JDBC增删改查

/**

• 对开发需求的直观映射是SQL语句.

• 开发步骤:

• 业务需求分析

• 数据库设计

• sql语句设计

• 数据库操作功能类实现

• 业务逻辑代码实现

• 联合测试

• 上线测试

• 维护

• 对于增加删除和修改除了Sql语句的声明不一致以外,其他声明基本一致.

• 封装的思想:

• 相同的保留,不同的传参.

• 使用Statement对象完成增加删除修改

• @author MyPC
  **/
  import java.sql.Connection;
  import java.sql.DriverManager;
  import java.sql.ResultSet;
  import java.sql.SQLException;
  import java.sql.Statement;
  import java.util.ArrayList;
  import com.bjsxt.pojo.Student;
  public class StudentDaoImpl2 {

//增加

	public int insStu(String sname,int sage,double money) throws ClassNotFoundException, SQLException{
		//加载驱动
		Class.forName("oracle.jdbc.driver.OracleDriver");
		//创建连接对象
		Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott", "oracle");
		//创建sql命令对象
		Statement stmt=conn.createStatement();
		//创建sql命令
		String sql="insert into student values(stu_seq.nextval,'"+sname+"','"+sage+"','"+money+"')";
		//执行sql命令
		int i=stmt.executeUpdate(sql);
		//关闭资源
		stmt.close();
		conn.close();
		return i;
	}

//删除

	public int delStu(int snum) throws ClassNotFoundException, SQLException{
		//加载驱动
		Class.forName("oracle.jdbc.driver.OracleDriver");
		//获取连接对象
		Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott", "oracle");
		//获取sql命令对象
		Statement stmt=conn.createStatement();
		//创建sql命令
		String sql="delete from student where snum="+snum;
		//执行sql命令
		int i=stmt.executeUpdate(sql);
		//关闭资源
		stmt.close();
		conn.close();
		return i;
	}

//修改

	public int upStu(int snum,String newName) throws ClassNotFoundException, SQLException{
		//加载驱动
		Class.forName("oracle.jdbc.driver.OracleDriver");
		//获取连接对象
		Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott", "oracle");
		//获取sql命令对象
		Statement stmt=conn.createStatement();
		//创建sql命令
		String sql="update student set sname='"+newName+"' where snum="+snum;
		//执行sql命令
		int i=stmt.executeUpdate(sql);
		//关闭资源
		stmt.close();
		conn.close();
		return i;	
	}

//查询

	public ArrayList<Student> getStudentInfo() throws ClassNotFoundException, SQLException{
		//声明集合对象
		ArrayList<Student> ls=new ArrayList<>();
		//加载驱动
		Class.forName("oracle.jdbc.driver.OracleDriver");
		//获取连接对象
		Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott", "oracle");
		//获取sql命令对象
		Statement stmt=conn.createStatement();
		//创建sql命令
		String sql="select * from student";
		//执行sql命令
		ResultSet rs=stmt.executeQuery(sql);
		//遍历结果
		while(rs.next()){
			Student s=new Student();
			s.setSnum(rs.getInt("snum"));
			s.setSname(rs.getString("sname"));
			s.setSage(rs.getInt("sage"));
			s.setMoney(rs.getDouble("money"));
			ls.add(s);
		}
		//关闭资源
		rs.close();
		stmt.close();
		conn.close();
		return ls;
	}

}