数据库复用代码【c3p0配置文件、数据库连接池】

本是古典何须时尚 2021-09-17 05:46 396阅读 0赞

# 前言 #

为了复用，记载一些以前写过的工具类、方法

# c3p0配置文件【c3p0-config.xml】 #

<?xml version="1.0" encoding="UTF-8" ?>
    <c3p0-config>
        <default-config>
            <property name="driverClass">com.mysql.jdbc.Driver</property>
            <property name="jdbcUrl">jdbc:mysql://localhost:3306/zhongfucheng?characterEncoding=utf8</property>
            <property name="user">root</property>
            <property name="password">root</property>
    
            <property name="acquireIncrement">5</property>
            <property name="initialPoolSize">10</property>
            <property name="minPoolSize">5</property>
            <property name="maxPoolSize">20</property>
        </default-config>
    
        <named-config name="mysql">
            <property name="driverClass">com.mysql.jdbc.Driver</property>
            <property name="jdbcUrl">jdbc:mysql://localhost:3306/zhongfucheng</property>
            <property name="user">root</property>
            <property name="password">root</property>
    
            <property name="acquireIncrement">5</property>
            <property name="initialPoolSize">10</property>
            <property name="minPoolSize">5</property>
            <property name="maxPoolSize">20</property>
        </named-config>
    
    
        <named-config name="oracle">
            <property name="driverClass">oracle.jdbc.driver.OracleDriver</property>
            <property name="jdbcUrl">jdbc:oracle:thin:@//localhost:1521/事例名...</property>
            <property name="user">用户名</property>
            <property name="password">密码</property>
    
            <property name="acquireIncrement">5</property>
            <property name="initialPoolSize">10</property>
            <property name="minPoolSize">5</property>
            <property name="maxPoolSize">20</property>
        </named-config>
    </c3p0-config>

# 数据库连接池c3p0 #

import com.mchange.v2.c3p0.ComboPooledDataSource;
    
        import javax.sql.DataSource;
        import java.sql.Connection;
        import java.sql.SQLException;
    
        /** * Created by ozc on 2017/2/22. */
        public class Utils2DB { 
    
            private static ComboPooledDataSource comboPooledDataSource = null;
    
                static {
    
                    //它会自动寻找配置文件，节点为mysql的数据库
                    comboPooledDataSource = new ComboPooledDataSource();
                }
    
    
            public static DataSource getDataSource() {
                return comboPooledDataSource ;
            }
    
            public static Connection connection() {
                try {
                    return comboPooledDataSource.getConnection();
                } catch (SQLException e) {
                    e.printStackTrace();
                    throw new RuntimeException("数据库初始化失败了！");
                }
            }
        }