DBCP连接池操作mysql数据库

1 导入jar包：commons-dbcp-1.4.jar， commons-pool-1.5.6.jar，mysql-connector-java-5.1.37-bin.jar

2 导入配置文件：dbcpconfig.properties

3 编写工具类DBCPUtils

public class DBCPUtils {
    private static DataSource ds;
    static{
        try {
            Properties ps = new Properties();
            ps.load(new FileInputStream("dbcpconfig.properties"));
            ds = BasicDataSourceFactory.createDataSource(ps);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } 
    }
    
    public static Connection getConnection() {
        try {
            return ds.getConnection();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            throw new RuntimeException();
        }
    }
    public static void closeAll(Connection conn, PreparedStatement pst, ResultSet rs) {
        if(rs != null){
            try {
                rs.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
        if(pst != null){
            try {
                pst.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
        if(conn != null){
            try {
                conn.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

4 使用工具类操作mysq

public class DBCPUtilsDemo {
    public static void main(String[] args) throws SQLException {
        insert();
        query();
    }

    public static void insert() throws SQLException {
            Connection conn = DBCPUtils.getConnection();
            String sql = "insert into practice (cid, cname) values (?, ?)";
            PreparedStatement pst = conn.prepareStatement(sql);
            pst.setObject(1, 1);
            pst.setObject(2, "abc123");
            int rows = pst.executeUpdate();
            System.out.println(rows);
            DBCPUtils.closeAll(conn, pst, null);
    }
    
    public static void query() throws SQLException{
        Connection conn = DBCPUtils.getConnection();
        Statement st = conn.createStatement();
        String sql = "select * from users";
        ResultSet rs = st.executeQuery(sql);
        while(rs.next()){
            System.out.println(rs.getObject("uid") + "\t" + rs.getObject("username") + "\t" + rs.getObject("password") + "\t");
        }
    }
}