浅析JDBC

public static void add(People people){
        //1、获得和数据库的连接
        connection = DBconnection.getcConnection();
        //2、准备SQL语句
        String sql = "insert into people(pname,psex)values(?,?)";
        //3、准备状态，获得执行SQL的命令
        try {
            pStatement = connection.prepareStatement(sql);
            //4、给问号赋值
            pStatement.setString(1, people.getPname());
            pStatement.setString(2, people.getPsex());
            
            int i = pStatement.executeUpdate();
            if (i>0) {
                System.out.println("添加成功");
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            DBconnection.close(connection, pStatement, null);
        }
    }

public static void delete(int pid){
        connection = DBconnection.getcConnection();
        String sqlString = "delete from people where pid=?";
        try {
            pStatement = connection.prepareStatement(sqlString);
            pStatement.setInt(1, pid);
            
            int j = pStatement.executeUpdate();
            if (j>0) {
                System.out.println("删除成功");
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            DBconnection.close(connection, pStatement, null);
        }    
    }

public static void update(String pname,String psex,int pid){
        connection=DBconnection.getcConnection();
        String sql = "update people set pname=?,psex=? where pid = ?";
        
        try {
            pStatement = connection.prepareStatement(sql);
            pStatement.setString(1, pname);
            pStatement.setString(2, psex);
            pStatement.setInt(3, pid);
                
            int y = pStatement.executeUpdate();
            
            if (y>0) {
                System.out.println("更新成功");
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            DBconnection.close(connection, pStatement, null);
        }
        
    }

//根据pid查询
    public static People findByID(int pid){
        People people = null;
        connection = DBconnection.getcConnection();
        
        String sql = "select * from people where pid = ?";
        try {
            pStatement = connection.prepareStatement(sql);
            pStatement.setInt(1, pid);
            //执行
            rSet = pStatement.executeQuery();
            //对结果集进行遍历
            while (rSet.next()) {
                int id = rSet.getInt("pid");
                String name = rSet.getString("pname");
                String sex = rSet.getString("psex");
                //生成ID查询对象
                people = new People(id, name, sex);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            DBconnection.close(connection, pStatement, rSet);
        }
        return people;
    }
    //查询表中所以内容
    public static List<People> findAll(){
        People people = null;
        List<People> list = new ArrayList<People>();
        
        connection = DBconnection.getcConnection();
        
        String sql = "select * form people";
        
        try {
            pStatement = connection.prepareStatement(sql);
            rSet = pStatement.executeQuery();
            
            while(rSet.next()){
                int id = rSet.getInt("pid");
                String name = rSet.getString("pname");
                String sex = rSet.getString("psex");
                //生成ID查询对象
                people = new People(id, name, sex);
                list.add(people);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            DBconnection.close(connection, pStatement, rSet);
        }
        return list;
    }