Neo4j访问的两种方式

嵌入式数据库
服务器模式(通过REST的访问)
它是由应用程序的性质（neo4j是独立服务器 还是和程序在一起),性能，监控和数据安全性来决定架构选择。

An embedded database（嵌入式数据库）

嵌入式Neo4j数据库是性能的最佳选择。 通过指定数据存储的路径以编程方式访问嵌入式数据库。
我们选择嵌入式数据库出于以下原因：

  • 使用Java作为我们项目的编程语言时
  • 应用程序是独立的
  • 程序追求很高的性能

    Neo4j Server（服务器模式）

    Neo4j Server是相互操作性，安全性和监控的最佳选择。 实际上，REST接口允许所有现代平台和编程语言与它进行互操作。 此外，作为独立应用程序，它比嵌入式配置更安全（客户端中的潜在故障不会影响服务器），并且更易于监控。 如果我们选择使用这种模式，我们的应用程序将充当Neo4j服务器的客户端。要连接到Neo4j服务器，可以使用任何编程语言的REST 访问数据库。

    Java客户端操作Neo4j

    嵌入式模式

    org.neo4j neo4j 3.5.5


package com.lagou; import org.neo4j.graphdb.*; import org.neo4j.graphdb.factory.GraphDatabaseFactory; import java.io.File; import java.util.HashMap; import java.util.Map; public class EmbeddedNeo4jAdd { private static final File databaseDirectory = new File( “target/graph.db” ); public static void main(String[] args) { GraphDatabaseService graphDb = new GraphDatabaseFactory().newEmbeddedDatabase(databaseDirectory); System.out.println(“Database Load!”);

Transaction tx = graphDb.beginTx();

Node n1 = graphDb.createNode();

n1.setProperty(“name”, “张三”);

n1.setProperty(“character”, “A”);

n1.setProperty(“gender”,1);

n1.setProperty(“money”, 1101);

n1.addLabel(new Label() {

@Override

public String name() {

return “Person”;

}

});

String cql = “CREATE (p:Person{name:’李

四’,character:’B’,gender:1,money:21000})”;

graphDb.execute(cql);

tx.success();

tx.close();

System.out.println(“Database Shutdown!”);

graphDb.shutdown();

}

}

package com.lagou;

import org.neo4j.graphdb.*;

import org.neo4j.graphdb.factory.GraphDatabaseFactory;

import java.io.File;

import java.util.HashMap;

import java.util.Map;

public class EmbeddedNeo4jQueryAll { private static final File databaseDirectory = new File( “target/graph.db” );

public static void main(String[] args) {

GraphDatabaseService graphDb = new

GraphDatabaseFactory().newEmbeddedDatabase(databaseDirectory);

System.out.println(“Database Load!”);

String cql = “MATCH (a:Person) where a.money < $money return a”;

Map paramerters = new HashMap();

paramerters.put(“money”, 25000);

Transaction tx = graphDb.beginTx();

Result result = graphDb.execute(cql,paramerters);

while (result.hasNext()) {

Map row = result.next();

for (String key : result.columns()) {

Node nd = (Node) row.get(key);

System.out.printf(“%s = %s:%s%n”, key,

nd.getProperty(“name”),nd.getProperty(“money”));

}

}

tx.success();

tx.close();

System.out.println(“Database Shutdown!”);

graphDb.shutdown();

}

}

服务器模式

org.neo4j neo4j-ogm-bolt-driver 3.2.10


package com.lagou;

import org.neo4j.driver.*;

import static org.neo4j.driver.Values.parameters;

public class Neo4jServerMain {

public static void main(String[] args) {

Driver driver = GraphDatabase.driver( “bolt://127.0.0.1:7687”,

AuthTokens.basic( “neo4j”, “123456” ) );

Session session = driver.session();

String cql = “MATCH (a:Person) WHERE a.money > $money “ +

“RETURN a.name AS name, a.money AS money order by a.money “;

Result result = session.run( cql,parameters( “money”, 1000 ) );

while ( result.hasNext() )

{

Record record = result.next();

System.out.println( record.get( “name” ).asString() + “ “ +

record.get( “money” ).asDouble() );

}

session.close();

driver.close();

