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<Brand> 封装Brand对象，装载List集合
   Brand brand = null;
   List<Brand> 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();
  

  }
  }