spring boot 2.0 neo4j 使用

参考文档

　　官方文档

http://spring.io/projects/spring-data-neo4j#learn
https://docs.spring.io/spring-data/neo4j/docs/5.1.2.RELEASE/reference/html/
https://neo4j.com/docs/
https://neo4j.com/docs/developer-manual/current/

　　第三方使用文档

https://blog.csdn.net/appleyk/article/category/7408344 系列文档
https://blog.csdn.net/u013946356/article/details/81739079

　　中文手册（比较滞后）

https://www.w3cschool.cn/neo4j/

安装 maven 包

<dependency>
　　<groupId>org.neo4j</groupId>
　　<artifactId>neo4j-ogm-http-driver</artifactId>
　　<version>3.1.4</version>
</dependency>

<dependency>
　　<groupId>org.springframework.boot</groupId>
　　<artifactId>spring-boot-starter-data-neo4j</artifactId>
　　<version>2.1.0.RELEASE</version>
</dependency>

添加 neo4j 配置

application.yml

spring:
  data:
    neo4j:
      username: neo4j
      password: 1234
      uri: http://172.16.235.175:7474

添加配置类

@Configuration
@EnableNeo4jRepositories(basePackages = "com.example.demo.repository")
@EnableTransactionManagement
public class Neo4jConfig {

    @Value("${spring.data.neo4j.uri}")
    private String databaseUrl;

    @Value("${spring.data.neo4j.username}")
    private String userName;

    @Value("${spring.data.neo4j.password}")
    private String password;

    @Bean
    public SessionFactory sessionFactory() {
        org.neo4j.ogm.config.Configuration configuration = new org.neo4j.ogm.config.Configuration.Builder()
                .uri(databaseUrl)
                .credentials(userName, password)
                .build();
        return new SessionFactory(configuration, "com.example.demo.entity");
    }

    @Bean
    public Neo4jTransactionManager transactionManager() {
        return new Neo4jTransactionManager(sessionFactory());
    }
}

添加 Neo4j 节点类

@NodeEntity
public class SGNode {
    private Long count;
    private Long error;
    private Double max;
    private Double min;

    /**
     * Neo4j会分配的ID（节点唯一标识 当前类中有效）
     */
    @Id
    @GeneratedValue
    private Long id;

    private String name;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    @Relationship(type = "call")
    private List<CallRelation> calls;

    public SGNode() {
        count = 0L;
        error = 0L;
        max = 0.0;
        min = 0.0;
        calls = new ArrayList<>();
    }

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

    public Long getCount() {
        return count;
    }

    public void setCount(Long count) {
        this.count = count;
    }

    public Long getError() {
        return error;
    }

    public void setError(Long error) {
        this.error = error;
    }

    public Double getMax() {
        return max;
    }

    public void setMax(Double max) {
        this.max = max;
    }

    public Double getMin() {
        return min;
    }

    public void setMin(Double min) {
        this.min = min;
    }

    public List<CallRelation> getCalls() {
        return calls;
    }

    public void setCalls(List<CallRelation> calls) {
        this.calls = calls;
    }

    public void addCalls(SGNode node, Long count) {
        CallRelation relation = new CallRelation(this, node, count);
        this.calls.add(relation);
    }
}

添加 Neo4j 关系类

@RelationshipEntity(type = "call")
public class CallRelation {

    public CallRelation() {
        this.name = "call";
    }


    public CallRelation(SGNode start, SGNode end, Long count) {
        this();
        this.startNode = start;
        this.endNode = end;
        this.count = count;
    }

    /**
     * Neo4j会分配的ID（节点唯一标识 当前类中有效）
     */
    @Id
    @GeneratedValue
    private Long id;

    private String name;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    /**
     * 定义关系的起始节点 == StartNode
     */

    @StartNode
    private SGNode startNode;

    /**
     * 定义关系的终止节点 == EndNode
     */

    @EndNode
    private SGNode endNode;


    /**
     * 定义关系的属性
     */

    @Property(name = "count")
    private Long count;

    public SGNode getStartNode() {
        return startNode;
    }

    public void setStartNode(SGNode startNode) {
        this.startNode = startNode;
    }

    public SGNode getEndNode() {
        return endNode;
    }

    public void setEndNode(SGNode endNode) {
        this.endNode = endNode;
    }

    public Long getCount() {
        return count;
    }

    public void setCount(Long count) {
        this.count = count;
    }
}

添加 Reponsitory

@Repository
public interface SGNodeReponsitory extends Neo4jRepository<SGNode, Long> {
　　// 此处用法可见 https://docs.spring.io/spring-data/neo4j/docs/5.1.2.RELEASE/reference/html/#_query_methods
    SGNode findByName(@Param("name") String name);
}

使用 Demo

@RestController
@RequestMapping("/sg")
public class SGNodeController {

    @Autowired
    SGNodeReponsitory sgNodeReponsitory;

    @DeleteMapping("/delete")
    public String delete() {
        sgNodeReponsitory.deleteAll();
        return "OK";
    }

    @GetMapping("/add")
    public String add() {
        addNodes();
        return "OK";
    }

    @GetMapping("/get")
    public String relation() {
        SGNode node = sgNodeReponsitory.findByName("tsp");
        List<Long> ids = new ArrayList<>();
        ids.add(node.getId());
        Iterable<SGNode> result = sgNodeReponsitory.findAllById(ids, 1);
        return "OK";
    }


    private void addNodes() {
        sgNodeReponsitory.deleteAll();

        List<SGNode> list = new ArrayList<>();

        SGNode node = new SGNode("tsp");
        list.add(node);

        for (Integer i = 1; i <= 10; i++) {
            node = new SGNode("tsp" + i);
            node.setCount(new Random().nextLong());
            node.setError(new Random().nextLong());
            node.setMax(new Random().nextDouble());
            node.setMin(new Random().nextDouble());
            list.add(node);
        }

        sgNodeReponsitory.saveAll(list);

        SGNode start = sgNodeReponsitory.findByName("tsp1");
        SGNode end = sgNodeReponsitory.findByName("tsp");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp2");
        end = sgNodeReponsitory.findByName("tsp");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp9");
        end = sgNodeReponsitory.findByName("tsp7");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp7");
        end = sgNodeReponsitory.findByName("tsp2");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp2");
        end = sgNodeReponsitory.findByName("tsp8");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp");
        end = sgNodeReponsitory.findByName("tsp3");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp");
        end = sgNodeReponsitory.findByName("tsp4");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp6");
        end = sgNodeReponsitory.findByName("tsp3");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp3");
        end = sgNodeReponsitory.findByName("tsp5");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);

        start = sgNodeReponsitory.findByName("tsp5");
        end = sgNodeReponsitory.findByName("tsp10");
        start.addCalls(end, new Random().nextLong());
        sgNodeReponsitory.save(start);
    }
}