Hello World 之Spring Boot 调用图数据库Neo4j
时间：2022-03-15 15:03
- 明日歌
- [清]钱鹤滩
- 明日复明日，明日何其多！
- 我生待明日，万事成蹉跎
spring.data.neo4j.username=neo4j
spring.data.neo4j.password=helloworld
application.yml版：
- spring:
- data:
- neo4j:
- username: neo4j
- password: helloworld
@NodeEntity
public class Legend {
@Id @GeneratedValue private Long id;
private String name;
private Legend() {
// Empty constructor required as of Neo4j API 2.0.5
};
public Legend(String name) {
this.name = name;
}
/**
* Neo4j doesn‘t REALLY have bi-directional relationships. It just means when querying
* to ignore the direction of the relationship.
* https://dzone.com/articles/modelling-data-neo4j
*/
@Relationship(type = "FANS", direction = Relationship.UNDIRECTED)
public Set<Legend> fans;
public void fansWith(Legend legend) {
if (fans == null) {
fans = new HashSet<>();
}
fans.add(legend);
}
public String toString() {
//java 8 stream and optional
return this.name + "‘s fans => "
+ Optional.ofNullable(this.fans).orElse(
Collections.emptySet()).stream()
.map(Legend::getName)
.collect(Collectors.toList());
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
