Neo4J 安装&常见语句操作&项目中的集成应用&复杂查询（@Query注解和自定义Match）

I 安装Neo4J
1 准备工作

    1.1 下载安装包--bin--Neo4J-ce.exe，执行Start

1.2 访问 http://localhos:7474/browser/

II 常见语句操作

删除节点

MATCH(n:City) DETACH DELETE nMATCH(n:City {name="Wuhan"}) DETACH DELETE nSTART n = node(1) DELETE n

删除关系、节点关系

match (n)-[r:created]-()  detach delete rmatch(o:Organ {organId:"1000"})-[r:ORGAN_ACCOUNT]->(c:Account{countId:"1"})detach delete rmatch(o:Organ {organId:"1000"})-[r:ORGAN_ACCOUNT]->(c:Account{countId:"1"})detach delete r，o,c

查看节点

MATCH(n:City) DETACH RETURN n

查看关系

match (n)-[r:created]-()  RETURN r

创建结点：create (:Person {name:"张三"})，创建一个名为张三的节点；

create (a:Equip{equipSn:'SC1',equipStatus:'1'})create (c:Account{countId:'1',Name:'CJ1',userName:'CJ去名称'})

创建结点关系：

create (n:Equip {equipSn:"SC1"})-[r:equip_Customer {bindStatus:"1"}]->(c:Customer {Id:"adminId",Name:"chenJ"}) return n,r,c;

条件查询：

MATCH (n:BdEquipmentInfo)-[r:ISERVER_CUSTOMER]->(c:CfCustomer )WHERE 1 = 1 and n.equipmentSn= "SC1" And c.customerName =~ '.*nJAdmin.*' and r.bindStatus = '1' RETURN c ;

修改属性值，给默认的根节点添加name,ID属性，便于查询

start a = node(*) where a.name="a" set a.name="A" return a,a.name ; start n=node(0) set n.name="Root",n.ID="001" 

创建多个节点数据，多个元素间用逗号或者用create分开：

create (a:Person {name:"jiaj",born:2003})-[r:ACTED_IN {roles:["student"]}]->(m:School {name:"CDLG",address:"chengdu"})create (d:Person {name:"weiw",born:2001})-[:DIRECTED]->(m)return a,d,r,m;

创建关系【在id=1和2的2个节点间】

CREATE (a:node(1))-[:ACTED_IN { roles: "Forrest"}]->(b:node(2))

官网： http://neo4j.com/docs/developer-manual/current/cypher/clauses/match/


III 项目中的集成应用

1 定义结点、关系（@NodeEntity、@RelationshipEntity）

结点关系图：

package com.domain.entity;@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")@NodeEntitypublic class BdApp{    @GraphId    private Long id;    private String appId;    private String appName;    private String appType;    private String appClassId;    //}@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")@NodeEntitypublic class BdAppVer{    @GraphId    private Long id;    private String appVerId;    private String appVerNum;    //}package com.domain.relationship;@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")@RelationshipEntity(type = "APP_VER")public class AppVerRelationship {    @GraphId    private Long id;    @StartNode    private BdApp bdApp;    @EndNode    private BdAppVer bdAppVer;    private String memo;    //}

**************************************

2 定义结点、关系持久化层

2.1 APP 结点 Code：

package com.mapper.entity;import org.springframework.data.neo4j.repository.GraphRepository;import org.springframework.stereotype.Repository;@Repositorypublic interface BdAppRepository extends GraphRepository<BdApp> { //1 可自动继承neo4j.repository.GraphRepository父类封装的各方法 //2自定义方法  BdApp findByAppId(String appId);}

附：结点持久化层的 继承关系图

2.2 AppVer结点Code

package com.mapper.relationship@Repositorypublic interface BdAppVerRepository extends GraphRepository<BdAppVer> {    //3Query自定义属性模糊与精确查询,appVerName= ".*XXX.*"    @Query("MATCH (bdAppVer:BdAppVer) " +            "WHERE bdAppVer.appId={appId} AND bdAppVer.appVerName =~ {appVerName} " +            "RETURN bdAppVer ORDER BY bdAppVer.appVerNum DESC ")    List<BdAppVer> queryBdAppVer(String appId, String appVerName);}

2.3 关系AppVerRepository Code

@Repositorypublic interfaceAppVerRepositoryextendsGraphRepository<AppVerRelationship> {//同结点原理一致}

3 定义结点、关系Service层

3.1 BdAppService：

public interface BdAppService {    /**     * 创建BdApp      */    BdApp createBdApp(BdApp bdApp);     /**     * 创建BdAppVer 和 关系AppVerRelationship      */    BdAppVer createBdAppVer(String appId,BdAppVer bdAppVer);}

