Spring Boot integrates with a number of data technologies, both SQL and NoSQL.
SQL Databases
Spring Data provides an additional level of functionality: creating Repository
implementations directly from interfaces and using conventions to generate queries from your method names.
The spring-boot-starter-data-jpa
POM provides a quick way to get started. It provides the following key dependencies:
- Hibernate: One of the most popular JPA implementations.
- Spring Data JPA: Helps you to implement JPA-based repositories.
- Spring ORM: Core ORM support from the Spring Framework.
A typical entity class resembles the following example:
代码语言:javascript复制import java.io.Serializable;
import jakarta.persistence.Column;
import jakarta.persistence.Entity;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.Id;
@Entity
public class City implements Serializable {
@Id
@GeneratedValue
private Long id;
@Column(nullable = false)
private String name;
@Column(nullable = false)
private String state;
// ... additional members, often include @OneToMany mappings
protected City() {
// no-args constructor required by JPA spec
// this one is protected since it should not be used directly
}
public City(String name, String state) {
this.name = name;
this.state = state;
}
public String getName() {
return this.name;
}
public String getState() {
return this.state;
}
// ... etc
}
Working with NoSQL Technologies
Redis
Redis is a cache, message broker, and richly-featured key-value store. Spring Boot offers basic auto-configuration for the Lettuceand Jedis client libraries and the abstractions on top of them provided by Spring Data Redis.
By default, the instance tries to connect to a Redis server at localhost:6379
.
spring.data.redis.host=localhost
spring.data.redis.port=6379
spring.data.redis.database=0
spring.data.redis.username=user
spring.data.redis.password=secret
MongoDB
The auto-configured MongoClient
is created using a MongoClientSettings
bean.
spring.data.mongodb.host=mongoserver1.example.com
spring.data.mongodb.port=27017
spring.data.mongodb.additional-hosts[0]=mongoserver2.example.com:23456
spring.data.mongodb.database=test
spring.data.mongodb.username=user
spring.data.mongodb.password=secret
Elasticsearch
Spring Boot supports several clients:
- The official low-level REST client
- The official Java API client
- The
ReactiveElasticsearchClient
provided by Spring Data Elasticsearch
spring.elasticsearch.uris=https://search.example.com:9200
spring.elasticsearch.socket-timeout=10s
spring.elasticsearch.username=user
spring.elasticsearch.password=secret
InfluxDB
InfluxDB is an open-source time series database optimized for fast, high-availability storage and retrieval of time series data in fields such as operations monitoring, application metrics, Internet-of-Things sensor data, and real-time analytics.
代码语言:javascript复制spring.influx.url=https://172.0.0.1:8086
参考资料: https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#data