}

}


package com.lagou;

import org.neo4j.driver.*;

import static org.neo4j.driver.Values.parameters;

public class Neo4jServerMain2 {

public static void main(String[] args) {

Driver driver = GraphDatabase.driver( “bolt://127.0.0.1:7687”,

AuthTokens.basic( “neo4j”, “123456” ) );

Session session = driver.session();

String cql = “MATCH p=shortestPath((person:Person {name:$startName})-

[*]-(person2:Person {name:$endName} )) RETURN p”;

Result result = session.run( cql,parameters(“startName”,”王启

年”,”endName”,”九品射手燕小乙”) );

while ( result.hasNext() )

{

Record record = result.next();

System.out.println(record);

}

session.close();

driver.close();

}

}

SpringBoot 整合Neo4j

pom.xml配置

  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <project xmlns="http://maven.apache.org/POM/4.0.0"
  3.          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  4.          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  5.     <modelVersion>4.0.0</modelVersion>
  7.     <groupId>com.lagou</groupId>
  8.     <artifactId>springboot_neo4j_demo</artifactId>
  9.     <version>1.0-SNAPSHOT</version>
  10.     <parent>
  11.         <groupId>org.springframework.boot</groupId>
  12.         <artifactId>spring-boot-starter-parent</artifactId>
  13.         <version>2.0.5.RELEASE</version>
  14.     </parent>
  16.     <dependencies>
  17.         <dependency>
  18.             <groupId>org.springframework.boot</groupId>
  19.             <artifactId>spring-boot-starter-data-neo4j</artifactId>
  20.         </dependency>
  21.         <dependency>
  22.             <groupId>org.neo4j</groupId>
  23.             <artifactId>neo4j-ogm-bolt-driver</artifactId>
  24.         </dependency>
  25.     </dependencies>
  27. </project>

创建实体类

  1. package com.lagou.bean;
  3. import org.neo4j.ogm.annotation.*;
  5. import java.util.Set;
  7. @NodeEntity
  8. public class Person {
  9.     @Id
  10.     @GeneratedValue
  11.     private Long  id;
  12.     @Property("cid")
  13.     private int   pid;
  14.     private String name;
  15.     private String  character;
  16.     private double  money;
  17.     private int   age;
  18.     private String description;
  19.     @Relationship(type = "Friends",direction = Relationship.OUTGOING)
  20.     private Set<Person>  friendsPerson;
  23.     public Set<Person> getFriendsPerson() {
  24.         return friendsPerson;
  25.     }
  27.     public void setFriendsPerson(Set<Person> friendsPerson) {
  28.         this.friendsPerson = friendsPerson;
  29.     }
  31.     public Person(Long id, int pid, String name, String character, double money, int age, String description) {
  32.         this.id = id;
  33.         this.pid = pid;
  34.         this.name = name;
  35.         this.character = character;
  36.         this.money = money;
  37.         this.age = age;
  38.         this.description = description;
  39.     }
  41.     public Person() {
  42.     }
  44.     public Long getId() {
  45.         return id;
  46.     }
  48.     @Override
  49.     public String toString() {
  50.         return "Person{" +
  51.                 "id=" + id +
  52.                 ", pid=" + pid +
  53.                 ", name='" + name + '\'' +
  54.                 ", character='" + character + '\'' +
  55.                 ", money=" + money +
  56.                 ", age=" + age +
  57.                 ", description='" + description + '\'' +
  58.                 ", friendsPerson=" + friendsPerson +
  59.                 '}';
  60.     }
  62.     public void setId(Long id) {
  63.         this.id = id;
  64.     }
  66.     public int getPid() {
  67.         return pid;
  68.     }
  70.     public void setPid(int pid) {
  71.         this.pid = pid;
  72.     }
  74.     public String getName() {
  75.         return name;
  76.     }
  78.     public void setName(String name) {
  79.         this.name = name;
  80.     }
  82.     public String getCharacter() {
  83.         return character;
  84.     }
  86.     public void setCharacter(String character) {
  87.         this.character = character;
  88.     }
  90.     public double getMoney() {
  91.         return money;
  92.     }
  94.     public void setMoney(double money) {
  95.         this.money = money;
  96.     }
  98.     public int getAge() {
  99.         return age;
  100.     }
  102.     public void setAge(int age) {
  103.         this.age = age;
  104.     }
  106.     public String getDescription() {
  107.         return description;
  108.     }
  110.     public void setDescription(String description) {
  111.         this.description = description;
  112.     }
  113. }