Impl：

@Service@Transactionalpublic class BdAppServiceImpl implements BdAppService {   @Autowired   private BdAppRepository bdAppRepository;   @Autowired   private BdAppVerRepository bdAppVerRepository;   @Autowired   private AppVerRepository appVerRepository;//关系Repository    @Override    public BdApp createBdApp(BdApp bdApp) {    //bdApp.setAppId(UUID.randomUUID().toString());    bdAppRepository.save(bdApp);    return bdApp;    }    @Overridepublic BdAppVer createBdAppVer(String appId, BdAppVer bdAppVer) {    BdApp bdApp = bdAppRepository.findByAppId(appId);    bdAppVer.setAppId(appId);    bdAppVerRepository.save(bdAppVer);    //建立关系    AppVerRelationship appVerRelationship = new    AppVerRelationship();appVerRelationship.setBdApp(bdApp);appVerRelationship.setBdAppVer(bdAppVer);appVerRelationship.setMemo("");appVerRepository.save(appVerRelationship);}

3.2 BdAppVerService&BdAppVerServiceImpl同上

4 SpringJUnit4测试 结点/结点关系的CURD

4.1 定义环境（ComponentScan、Configuration和初始化neo4j Jdbc）

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;import org.springframework.boot.autoconfigure.domain.EntityScan;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;import org.springframework.data.neo4j.repository.config.EnableNeo4jRepositories;import org.springframework.transaction.annotation.EnableTransactionManagement;@EnableAutoConfiguration@EnableNeo4jRepositories(basePackages = {"com.mapper.entity.",        "com.mapper.relationship."})@EntityScan(basePackages = {"com.domain."})@EnableTransactionManagement@ComponentScan@Configurationpublic class CoreConfig{    @Bean    public org.neo4j.ogm.config.Configuration getConfiguration(){        org.neo4j.ogm.config.Configuration config = new org.neo4j.ogm.config.Configuration();        config.driverConfiguration()             .setDriverClassName("org.neo4j.ogm.drivers.http.driver.HttpDriver")                .setURI("http://neo4j:neo4j@localhost:7474");        return config;    }}

4.2 测试类：

import org.junit.Test;import org.junit.runner.RunWith;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.test.context.ContextConfiguration;import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;//应用模块测试@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration(classes=CoreConfig.class)public class BdAppServiceTest {    @Autowired    public BdAppService bdAppService;    @Test    public void createBdAppTest(){       BdApp bdApp = new BdApp();       bdApp.setAppId("CJ1");       bdApp初始化值Set       bdAppService.createBdApp(bdApp);   }    @Test    public void createBdAppVerAndRelationshipTest(){       String appId = "CJ1";       BdAppVer  appVer = new BdApp();       BdAppVer  初始化值Set       bdAppService.createBdAppVer(appId ,bdApp);   }}

5 实现复杂查询（如多条件分页查询&结点、关系组合查询等

5.1 Match执行复杂语句方式，执行@Query实现

5.2 自定义持久层Dao实现
**********************************************************************************
5.1 Code:

1 实体、关系定义：

实体:

@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")@NodeEntitypublic class Packcode{    @GraphId    private Long id;    private String packcodeNo;//当前包编号    private String parentPackcodeNo;//父（上级）包编号    private String packName;    @Relationship(type= "Pc_LINK_Pc")    private Set<PackCodeLinkPackRship> packCodeLinkPacks; }

关系：

@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")@RelationshipEntity(type = "Pc_LINK_Pc")@QueryResultpublic class PackCodeLinkPackRship {    @StartNode    private Packcode bdPackcode;    @EndNode    private Packcode subBdPackcode;    @GraphId    private Long id;    private String bindStatus;。。。}

2 Cypher语句查询实现

//2.1 获取packcodeNo 包所有子包（即下属树结点信息）@Query(" MATCH p=(p:Packcode)-[r:Pc_LINK_Pc*0..]->(subP:Packcode)  " +        " WHERE p.packcodeNo = {packcodeNo} " +        " RETURN p")List<Packcode> loadPackcodeSubTree(@Param("packcodeNo") String packcodeNo);即：MATCH p=(p:Packcode)-[r:Pc_LINK_Pc*0..]->(subP:Packcode)WHERE p.packcodeNo = '1' RETURN p;*********************************************************//2.2获取packcodeNo 包所有父包且关系bindStatus=1@Query(" MATCH p=(s:Packcode)-[rp:Pc_LINK_Pc*0..]->(subP:Packcode)  " +       " WHERE subP.packcodeNo = {packcodeNo} and all( x in rp where x.bindStatus= {bindStatus}  ) "+       " RETURN  p ")List<Packcode> findAllParentPackcodeByPackcodeNoAndBindStatus(@Param("packcodeNo")String packcodeNo,@Param("bindStatus") String bindStatus);即：MATCH p=(s:Packcode)-[rp:Pc_LINK_Pc*0..]->(e:BdPackcode)  WHERE e.packcodeNo = '3Sub' and all( x in rp where x.bindStatus='1'  )  RETURN  p;

***********************************************************************************

I) 多条件查询（未分页）

1 定义App Dao接口

package com.mapper.neo4jdao.model;public interface BdAppDao {    List<BdApp> queryBdAppByPerproty(BdApp bdApp);}

