C3P0工具类的封装

电玩女神 2022-04-05 04:20 246阅读 0赞

使用C3P0连接池所需要的jar包：  
c3p0-0.9.1.2.jar  
commons-dbcp-1.4.jar  
commons-dbutils-1.4.jar  
commons-pool-1.5.6.jar  
mysql-connector-java-5.1.39-bin.jar  
ojdbc6.jar

utils代码：

package util;
    
    import java.sql.Connection;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    import javax.sql.DataSource;
    
    import com.mchange.v2.c3p0.ComboPooledDataSource;
    
    public class DataSourceUtils {
    
    	private static DataSource dataSource = new ComboPooledDataSource("mysql");
    
    	private static ThreadLocal<Connection> tl = new ThreadLocal<Connection>();
    
    	// 直接可以获取一个连接池
    	public static DataSource getDataSource() {
    		return dataSource;
    	}
    	
    	public static Connection getConnection() throws SQLException{
    		return dataSource.getConnection();
    	}
    
    	// 获取连接对象
    	public static Connection getCurrentConnection() throws SQLException {
    
    		Connection con = tl.get();
    		if (con == null) {
    			con = dataSource.getConnection();
    			tl.set(con);
    		}
    		return con;
    	}
    
    	// 开启事务
    	public static void startTransaction() throws SQLException {
    		Connection con = getCurrentConnection();
    		if (con != null) {
    			con.setAutoCommit(false);
    		}
    	}
    
    	// 事务回滚
    	public static void rollback() throws SQLException {
    		Connection con = getCurrentConnection();
    		if (con != null) {
    			con.rollback();
    		}
    	}
    
    	// 提交并且 关闭资源及从ThreadLocall中释放
    	public static void commitAndRelease() throws SQLException {
    		Connection con = getCurrentConnection();
    		if (con != null) {
    			con.commit(); // 事务提交
    			con.close();// 关闭资源
    			tl.remove();// 从线程绑定中移除
    		}
    	}
    	// 关闭资源方法
    	public static void closeConnection() throws SQLException {
    		Connection con = getCurrentConnection();
    		if (con != null) {
    			con.close();
    		}
    	}
    	public static void closeStatement(Statement st) throws SQLException {
    		if (st != null) {
    			st.close();
    		}
    	}
    	public static void closeResultSet(ResultSet rs) throws SQLException {
    		if (rs != null) {
    			rs.close();
    		}
    	}
    }

书写c3p0-config.xml文件

<?xml version="1.0" encoding="UTF-8"?>
    <c3p0-config>
    	<default-config>
    		<property name="driverClass">com.mysql.jdbc.Driver</property>
    		<property name="jdbcUrl">jdbc:mysql://127.0.0.1:3306/learnj2ee?useSSL=false</property>
    		<property name="user">root</property>
    		<property name="password">123456</property>
    		<property name="initialPoolSize">5</property>
    		<property name="maxPoolSize">20</property>
    	</default-config>
    
    	<named-config name="oracle">
    		<property name="driverClass">oracle.jdbc.OracleDriver</property>
    		<property name="jdbcUrl">jdbc:oracle:thin:@10.10.130.115:1521:tgood</property>
    		<property name="user">infodba</property>
    		<property name="password">infodba</property>
    	</named-config>
    	
    	<named-config name="mysql">
    		<property name="driverClass">com.mysql.jdbc.Driver</property>
    		<property name="jdbcUrl">jdbc:mysql://127.0.0.1:3306/shop?useSSL=false</property>
    		<property name="user">root</property>
    		<property name="password">123456</property>
    		<property name="initialPoolSize">5</property>
    		<property name="maxPoolSize">20</property>
    	</named-config>
    </c3p0-config>