spring boot 已经支持多数据源配置了,无需网上好多那些编写什么类的,特别麻烦,看看如下解决方案,官方的,放心!
1.首先定义数据源配置
#=====================multiple database config============================
#ds1
first.datasource.url=jdbc:mysql://localhost/test?characterencoding=utf8&usessl=true
first.datasource.username=root
first.datasource.password=123456
first.datasource.driver-class-name=com.mysql.jdbc.driver
first.datasource.type=org.apache.tomcat.jdbc.pool.datasource
first.datasource.max-wait=10000
first.datasource.max-active=200
first.datasource.test-on-borrow=true
first.datasource.initial-size=10
#ds2
second.datasource.url=jdbc:mysql://localhost/test2?characterencoding=utf8&usessl=true
second.datasource.username=root
second.datasource.password=123456
second.datasource.driver-class-name=com.mysql.jdbc.driver
second.datasource.type=org.apache.tomcat.jdbc.pool.datasource
second.datasource.max-wait=10000
second.datasource.max-active=200
second.datasource.test-on-borrow=true
second.datasource.initial-size=10
#=====================jpa config================================
#实体类维护数据库表结构的具体行为:update/create/create-drop/validate/none
spring.jpa.hibernate.ddl-auto=none
#打印sql语句
spring.jpa.show-sql=true
#格式化输出的json字符串
spring.jackson.serialization.indent_output=true
2.配置ds1的相关注入对象和启用jpa支持
/**
* created by hdwang on 2017-06-16.
* 第一个数据源配置
* if you are using spring data, you need to configure @enablejparepositories */@configuration
@enabletransactionmanagement
@enablejparepositories(basepackages = com.hdwang.dao.datajpa.firstds,entitymanagerfactoryref = firstentitymanagerfactory,transactionmanagerref=firsttransactionmanager)public class firstdsconfig {/** * 数据源配置对象
* primary 表示默认的对象,autowire可注入,不是默认的得明确名称注入
* @return */@bean
@primary
@configurationproperties(first.datasource)public datasourceproperties firstdatasourceproperties() {return new datasourceproperties();
}/** * 数据源对象
* @return */@bean
@primary
@configurationproperties(first.datasource)public datasource firstdatasource() {return firstdatasourceproperties().initializedatasourcebuilder().build();
}/** * 实体管理对象
* @param builder 由spring注入这个对象,首先根据type注入(多个就取声明@primary的对象),否则根据name注入
* @return */@bean
@primarypublic localcontainerentitymanagerfactorybean firstentitymanagerfactory(
entitymanagerfactorybuilder builder) {return builder
.datasource(firstdatasource())
.packages(com.hdwang.entity.dbfirst)
.persistenceunit(firstds)
.build();
}/** * 事务管理对象
* @return */@bean(name = firsttransactionmanager)
@primarypublic platformtransactionmanager transactionmanager(entitymanagerfactory emf){
jpatransactionmanager transactionmanager = new jpatransactionmanager();
transactionmanager.setentitymanagerfactory(emf);return transactionmanager;
}
@bean
@primarypublic jdbctemplate jdbctemplate(){return new jdbctemplate(firstdatasource());
}
@bean
@primarypublic transactiontemplate transactiontemplate(platformtransactionmanager platformtransactionmanager){return new transactiontemplate(platformtransactionmanager);
}
}
相关知识点:
1.使用@bean可以创建一个bean对象交给spring容器管理
2.@bean创建的bean对象的名称默认为方法名,也可以指定
3.@bean方法参数表示,接收一个bean对象,默认按照type类型接收注入的对象,若要修改为byname方式,可以使用@qualifier注解注入准确的对象
4.@primary表示该bean为此类型的默认bean,在其他地方引用的时候用@autowired即可按照类型注入,不受同类型多个对象影响
5.enablejparepositories表示启用spring data jpa的支持,也就是jpa的新使用方式,注意basepackages指的事 @repository接口的所在包位置,可配置多个
其他注解就不清楚了!
