DataSourceUtils数据库jdbc,用c3p0连接池获取con对象，对事务的操作将con绑定到Threadlocal

package com.utils;

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();

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();
    }
}

}