JDBC 连接sql server Demo

package com.example.democrud.democurd;
import java.sql.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class sqlserver {
    public static void main(String[] args) {
        test1();
     //   test2();
    }
    public static void test1(){
        //默认sql server 驱动类
        String driverName = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
        //此处localhost 为本地的地址  1433 默认端口  demo 为主表 的名字
        String dbURL = "jdbc:sqlserver://localhost:1433;databaseName=demo";
        String userName = "sa";            //sqlserver用户名
        String userPwd = "root";    //sqlserver用户密码
        try {
            Class.forName(driverName);   //加载sqlserver的驱动类
            System.out.println("sqlServer load success!");
        } catch (ClassNotFoundException a) {
            System.out.println("sqlServer load failed!");
            a.printStackTrace();
        }
        Connection dbcon = null;
        try {
            //处理与数据库的连接
            dbcon = DriverManager.getConnection(dbURL, userName, userPwd);
            Statement stmt = dbcon.createStatement();
            String sql = "select * from Demo";
            //ResultSet对象，其包含给定查询生成的数据
            ResultSet resultSet = stmt.executeQuery(sql);
            //获取执行的SQL语句的元数据
            ResultSetMetaData metaData = resultSet.getMetaData();
            //获取执行的SQL语句查询的列的个数
            int columnCount = metaData.getColumnCount();
            //获取表中的所有数据，字段 + 值
            List<Map<String, Object>> list1 = new ArrayList<>();
            List<Map<String, Object>> list2 = new ArrayList<>();
            List<Object> list3 = new ArrayList<>();
            //取出ResultSet中表的记录。如果可以取出则返回true,否则返回false
            while (resultSet.next()) {
                //数据
                Map<String, Object> row = new HashMap<>();
                //表结构--包含字段类型
                Map<String, Object> map = new HashMap<>();
                for (int i = 0; i < columnCount; i++) {
                    //字段
                    String columnLabel = metaData.getColumnLabel(i + 1);
                    //字段类型
                    String columnTypeName = metaData.getColumnTypeName(i + 1);
                    //值
                    Object value = resultSet.getObject(i + 1);
                    row.put(columnLabel, value);
                    map.put(columnLabel, columnTypeName);
                    list3.add(value);
                }
                list1.add(row);
                list2.add(map);
                System.out.println("获取到的key的值"+list2);
                System.out.println("获取到的value的值"+list1);
                System.out.println("单独获取V的值"+list3);
            }
            System.out.println("sqlServer connect success! sql server 连接成功");
            dbcon.close();
        } catch (SQLException e) {
            System.out.println("sqlServer connect failed!");
            e.printStackTrace();
        }
    }
    public static void test2(){
        String driverName = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
        String dbURL = "jdbc:sqlserver://120.27.229.213:65023;databaseName=davinci3";
        String userName = "sa";            //sqlserver用户名
        String userPwd = "BSa!67365021";    //sqlserver用户密码
        try {
            Class.forName(driverName);   //加载sqlserver的驱动类
            System.out.println("sqlServer load success!");
        } catch (ClassNotFoundException a) {
            System.out.println("sqlServer load failed!");
            a.printStackTrace();
        }
        Connection dbcon = null;
        try {
            //处理与数据库的连接
            dbcon = DriverManager.getConnection(dbURL, userName, userPwd);
            Statement stmt = dbcon.createStatement();
            String sql = "select * from display";
            //ResultSet对象，其包含给定查询生成的数据
            ResultSet resultSet = stmt.executeQuery(sql);
            //获取执行的SQL语句的元数据
            ResultSetMetaData metaData = resultSet.getMetaData();
            //获取执行的SQL语句查询的列的个数
            int columnCount = metaData.getColumnCount();
            //获取表中的所有数据，字段 + 值
            List<Map<String, Object>> list1 = new ArrayList<>();
            List<Map<String, Object>> list2 = new ArrayList<>();
            //取出ResultSet中表的记录。如果可以取出则返回true,否则返回false
            while (resultSet.next()) {
                //数据
                Map<String, Object> row = new HashMap<>();
                //表结构--包含字段类型
                Map<String, Object> map = new HashMap<>();
                for (int i = 0; i < columnCount; i++) {
                    //字段
                    String columnLabel = metaData.getColumnLabel(i + 1);
                    //字段类型
                    String columnTypeName = metaData.getColumnTypeName(i + 1);
                    //值
                    Object value = resultSet.getObject(i + 1);
                    row.put(columnLabel, value);
                    map.put(columnLabel, columnTypeName);
                }
                list1.add(row);
                list2.add(map);
                System.out.println(list1);
                System.out.println(list2);
            }
            System.out.println("sqlServer connect success!");
            dbcon.close();
        } catch (SQLException e) {
            System.out.println("sqlServer connect failed!");
            e.printStackTrace();
        }
    }
}