5.22总结

package com.mf.jdbc.exmaple;

import com.alibaba.druid.pool.DruidDataSourceFactory;
import com.mf.jdbc.Brand;
import org.junit.Test;

import javax.sql.DataSource;
import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;

/**

• 品牌数据的增删改查操作
  */
  public class BrandTest {

  /**

  • 查询所有
  • 1. SQL：select * from tb_brand;
  • 2. 参数：不需要
  • 3. 结果：List
       */

  @Test
  public void testSelectAll() throws Exception {
  //1. 获取Connection
  //3. 加载配置文件
  Properties prop = new Properties();
  prop.load(new FileInputStream("./src/druid.properties"));
  //4. 获取连接池对象
  DataSource dataSource = DruidDataSourceFactory.createDataSource(prop);

  //5. 获取数据库连接 Connection
  Connection conn = dataSource.getConnection();

  //2. 定义SQL
  String sql = "select * from tb_brand;";

  //3. 获取pstmt对象
  PreparedStatement pstmt = conn.prepareStatement(sql);

  //4. 设置参数

  //5. 执行SQL
  ResultSet rs = pstmt.executeQuery();

  //6. 处理结果 List 封装Brand对象，装载List集合
  Brand brand = null;
  List brands = new ArrayList<>();
  while (rs.next()){
  //获取数据
  int id = rs.getInt("id");
  String brandName = rs.getString("brand_name");
  String companyName = rs.getString("company_name");
  int ordered = rs.getInt("ordered");
  String description = rs.getString("description");
  int status = rs.getInt("status");
  //封装Brand对象
  brand = new Brand();
  brand.setId(id);
  brand.setBrandName(brandName);
  brand.setCompanyName(companyName);
  brand.setOrdered(ordered);
  brand.setDescription(description);
  brand.setStatus(status);

  //装载集合
  brands.add(brand);

  }
  System.out.println(brands);
  //7. 释放资源
  rs.close();
  pstmt.close();
  conn.close();

  }

  /**

  • 添加
  • 1. SQL：insert into tb_brand(brand_name, company_name, ordered, description, status) values(?,?,?,?,?);
  • 2. 参数：需要，除了id之外的所有参数信息
  • 3. 结果：boolean
       */

  @Test
  public void testAdd() throws Exception {
  // 接收页面提交的参数
  String brandName = "香飘飘";
  String companyName = "香飘飘";
  int ordered = 1;
  String description = "绕地球一圈";
  int status = 1;

  //1. 获取Connection
  //3. 加载配置文件
  Properties prop = new Properties();
  prop.load(new FileInputStream("./src/druid.properties"));
  //4. 获取连接池对象
  DataSource dataSource = DruidDataSourceFactory.createDataSource(prop);

  //5. 获取数据库连接 Connection
  Connection conn = dataSource.getConnection();

  //2. 定义SQL
  String sql = "insert into tb_brand(brand_name, company_name, ordered, description, status) values(?,?,?,?,?);";

  //3. 获取pstmt对象
  PreparedStatement pstmt = conn.prepareStatement(sql);

  //4. 设置参数
  pstmt.setString(1,brandName);
  pstmt.setString(2,companyName);
  pstmt.setInt(3,ordered);
  pstmt.setString(4,description);
  pstmt.setInt(5,status);

  //5. 执行SQL
  int count = pstmt.executeUpdate(); // 影响的行数
  //6. 处理结果
  System.out.println(count > 0);

  //7. 释放资源
  pstmt.close();
  conn.close();

  }

  /**

  • 修改
  • 1. SQL：

  update tb_brand
  set brand_name = ?,
  company_name= ?,
  ordered = ?,
  description = ?,
  status = ?
  where id = ?

  • 2. 参数：需要，所有数据
  • 3. 结果：boolean
       */

  @Test
  public void testUpdate() throws Exception {
  // 接收页面提交的参数
  String brandName = "香飘飘";
  String companyName = "香飘飘";
  int ordered = 1000;
  String description = "绕地球三圈";
  int status = 1;
  int id = 4;

  //1. 获取Connection
  //3. 加载配置文件
  Properties prop = new Properties();
  prop.load(new FileInputStream("jdbc-demo/src/druid.properties"));
  //4. 获取连接池对象
  DataSource dataSource = DruidDataSourceFactory.createDataSource(prop);

  //5. 获取数据库连接 Connection
  Connection conn = dataSource.getConnection();

  //2. 定义SQL
  String sql = " update tb_brand\n" +
  " set brand_name = ?,\n" +
  " company_name= ?,\n" +
  " ordered = ?,\n" +
  " description = ?,\n" +
  " status = ?\n" +
  " where id = ?";

  //3. 获取pstmt对象
  PreparedStatement pstmt = conn.prepareStatement(sql);

  //4. 设置参数
  pstmt.setString(1,brandName);
  pstmt.setString(2,companyName);
  pstmt.setInt(3,ordered);
  pstmt.setString(4,description);
  pstmt.setInt(5,status);
  pstmt.setInt(6,id);

  //5. 执行SQL
  int count = pstmt.executeUpdate(); // 影响的行数
  //6. 处理结果
  System.out.println(count > 0);

  //7. 释放资源
  pstmt.close();
  conn.close();

  }

  /**

  • 删除
  • 1. SQL：

  delete from tb_brand where id = ?

  • 2. 参数：需要，id
  • 3. 结果：boolean
       */

  @Test
  public void testDeleteById() throws Exception {
  // 接收页面提交的参数

  int id = 4;

  //1. 获取Connection
  //3. 加载配置文件
  Properties prop = new Properties();
  prop.load(new FileInputStream("jdbc-demo/src/druid.properties"));
  //4. 获取连接池对象
  DataSource dataSource = DruidDataSourceFactory.createDataSource(prop);

  //5. 获取数据库连接 Connection
  Connection conn = dataSource.getConnection();

  //2. 定义SQL
  String sql = " delete from tb_brand where id = ?";

  //3. 获取pstmt对象
  PreparedStatement pstmt = conn.prepareStatement(sql);

  //4. 设置参数

  pstmt.setInt(1,id);

  //5. 执行SQL
  int count = pstmt.executeUpdate(); // 影响的行数
  //6. 处理结果
  System.out.println(count > 0);

  //7. 释放资源
  pstmt.close();
  conn.close();

  }
  }