JDBC 连接Oracle

首先要导入驱动包，可以网上下对应数据库版本的驱动包，也可以使用自带的，

我就使用自带的，我的目录：C:\Oracle11g\product\11.2.0\dbhome_1\jdbc\lib\ojdbc6.jar。

为了代码逻辑好看，都把异常抛出去，

连接：原始方法

public class BaseDao {
    //定义数据库连接属性
    private static String user = "scott";
    private static String password = "123456";
    private static String driver = "oracle.jdbc.OracleDriver";
    private static String url = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";

    //Oracle 数据库的连接
    public static Connection getOracelConnection() throws ClassNotFoundException, SQLException {
        //利用反射机制加载驱动
        Class.forName(driver);
        Connection conn = null;
        conn = DriverManager.getConnection(url, user, password);
        return conn;
    }
}

读取外部文件，获取 user 、password、url （框架原理）

public class BaseDao1 {
    //定义数据库连接属性
    private static String user;
    private static String password;
    private static String driver;
    private static String url;

    //使用静态代码块，完成连接参数的初始化
    static{
        Properties properties = new Properties();
        //利用反射原理机制加载属性文件、database.properties
        InputStream inputStream = 
             BaseDao1.class.getResourceAsStream("database.properties");
        try {
            //加载物理文件
            properties.load(inputStream);
            user = properties.getProperty("user");
            password = properties.getProperty("password");
            driver = properties.getProperty("driver");
            url = properties.getProperty("url");
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    //Oracle 数据库的连接
    public static Connection getOracelConnection() throws ClassNotFoundException, SQLException {
        //利用反射机制加载驱动
        Class.forName(driver);
        Connection conn = null;
        conn = DriverManager.getConnection(url, user, password);
        return conn;
    }
}

配置文件 database.properties ：

# oracle数据库连接参数
user=scott
password=123456
driver=oracle.jdbc.OracleDriver
url=jdbc:oracle:thin:@127.0.0.1:1521:orcl

两种基本调用：使用存储过程。

public class test2 {
    public static void main(String[] args) throws SQLException, ClassNotFoundException {
        Connection conn = (Connection) BaseDao.getOracelConnection();
        String sql = "call pro_emp(?,?,?,?)";
        CallableStatement callableStatement = conn.prepareCall(sql);
        //设置输入参数的值
        callableStatement.setInt(1, 7788);
        //设置java属性与oracle数据库属性类型的映射关系
        callableStatement.registerOutParameter(2, oracle.jdbc.OracleTypes.VARCHAR);
        callableStatement.registerOutParameter(3,oracle.jdbc.OracleTypes.DOUBLE);
        callableStatement.registerOutParameter(4,oracle.jdbc.OracleTypes.DATE);
        //执行
        callableStatement.execute();
        //取值
        String ename = callableStatement.getString(2);
        Double sal = callableStatement.getDouble(3);
        Date hiredate = callableStatement.getDate(4);
        //输出
        System.out.println("名字："+ename);
        System.out.println("工资："+sal);
        System.out.println("入职日期："+hiredate);
    }
}

public class test3 {
    public static void main(String[] args) throws SQLException, ClassNotFoundException {
        Connection conn = (Connection) BaseDao.getOracelConnection();
        //占位符，（填充符）
        String sql = "call pro_deptno(?,?)";
        CallableStatement callableStatement = conn.prepareCall(sql);
        //设置输入参数的值
        callableStatement.setInt(1, 30);
        //设置java属性与oracle数据库属性类型的映射关系
        callableStatement.registerOutParameter(2, oracle.jdbc.OracleTypes.CURSOR);
        //执行
        callableStatement.execute();
        //取值
        ResultSet rs = (ResultSet) callableStatement.getObject(2);
        while (rs.next()) {
            System.out.println("empno = " + rs.getInt("empno"));
            System.out.println("ename = " + rs.getString("ename"));
            System.out.println("-----------------------------------");
        }
    }
}

表对应类：

public class Test_oracle {
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        conn = BaseDao.getOracelConnection();
        if (conn != null) {
            System.out.println("oracle数据库连接成功");
        }else {
            System.out.println("oracle数据库连接失败");
        }

        PreparedStatement pre = conn.prepareStatement
                ("select * from emp where empno = ?");
        pre.setInt(1,7788);
        ResultSet rs = pre.executeQuery();

        emp emp = new emp();   //一个emp 类
        while (rs.next()) {
            emp.setEmpno(rs.getInt("empno"));
            emp.setEname(rs.getString("ename"));
            emp.setMgr(rs.getInt("mgr"));
            emp.setHiredate(rs.getString("hiredate"));
            emp.setSal(rs.getDouble("sal"));
            emp.setComm(rs.getDouble("comm"));
            emp.setDeptno(rs.getInt("deptno"));
        }
        System.out.println(emp);
    }
}