项目案例模板之jdbc两种连接方式

Posted 2022-10-09 zyx110

项目案例模板之jdbc两种连接方式

第一种连接方式

JDBCUtils.java

 package jdbc;
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         import org.junit.jupiter.api.Test;
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         import java.sql.Connection;
         import java.sql.DriverManager;
         import java.sql.SQLException;
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 public class JDBCUtils 
     public static Connection connection;
     private static String url="jdbc:mysql://localhost:3306/aaa?useUnicode=true&characterEncoding=utf-8";
     private static String username="root";
     private static String password="root";
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     static
         try 
             Class.forName("com.mysql.jdbc.Driver");
             connection = DriverManager.getConnection(url,username,password);
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          catch (ClassNotFoundException e) 
             e.printStackTrace();
          catch (SQLException e) 
             e.printStackTrace();
         
     
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     public static Connection getConnection()
         return connection;
     
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     @Test
     public void test()
         Connection connection = JDBCUtils.getConnection();
         System.out.println(connection);
     
 

　　

第二种连接方式

db.properties

 url=jdbc:mysql://localhost:3306/aaa?useUnicode=true&characterEncoding=utf-8
 username=root
 password=root

JDBCUtils2.java

package jdbc;
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 import org.junit.jupiter.api.Test;
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 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
 import java.util.Properties;
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 public class JDBCUtils2 
     private static Connection connection;
     private static String url;
     private static String username;
     private static String password;
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     static 
         try 
             //动态加载驱动
             Class.forName("com.mysql.jdbc.Driver");
             //加载配置文件
             Properties properties = new Properties();
             properties.load(new FileInputStream("src/main/java/db.properties"));
             url = properties.getProperty("url");
             username = properties.getProperty("username");
             password = properties.getProperty("password");
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             connection = DriverManager.getConnection(url,username,password);
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          catch (ClassNotFoundException e) 
             e.printStackTrace();
          catch (FileNotFoundException e) 
             e.printStackTrace();
          catch (IOException e) 
             e.printStackTrace();
          catch (SQLException e) 
             e.printStackTrace();
         
     
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     public static Connection getConnection()
         return connection;
     
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     @Test
     public void test()
         Connection connection = JDBCUtils2.getConnection();
         System.out.println(connection);