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
1 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 2 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 3 <modelVersion>4.0.0</modelVersion> 4 <groupId>Tit</groupId> 5 <artifactId>FM</artifactId> 6 <version>0.0.1-SNAPSHOT</version> 7 <packaging>war</packaging> 8 9 <parent> 10 <groupId>org.springframework.boot</groupId> 11 <artifactId>spring-boot-starter-parent</artifactId> 12 <version>1.5.3.RELEASE</version> 13 <relativePath /> <!-- lookup parent from repository --> 14 </parent> 15 <dependencies> 16 17 <!-- spring boot web --> 18 <dependency> 19 <groupId>org.springframework.boot</groupId> 20 <artifactId>spring-boot-starter-web</artifactId> 21 </dependency> 22 23 <dependency> 24 <groupId>junit</groupId> 25 <artifactId>junit</artifactId> 26 <version>3.8.1</version> 27 <scope>test</scope> 28 </dependency> 29 30 <dependency> 31 <groupId>org.apache.tomcat.embed</groupId> 32 <artifactId>tomcat-embed-logging-juli</artifactId> 33 <version>7.0.62</version> 34 </dependency> 35 36 <!-- 添加MySQL依赖 --> 37 <dependency> 38 <groupId>mysql</groupId> 39 <artifactId>mysql-connector-java</artifactId> 40 </dependency> 41 <!-- 添加JDBC依赖 --> 42 <dependency> 43 <groupId>org.springframework.boot</groupId> 44 <artifactId>spring-boot-starter-jdbc</artifactId> 45 </dependency> 46 <!-- mybaits基础依赖 --> 47 <dependency> 48 <groupId>org.mybatis</groupId> 49 <artifactId>mybatis</artifactId> 50 <version>3.4.0</version> 51 </dependency> 52 <!-- mybatis插件依赖 --> 53 <dependency> 54 <groupId>org.mybatis.spring.boot</groupId> 55 <artifactId>mybatis-spring-boot-starter</artifactId> 56 <version>1.1.1</version> 57 </dependency> 58 <!-- mapper依赖 --> 59 <dependency> 60 <groupId>tk.mybatis</groupId> 61 <artifactId>mapper</artifactId> 62 <version>3.3.7</version> 63 </dependency> 64 65 66 <dependency> 67 <groupId>org.springframework.boot</groupId> 68 <artifactId>spring-boot-configuration-processor</artifactId> 69 <optional>true</optional> 70 </dependency> 71 72 <!-- 热部署 --> 73 <dependency> 74 <groupId>org.springframework.boot</groupId> 75 <artifactId>spring-boot-devtools</artifactId> 76 <optional>true</optional> 77 <scope>true</scope> 78 </dependency> 79 <!-- end of 热部署 --> 80 </dependencies> 81 82 <properties> 83 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 84 <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> 85 <java.version>1.7</java.version> 86 87 <webVersion>3.0</webVersion> 88 </properties> 89 <build> 90 <finalName>FM</finalName> 91 <plugins> 92 <plugin> 93 <groupId>org.springframework.boot</groupId> 94 <artifactId>spring-boot-maven-plugin </artifactId> 95 </plugin> 122 </plugins> 143 144 </build> 145 </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：
1 package com.FM.config; 2 3 import org.apache.ibatis.session.SqlSessionFactory; 4 import org.apache.tomcat.jdbc.pool.DataSource; 5 import org.apache.tomcat.jdbc.pool.PoolProperties; 6 import org.mybatis.spring.SqlSessionFactoryBean; 7 import org.springframework.context.annotation.Configuration; 8 import org.springframework.core.io.DefaultResourceLoader; 9 import org.springframework.core.io.Resource; 10 import org.springframework.core.io.support.PathMatchingResourcePatternResolver; 11 /** 12 * 单例数据源配置 13 * @author Liuyuhang 14 * 15 */ 16 @Configuration 17 public class DataConfig { 18 19 private static final String url = "jdbc:mysql://xxx.xxx.xxx.xxx:3306/dataBaseName?cuseUnicode=true&characterEncoding=utf-8&useSSL=false"; 20 private static final String driver = "com.mysql.jdbc.Driver"; 21 private static final String username = "root"; 22 private static final String password = "root"; 23 24 /** 25 * SqlSessionFactory 26 */ 27 private SqlSessionFactory sqlSessionFactory = null; 28 29 /** 30 * 单例的类对象 31 */ 32 private static volatile DataConfig dataConfig; 33 34 /** 35 * 无参构造 36 * @throws Exception 37 */ 38 public DataConfig() throws Exception { 39 setSqlSessionFactory(); 40 System.out.println("DataConfig init"); 41 } 42 43 /** 44 * 双验证单例模式 45 * @return 46 * @throws Exception 47 */ 48 public static DataConfig getInstence() throws Exception{ 49 if(null==dataConfig){ 50 synchronized (DataConfig.class) { 51 if(null==dataConfig){ 52 dataConfig = new DataConfig(); 53 54 } 55 } 56 } 57 return dataConfig; 58 } 59 60 /** 61 * tomcat pool配置 62 * @param url 63 * @param dirver 64 * @param username 65 * @param password 66 * @return 67 */ 68 public DataSource dataSource(String url, String dirver, String username, String password) { 69 PoolProperties p = new PoolProperties(); 70 p.setUrl(url); 71 p.setDriverClassName(dirver); 72 p.setUsername(username); 73 p.setPassword(password); 74 p.setTestWhileIdle(false); 75 p.setTestOnBorrow(true); 76 p.setValidationQuery("SELECT 1"); 77 p.setTestOnReturn(false); 78 p.setValidationInterval(30000); 79 p.setTimeBetweenEvictionRunsMillis(30000); 80 p.setMaxActive(100); 81 p.setInitialSize(10); 82 p.setMaxWait(10000); 83 p.setRemoveAbandonedTimeout(60); 84 p.setMinEvictableIdleTimeMillis(30000); 85 p.setMinIdle(10); 86 p.setLogAbandoned(true); 87 p.setRemoveAbandoned(true); 88 DataSource datasource = new DataSource(); 89 datasource.setPoolProperties(p); 90 return datasource; 91 } 92 93 /** 94 * 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 95 * @throws Exception 96 */ 97 public void setSqlSessionFactory() throws Exception { 98 DataSource dataSource = dataSource(url, driver, username, password); 99 // 创建sessionFactory 100 SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean(); 101 factoryBean.setDataSource(dataSource);// 加载数据源 102 // 扫描mapper.xml 103 Resource[] resources = new PathMatchingResourcePatternResolver().getResources("classpath:com/FM/mapper/*.xml"); 104 factoryBean.setMapperLocations(resources); 105 // 读取config 106 factoryBean.setConfigLocation(new DefaultResourceLoader().getResource("classpath:mybatis-config.xml")); 107 this.sqlSessionFactory = factoryBean.getObject(); 108 System.out.println("setSqlSessionFactory init"); 109 } 110 111 /** 112 * 获取SqlSessionFactory 113 * @return 114 * @throws Exception 115 */ 116 public SqlSessionFactory getSessionFactory() throws Exception { 117 if (null == sqlSessionFactory) { 118 setSqlSessionFactory(); 119 } 120 return this.sqlSessionFactory; 121 } 122 123 }
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!