MyBatis-Plus：创建动态数据源

简述工具类注意事项

简述

由于一些业务场景需要，我们可能需要使用MyBatis-Plus动态连接数据库，进行数据交互。

工具类

import com.baomidou.mybatisplus.generator.config.DataSourceConfig; import com.github.pagehelper.PageHelper; import com.github.pagehelper.PageInterceptor; import org.apache.ibatis.datasource.pooled.PooledDataSource; import org.apache.ibatis.mapping.Environment; import org.apache.ibatis.session.Configuration; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import org.apache.ibatis.transaction.TransactionFactory; import org.apache.ibatis.transaction.jdbc.JdbcTransactionFactory; import javax.sql.DataSource; import java.sql.SQLException; import java.util.Properties; public class JdbcSessionFactory { private static JdbcSessionFactory instance = null; private SqlSessionFactory sqlSessionFactory; private DataSourceConfig dataSourceConfig; private JdbcSessionFactory() { } /** * 尝试获取实例 * @return */ public static JdbcSessionFactory tryGetInstance() { if (instance == null) { throw new RuntimeException(); } return instance; } /** * 获取连接实例 * @param jdbcUrl * @param name * @param password * @return */ public static JdbcSessionFactory getInstance(String jdbcUrl, String name, String password) { if (instance == null) { instance = new JdbcSessionFactory(); instance.createJdbcSessionFactory(jdbcUrl, "com.mysql.jdbc.Driver", name, password); } return instance; } /** * 测试数据库连接 * @param jdbcUrl * @param name * @param password * @return */ public static Boolean sqlTest(String jdbcUrl, String name, String password) { return sqlTest(jdbcUrl, "com.mysql.jdbc.Driver", name, password); } /** * 获取一个SqlSession会话 * @return */ public SqlSession getSqlSession() { return this.sqlSessionFactory.openSession(); } public DataSourceConfig getDataSourceConfig() { return this.dataSourceConfig; } /** * 创建jdbcSession工厂 * @param jdbcUrl * @param driver * @param name * @param password * @return */ private Boolean createJdbcSessionFactory(String jdbcUrl, String driver, String name, String password) { if (!sqlTest(jdbcUrl, "com.mysql.jdbc.Driver", name, password)) { throw new RuntimeException("db connect time out"); } // 保存数据库配置 dataSourceConfig = new DataSourceConfig(); dataSourceConfig.setDriverName(driver); dataSourceConfig.setUrl(jdbcUrl); dataSourceConfig.setUsername(name); dataSourceConfig.setPassword(password); DataSource dataSource =new PooledDataSource(driver,jdbcUrl,name,password); TransactionFactory transactionFactory = new JdbcTransactionFactory(); Environment environment = new Environment("development", transactionFactory, dataSource); Configuration configuration = new Configuration(environment); configuration.setDefaultStatementTimeout(8); // 分页 PageInterceptor pageInterceptor = new PageInterceptor(); pageInterceptor.plugin(getPageHelper()); configuration.addInterceptor(pageInterceptor); configuration.addMappers("com.cj.tools.mybatisplus.mapper"); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration); this.sqlSessionFactory = sqlSessionFactory; return true; } /** * 分页插件 * @return */ private PageHelper getPageHelper(){ PageHelper pageHelper=new PageHelper(); Properties properties=new Properties(); properties.setProperty("offsetAsPageNum", "true"); properties.setProperty("rowBoundsWithCount", "true"); properties.setProperty("reasonable", "true"); pageHelper.setProperties(properties); return pageHelper; } /** * 测试数据库连接 * @param jdbcUrl * @param driver * @param name * @param password * @return */ private static Boolean sqlTest(String jdbcUrl, String driver, String name, String password) { DataSource dataSource =new PooledDataSource(driver,jdbcUrl,name,password); try { dataSource.setLoginTimeout(5); dataSource.getConnection().getClientInfo(); } catch (SQLException e) { return false; } return true; } }

注意事项

1）如果进行多次连接，每次连接时注意进行sqlTest，否则可能出现连接不上问题。 2）分页插件如果不需要，可自行删除