JDBCUtils.java
package jdbc; import org.junit.jupiter.api.Test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; 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"; static{ try { Class.forName("com.mysql.jdbc.Driver"); connection = DriverManager.getConnection(url,username,password); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } } public static Connection getConnection(){ return connection; } @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; import org.junit.jupiter.api.Test; 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; public class JDBCUtils2 { private static Connection connection; private static String url; private static String username; private static String password; 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"); connection = DriverManager.getConnection(url,username,password); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } } public static Connection getConnection(){ return connection; } @Test public void test(){ Connection connection = JDBCUtils2.getConnection(); System.out.println(connection); } }