1. Java-数据库连接池基本使用
Maven配置:
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.22</version>
</dependency>
2. Java代码示例如下:
package DruidDemo;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import pojo.Account;
import javax.sql.DataSource;
import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
/**
* @author Jensen
* {@data 2022/12/25}
*/
public class DruidTest {
public static void druidTest() throws Exception {
//1.导入jar包
//2.定义配置文件
//3. 加载配置文件
Properties props = new Properties();
props.load(new FileInputStream("src/main/java/druid.properties"));
//4. 获取连接池对象
DataSource dataSource = DruidDataSourceFactory.createDataSource(props);
//5. 获取数据库连接
Connection con = dataSource.getConnection();
//6. 创建声明;
Statement stmt = con.createStatement();
//7. 查询语句实战;
ResultSet rs = stmt.executeQuery("select * from tb_user");
//8 创建List集合
List<Account> accounts = new ArrayList<>();
//8.1 循环输出;
while (rs.next()) {
//1.0 实例化List中的Account类中的方法;
Account account = new Account();
/**这里也可以通过输入数字去定义列名,比如username也可以通过2进行定义*/
int id = rs.getInt(1);
String username = rs.getString("username");
String pass = rs.getString("password");
//1.1 依次将查询出来的数据遍历添加到Account类中
account.setId(id);
account.setUser(username);
account.setPass(pass);
//1.2 将存储在Account类中的用户数据加载到List集合中
accounts.add(account);
}
// 1.3输出集合中的内容数据
for (Account account : accounts) {
System.out.println(account);
}
//7. 资源释放;
con.close();
}
public static void main(String[] args) throws Exception{
druidTest();
}
}