DB数据源之SpringBoot+MyBatis踏坑过程（七）手动使用Tomcat连接池
liuyuhang原创，未经允许禁止转载
系列目录连接
DB数据源之SpringBoot+Mybatis踏坑过程实录（一）
1.环境说明
springboot2.0以下版本，java7，myeclipse2017 C1，使用的是mySql数据库
pom
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>Tit</groupId>
<artifactId>FM</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging> <parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.3.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<dependencies> <!-- spring boot web -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency> <dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency> <dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-logging-juli</artifactId>
<version>7.0.62</version>
</dependency> <!-- 添加MySQL依赖 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- 添加JDBC依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<!-- mybaits基础依赖 -->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.0</version>
</dependency>
<!-- mybatis插件依赖 -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.1.1</version>
</dependency>
<!-- mapper依赖 -->
<dependency>
<groupId>tk.mybatis</groupId>
<artifactId>mapper</artifactId>
<version>3.3.7</version>
</dependency> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency> <!-- 热部署 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
<scope>true</scope>
</dependency>
<!-- end of 热部署 -->
</dependencies> <properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.7</java.version> <webVersion>3.0</webVersion>
</properties>
<build>
<finalName>FM</finalName>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin </artifactId>
</plugin>
</plugins> </build>
</project>
2.配置思路
- 确保类单例，使用构造器实例化的sqlSessionFactory只设置一次
- 提供getSqlSessionFactory获取sqlSessionFactory
- setSqlSessionFactory时初始化数据源，并设置连接池
- setSqlSessionFactory方法提供参数可对数据源进行更改，以确保数据源故障时可进行重新设置
3.所需类与结构
3.1.pom，略
3.2.DataConfig.java配置数据源获取SqlSessionFactory类
3.3.mapper.xml，略
3.4.HelloExample.java测试，略
3.5.AppRun.java，Springboot启动类，略
4.代码
DataConfig.java代码如下：
package com.FM.config; import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.tomcat.jdbc.pool.DataSource;
import org.apache.tomcat.jdbc.pool.PoolProperties;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.DefaultResourceLoader;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
/**
* 单例数据源配置
* @author Liuyuhang
*
*/
@Configuration
public class DataConfig { private static final String url = "jdbc:mysql://xxx.xxx.xxx.xxx:3306/dataBaseName?cuseUnicode=true&characterEncoding=utf-8&useSSL=false";
private static final String driver = "com.mysql.jdbc.Driver";
private static final String username = "root";
private static final String password = "root"; /**
* SqlSessionFactory
*/
private SqlSessionFactory sqlSessionFactory = null; /**
* 单例的类对象
*/
private static volatile DataConfig dataConfig; /**
* 无参构造
* @throws Exception
*/
public DataConfig() throws Exception {
setSqlSessionFactory();
System.out.println("DataConfig init");
} /**
* 双验证单例模式
* @return
* @throws Exception
*/
public static DataConfig getInstence() throws Exception{
if(null==dataConfig){
synchronized (DataConfig.class) {
if(null==dataConfig){
dataConfig = new DataConfig(); }
}
}
return dataConfig;
} /**
* tomcat pool配置
* @param url
* @param dirver
* @param username
* @param password
* @return
*/
public DataSource dataSource(String url, String dirver, String username, String password) {
PoolProperties p = new PoolProperties();
p.setUrl(url);
p.setDriverClassName(dirver);
p.setUsername(username);
p.setPassword(password);
p.setTestWhileIdle(false);
p.setTestOnBorrow(true);
p.setValidationQuery("SELECT 1");
p.setTestOnReturn(false);
p.setValidationInterval(30000);
p.setTimeBetweenEvictionRunsMillis(30000);
p.setMaxActive(100);
p.setInitialSize(10);
p.setMaxWait(10000);
p.setRemoveAbandonedTimeout(60);
p.setMinEvictableIdleTimeMillis(30000);
p.setMinIdle(10);
p.setLogAbandoned(true);
p.setRemoveAbandoned(true);
DataSource datasource = new DataSource();
datasource.setPoolProperties(p);
return datasource;
} /**
* setSqlSessionFactory,构造的时候运行一次,可实例化以后也可手动调用修改SqlSessionFactory
* @throws Exception
*/
public void setSqlSessionFactory() throws Exception {
DataSource dataSource = dataSource(url, driver, username, password);
// 创建sessionFactory
SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
factoryBean.setDataSource(dataSource);// 加载数据源
// 扫描mapper.xml
Resource[] resources = new PathMatchingResourcePatternResolver().getResources("classpath:com/FM/mapper/*.xml");
factoryBean.setMapperLocations(resources);
// 读取config
factoryBean.setConfigLocation(new DefaultResourceLoader().getResource("classpath:mybatis-config.xml"));
this.sqlSessionFactory = factoryBean.getObject();
System.out.println("setSqlSessionFactory init");
} /**
* 获取SqlSessionFactory
* @return
* @throws Exception
*/
public SqlSessionFactory getSessionFactory() throws Exception {
if (null == sqlSessionFactory) {
setSqlSessionFactory();
}
return this.sqlSessionFactory;
} }
5.说明
- 在不使用连接池情况下，直接加载数据源时，会导致mysql数据库开启连接数量持续增长到最大值，导致mysql数据库无法使用
6.测试
测试时应观察mysql连接数量增长情况，总数量，对数据库进行多次请求。
以上!