2 实现App Dao实现层

package com.mapper.neo4jdao.model.Impl;@Repositorypublic class BdAppDaoImpl implements BdAppDao {    @Autowired    Session session;//查询前缀private static final String QUERY_PREFFIX = "MATCH (bdApp:BdApp) ";private static final String QUERY_WHERE = " WHERE  1 = 1 ";@Overridepublic List<BdApp> queryBdAppByPerproty(BdApp bdApp) {    Map<String, String> params = new HashMap<>();    String cypher = this.getListCypher(bdApp, params);    if (StringUtils.isEmpty(cypher)) return null;    Iterable<BdApp> its = session.query(BdApp.class, cypher, params);    if (its == null) return null;    List<BdApp> results = new ArrayList<>();    its.forEach((v) -> results.add(v));    return results;}/** * 构造查询型号的cypher语句 * @param queryParams 查询对象 * @return 返回cypher语句 */private String getListCypher(BdApp domain, Map<String, String> queryParams) {    StringBuffer stringBuffer = new StringBuffer(QUERY_PREFFIX);    stringBuffer.append(QUERY_WHERE);    stringBuffer.append(midCypher(stringBuffer, domain, queryParams));    stringBuffer.append(" RETURN bdApp");    stringBuffer.append(" ORDER BY bdApp.appType,bdApp.appClassName,bdApp.appId ASC ");//(默认按照 类型、分类 、appid排序)    return stringBuffer.toString();}/** * @param queryParams * @return */private String midCypher(StringBuffer sb, BdApp domain, Map<String, String> queryParams) {    StringBuffer stringBuffer = new StringBuffer();    //多条件查询：类型APP_TYPE、分类 APP_CLASS_NAME、appid、名称APP_NAME、状态APP_STATUS    if (!StringUtils.isEmpty(domain.getAppType())) {        stringBuffer.append(" AND bdApp.appType = {aType}");        queryParams.put("aType", domain.getAppType());    }    if (!StringUtils.isEmpty(domain.getAppClassId())) {        stringBuffer.append(" AND bdApp.appClassId = {appCId}");        queryParams.put("appCId", domain.getAppClassId());    }    if (!StringUtils.isEmpty(domain.getAppId())) {        stringBuffer.append(" AND bdApp.appId = {aId}");        queryParams.put("aId", domain.getAppId());    }    if (!StringUtils.isEmpty(domain.getAppName())) {        stringBuffer.append(" AND bdApp.appName =~ {aName}");        queryParams.put("aName", ".*"+domain.getAppName()+"*.");    }    //状态APP_STATUS    if (!StringUtils.isEmpty(domain.getAppStatus())) {        stringBuffer.append(" AND bdApp.appStatus = {aStatus}");        queryParams.put("aStatus", domain.getAppStatus());    }    return stringBuffer.toString();}

II）多条件分页查询（注意：雷同部分略）

1 Dao层

package com.mapper.neo4jdao.model;public interface BdAppDao {   int getTotalBdApp(String cypher,Map<String,String> params);   PageResult getBdAppPage(BdApp domain,Integer currPage, Integer pagesize);}

2 Dao 实现层

package com.mapper.neo4jdao.model.Impl;@Repositorypublic class BdAppDaoImpl implements BdAppDao {    @Autowired    Session session;    //查询前缀    private static final String QUERY_PREFFIX = "MATCH (bdApp:BdApp) ";    private static final String QUERY_WHERE = " WHERE  1 = 1 ";    @Override    public int getTotalBdApp(String cypher,Map<String,String> params) {       return DaoUtil.getTotalNum(session,cypher,params);     }     @Override     public PageResult getBdAppPage(BdApp bdApp,Integer page, Integer pagesize) {        PageResult pr = new PageResult();        Map<String,String> params = new HashMap<>();        StringBuffer cypherbuf = new StringBuffer(this.midCypher(domain,params));//需要修改下        if(StringUtils.isEmpty(cypherbuf)){          return pr;        }        int totalnum = this.getTotalBdApp(cypherbuf+" RETURN count(c) as count",params);        pr.setToltalsize(totalnum);        pr.setPage(page);        pr.setPagesize(pagesize);        page = page==null|page<1?1:page;        pagesize = pagesize == null | pagesize <1 ? 10:pagesize;        int skip = (page-1)*(totalnum/pagesize);        int limit = pagesize;        cypherbuf.append(" RETURN c");        cypherbuf.append(" SKIP ");        cypherbuf.append(skip);        cypherbuf.append(" LIMIT ");        cypherbuf.append(limit);        Iterable<BdApp> its = session.query(BdApp.class,cypherbuf.toString(),params);        if(its==null)return pr;        List<BdApp> results = new ArrayList<>();        its.forEach((v)->results.add(v));        pr.addData(results);        return pr;    }}

3 分页基础类-DaoUtil，统计总记录数

public class DaoUtil {    private DaoUtil(){}    public static int getTotalNum(Session session,String cypher,Map<String,String> params){        Result result = session.query(cypher,params);        int totalnum = 0;        if(result==null)return totalnum;        Iterator<Map<String,Object>> its = result.iterator();        while (its.hasNext()){            Map<String,Object> ret =  its.next();            if(ret!=null){                Object nums = ret.getOrDefault("count",0);                if( nums != null ){                    totalnum = Integer.parseInt(nums.toString());                    break;                }            }        }        return totalnum;    }}