2.配置ds2的相关注入对象和启用jpa支持
@configuration
@enabletransactionmanagement
@enablejparepositories(basepackages = com.hdwang.dao.datajpa.secondds, entitymanagerfactoryref = secondentitymanagerfactory,transactionmanagerref = secondtransactionmanager)public class seconddsconfig {
@bean
@configurationproperties(second.datasource)public datasourceproperties seconddatasourceproperties() {return new datasourceproperties();
}
@bean
@configurationproperties(second.datasource)public datasource seconddatasource() {return seconddatasourceproperties().initializedatasourcebuilder().build();
}/** * 实体管理对象
* @param builder 由spring注入这个对象,首先根据type注入(多个就取声明@primary的对象),否则根据name注入
* @return */@beanpublic localcontainerentitymanagerfactorybean secondentitymanagerfactory(
entitymanagerfactorybuilder builder) {return builder
.datasource(seconddatasource())
.packages(com.hdwang.entity.dbsecond)
.persistenceunit(secondds)
.build();
}/** * 事物管理对象
* @param secondentitymanagerfactory 实体管理工厂对象(按照名称注入)
* @return 平台事物管理器 */@bean(name = secondtransactionmanager)public platformtransactionmanager transactionmanager(@qualifier(secondentitymanagerfactory)localcontainerentitymanagerfactorybean secondentitymanagerfactory){
jpatransactionmanager transactionmanager = new jpatransactionmanager();
transactionmanager.setentitymanagerfactory(secondentitymanagerfactory.getobject());return transactionmanager;
}
@bean(name=jdbctemplate2)public jdbctemplate jdbctemplate(){return new jdbctemplate(seconddatasource());
}
@bean(name = transactiontemplate2)public transactiontemplate transactiontemplate(@qualifier(secondtransactionmanager)platformtransactionmanager transactionmanager){return new transactiontemplate(transactionmanager);
}
}
3.repository数据持久层
package com.hdwang.dao.datajpa.firstds;
@repositorypublic interface userrepository extends jparepository<user, integer> {/** * spring data jpa 会自动注入实现(根据方法命名规范)
* @return */user findbynumber(string number);
@modifying
@query(delete from user u where u.id = :id)void deleteuser(@param(id)int id);
}
package com.hdwang.dao.datajpa.secondds;
@repositorypublic interface orderrepository extends jparepository<order, integer> {/** * spring data jpa 会自动注入实现(根据方法命名规范)
* @return */user findbynumber(string number);
@modifying
@query(delete from order o where o.id = :id)void deleteuser(@param(id) int id);
}
上面两个接口分属两个数据源,在@enablejparepositories配置好后,这里就可以正确操作相应的数据源了
4.service服务层,注意事物(接口我就不贴了)
@service@transactional(firsttransactionmanager)public class userserviceimpl implements userservice {
@autowiredprivate userrepository userrepository;
@overridepublic user findbyid(int id) {return this.userrepository.findone(id);
}
@overridepublic user findbynumber(string number) {return this.userrepository.findbynumber(number);
}
@overridepublic list<user> findalluserbypage(int page,int size) {
pageable pageable = new pagerequest(page, size);
page<user> users = this.userrepository.findall(pageable);return users.getcontent();
}
@overridepublic user updateuser(user user,boolean throwex) {
user usernew = this.userrepository.save(user);if(throwex){throw new runtimeexception(throw a ex);
}return usernew;
}
@overridepublic void deleteuser(int id) {this.userrepository.deleteuser(id);
}
}
@service@transactional(secondtransactionmanager)public class orderserviceimpl implements orderservice {
@autowiredprivate orderrepository orderrepository;
@overridepublic order findbyid(int id) {return this.orderrepository.findone(id);
}
@overridepublic order updateorder(order order, boolean throwex) {
order ordernew = this.orderrepository.save(order);if(throwex){throw new runtimeexception(throw a ex);
}return ordernew;
}
}
知识扩展
1.如果采用传统jpa方式,@enablejparepositories无需配置,配置了也无影响。实现方式如下:
ds1相关daoimpl
@persistencecontext
private entitymanager entitymanager;
ds2相关daoimpl
@persistencecontext(unitname = secondds)
private entitymanager entitymanager;
因为ds1的entitymanger声明了@primary,所以无需指明unitname,ds2必须指明。注入了准确的entitymanager,就可以直接拿来操作数据库了。service层和上面一样的,@transactional(xxxmanager)指明事物管理器即可!
2.采用jdbctemplate方式,直接注入到service层对象即可,so easy!
@autowired
private jdbctemplate jdbctemplate;
@autowired
private transactiontemplate transactiontemplate;
@resource(name=jdbctemplate2)
private jdbctemplate jdbctemplate2;
@resource(name=transactiontemplate2)
private transactiontemplate transactiontemplate2;
好了,spring boot 多数据源,完美解决! 而且三种数据库操作方法均支持,包括事物。已经经过实践证明了! 这是官方给出的最佳实践,只是官方文档没写细。导致整整坑了我几天。至此,spring boot框架的使用就告一段落了!
以上就是java之spring boot 1.5.4 配置多数据源的详细内容。