在上一篇文章C3P0-基于mysql8创立C3P0连接池(jdbcUrl写法)中, 咱们编写好了C3P0的配置文件, 并且自定义工具类C3P0Utils.

当初就通过调用该工具类中的办法的形式执行sql语句,以此测试该工具类可否失常应用(配置文件是否编写正确, 成员办法是否创立胜利 等)

这里应用的数据表是

/** *   我的项目形容: 应用自定义编写的数据库C3P0连接池的工具类获取连贯进行sql查问操作 *   作   者: chain.xx.wdm */ public class C3P0PoolTest {    public static void main(String[] args) {        Connection connection = null;        PreparedStatement preparedStatement = null;        ResultSet resultSet = null;        try {            // 1。获取连贯            connection = C3P0Utils.getConnection();            // 2。创立有占位符模式的sql查问语句            String sql = "select * from employee where name = ?";            // 3。创立prepareStatement对象,并设置占位符的数值            preparedStatement = connection.prepareStatement(sql);            preparedStatement.setString(1,"猪八戒");            // 4。执行sql语句            resultSet = preparedStatement.executeQuery();            // 5。处理结果集            while(resultSet.next()){                int id = resultSet.getInt("id");                String name = resultSet.getString("name");                String gender = resultSet.getString("gender");                double salary = resultSet.getDouble("salary");                String join_date = resultSet.getString("join_date");                System.out.println("id: " + id + ", name: " + name  + ", gender: " + gender + ", salary: " + salary + ", join_date:" + join_date);            }        } catch (SQLException throwables) {            throwables.printStackTrace();        } finally {            // 6。敞开对象            try {                C3P0Utils.close(connection, preparedStatement, resultSet);            } catch (SQLException throwables) {                throwables.printStackTrace();            }        }    }}

运行返回后果正确