepository.save(greg);

      roy = personRepository.findByName(roy.getName());
      roy.worksWith(craig);
      // We already know that roy works with greg
      personRepository.save(roy);

      // We already know craig works with roy and greg

      log.info("Lookup each person by name...");
      team.stream().forEach(person -> log.info(
          "\t" + personRepository.findByName(person.getName()).toString()));

      List<Person> teammates = personRepository.findByTeammatesName(greg.getName());
      log.info("The following have Greg as a teammate...");
      teammates.stream().forEach(person -> log.info("\t" + person.getName()));
    };
  }

}

java -jar build/libs/gs-accessing-data-neo4j-0.1.0.jar

java -jar 目标/gs-accessing-data-neo4j-0.1.0.jar

在与 Neo4j 连接之前...
  格雷格的队友 => []
  罗伊的队友 => []
  克雷格的队友 => []

按姓名查找每个人...
  格雷格的队友 => [罗伊，克雷格]
  罗伊的队友 => [格雷格，克雷格]
  克雷格的队友 => [罗伊，格雷格]