springboot-jpa多數據源

時間 2019-12-02

原文原文鏈接

Maven依賴

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

application.yml

spring:
  datasource: #默認type：HikariDataSource 號稱java最快的鏈接池
    primary:
      jdbcUrl: jdbc:mysql://127.0.0.1:3306/heyday?useUnicode=true&characterEncoding=utf8
      username: root
      password: root
      maximum-pool-size: 30
      minimum-idle: 5
    secondary:
      jdbcUrl: jdbc:mysql://127.0.0.1:3306/heyday2?useUnicode=true&characterEncoding=utf8
      username: root
      password: root
      maximum-pool-size: 30
      minimum-idle: 5

  jpa:
    hibernate:
      naming:
        physical-strategy:    org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy
        implicit-strategy: org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy

Java配置類

DataSourceConfig

package com.jinjian.demo.config;

import com.zaxxer.hikari.HikariDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import javax.sql.DataSource;

@Configuration
public class DataSourceConfig {


    @Bean("primaryDataSource")
    @Primary
    @ConfigurationProperties("spring.datasource.primary")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().type(HikariDataSource.class).build();  //返回的DataSource對象會被@ConfigurationProperties進行屬性注入
    }

    @Bean("secondaryDataSource")
    @ConfigurationProperties("spring.datasource.secondary")
    public DataSource secondaryDataSource() {
        return DataSourceBuilder.create().type(HikariDataSource.class).build();
    }

}

PrimaryConfig

package com.jinjian.demo.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.sql.DataSource;
import java.util.Map;


@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactoryPrimary",
        transactionManagerRef="transactionManagerPrimary",
        basePackages= { "com.jinjian.demo.repository.primary" })
public class PrimaryConfig {

    @Autowired
    @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;

    @Autowired private JpaProperties jpaProperties; //Jpa自帶的一個讀取jpa屬性的類

    @Bean("entityManagerFactoryPrimary")
    @Primary
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary() {

        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter(); 
        vendorAdapter.setGenerateDdl(true); //hibernate基本配置
        vendorAdapter.setDatabase(Database.MYSQL);
        vendorAdapter.setShowSql(true);

        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(vendorAdapter);
        factory.setPackagesToScan("com.jinjian.demo.pojo.primary"); //實體掃描
        factory.setDataSource(primaryDataSource); 

        Map<String, Object> hibernateProperties = jpaProperties.getHibernateProperties(new HibernateSettings());
        factory.setJpaPropertyMap(hibernateProperties);  //主要目的：讀取application.yml的naming-strategy,並設置進去，否則實體屬性與表字段之間沒法進行駝峯->下劃線的自動轉換,原本默認就是自動轉換的。可是你是配的多個自定義數據源，spring特性之一，一旦自定義，默認不生效，瞭解一下...
　　     
        return factory;

    }


    @Bean("transactionManagerPrimary")
    @Primary 
    public PlatformTransactionManager transactionManagerPrimary() { //事務管理器：事務不能跨數據源，跨數據源，事務是不生效的。使用事務時，最好要指明使用哪一個事務管理器，否則就會默認使用primary修飾的事務管理器

        JpaTransactionManager txManager = new JpaTransactionManager();
        txManager.setEntityManagerFactory(entityManagerFactoryPrimary().getObject());
        return txManager;

    }




}

SecondaryConfigjava

package com.jinjian.demo.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.sql.DataSource;
import java.util.Map;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactorySecondary",
        transactionManagerRef="transactionManagerSecondary",
        basePackages= { "com.jinjian.demo.repository.secondary" })
public class SecondaryConfig {

    @Autowired
    @Qualifier("secondaryDataSource")
    private DataSource secondaryDataSource;

    @Autowired
    private JpaProperties jpaProperties;

    @Bean("entityManagerFactorySecondary")
    public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary() {
        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        vendorAdapter.setGenerateDdl(true);
        vendorAdapter.setDatabase(Database.MYSQL);
        vendorAdapter.setShowSql(true);

        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(vendorAdapter);
        factory.setPackagesToScan("com.jinjian.demo.pojo.secondary");
        factory.setDataSource(secondaryDataSource);

        Map<String, Object> hibernateProperties = jpaProperties.getHibernateProperties(new HibernateSettings());
        factory.setJpaPropertyMap(hibernateProperties);
        return factory;
    }


    @Bean("transactionManagerSecondary")
    public JpaTransactionManager transactionManagerSecondary() {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactorySecondary().getObject());
        return transactionManager;
    }
}

POJO與Repository包結構

　mysql

如何在service中使用

package com.jinjian.demo.service;

import com.jinjian.demo.pojo.secondary.Tclient;
import com.jinjian.demo.repository.secondary.TclientRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
public class TclientService {

    @Autowired
    private TclientRepository tclientRepository;

    @Transactional("transactionManagerSecondary") //非主事務管理器，必須寫明用的是哪一個，否則用的別就是默認數據源的事務管理器，就無效。
    public void addTclient(Tclient tclient){
        tclientRepository.delete(tclient);
        if (1 == 1){
            throw new RuntimeException("測試");
        }
        tclientRepository.save(tclient);
    }
}