数据持久化类

  1. package com.lagou.repository;
  3. import com.lagou.bean.Person;
  4. import org.springframework.data.neo4j.annotation.Query;
  5. import org.springframework.data.neo4j.repository.Neo4jRepository;
  6. import org.springframework.data.repository.query.Param;
  7. import org.springframework.stereotype.Repository;
  9. import java.util.List;
  11. @Repository
  12. public interface PersonRepository extends Neo4jRepository<Person,Long> {
  13.      /** 查看money 大于指定值的Person 列表 */
  14.      //@Query("match(p:Person) where p.money>{0} return p")
  15.      @Query("match(p:Person) where p.money>{money} return p")
  16.      List<Person>   personList(@Param("money") double money);
  18.      /** 指定开始的名字 和 结束的名字 查询最短路径  限定深度为4以层包含4*/
  19.      @Query("match p=shortestPath((person:Person{name:{startName}})-[*1..4]-(person2:Person {name:{endName}})) return p")
  20.      List<Person>   shortestPath(@Param("startName") String startName,@Param("endName") String endName);
  21.      @Query("match p =(person:Person {name:{name}})-[*1..2]-(:Person) return p")
  22.      List<Person>   personListDept(@Param("name") String name);
  23. }

配置文件 application.yml

  1. spring:
  2.   data:
  3.     neo4j:
  4.       username: neo4j
  5.       password: 123456
  6.       uri:  bolt://192.168.211.133:7687

编写服务类

  1. package com.lagou.service;
  3. import com.lagou.bean.Person;
  4. import com.lagou.repository.PersonRepository;
  5. import org.springframework.beans.factory.annotation.Autowired;
  6. import org.springframework.stereotype.Service;
  8. import java.util.ArrayList;
  9. import java.util.List;
  11. @Service("personService")
  12. public class Neo4jPersonService {
  13.     @Autowired
  14.     private PersonRepository personRepository;
  15.     public List<Person>  getAll(){
  16.         List<Person>  datas = new ArrayList<>();
  17.         personRepository.findAll().forEach(person -> datas.add(person));
  18.         return  datas;
  19.     }
  20.     public  Person  save(Person person){
  21.         return  personRepository.save(person);
  22.     }
  23.     public  List<Person>  personList(double money){
  24.         return  personRepository.personList(money);
  25.     }
  27.     public List<Person> shortestPath(String startName,String endName){
  28.         return personRepository.shortestPath(startName,endName);
  29.     }
  30.     public  List<Person> personListDept(String name){
  31.         return  personRepository.personListDept(name);
  32.     }
  35. }

编写测试类

  1. package com.lagou;
  3. import com.lagou.bean.Person;
  4. import com.lagou.service.Neo4jPersonService;
  5. import org.springframework.boot.SpringApplication;
  6. import org.springframework.boot.autoconfigure.SpringBootApplication;
  7. import org.springframework.context.ApplicationContext;
  9. import java.util.List;
  11. @SpringBootApplication
  12. public class Neo4jBootAppMain {
  13.     public static void main(String[] args) {
  14.         ApplicationContext  applicationContext = SpringApplication.run(Neo4jBootAppMain.class,args);
  15.         Neo4jPersonService  personService = applicationContext.getBean("personService",Neo4jPersonService.class);
  16.         Person  person = new Person();
  17.         person.setName("testboot");
  18.         person.setMoney(12345.45);
  19.         person.setCharacter("A");
  20.         person.setAge(11);
  21.         Person p1 = personService.save(person);
  22.         System.out.println(p1);
  23.         System.out.println(personService.getAll());
  24.         List<Person>  personList = personService.personList(1000);
  25.         System.out.println(personList);
  26.         List<Person>  personList2 = personService.shortestPath("王启年","九品射手燕小乙");
  27.         System.out.println(personList2);
  28.         List<Person> personList3 = personService.personListDept("范闲");
  29.         for (Person pe:personList3){
  30.             System.out.println(pe);
  31.         }
  32.     }
  33. }