最原始的连接方式

    2. package com.daijunyi;
    4. import org.junit.Test;
    6. import java.io.InputStream;
    7. import java.sql.Connection;
    8. import java.sql.Driver;
    9. import java.sql.DriverManager;
    10. import java.sql.SQLException;
    11. import java.util.Properties;
    13. public class ConnectionTest {
    15. //    方式一
    16.     @Test
    17.     public void connection() throws SQLException {
    18.         Driver driver = new com.mysql.cj.jdbc.Driver();
    19.         Properties properties = new Properties();
    20.         properties.put("user","root");
    21.         properties.put("password","qwerasdf123");
    22.         String url = "jdbc:mysql://localhost:3306/learn?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&serverTimezone=GMT%2b8";
    23.         Connection connect = driver.connect(url, properties);
    24.         System.out.println(connect);
    25.     }
    27. //    方式三
    28.     @Test
    29.     public void connection1() throws Exception {
    30.         Class<?> aClass = Class.forName("com.mysql.cj.jdbc.Driver");
    31.         Driver driver = (Driver) aClass.newInstance();
    32.         Properties properties = new Properties();
    33.         properties.put("user","root");
    34.         properties.put("password","qwerasdf123");
    35.         String url = "jdbc:mysql://localhost:3306/learn?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&serverTimezone=GMT%2b8";
    36.         Connection connect = driver.connect(url, properties);
    37.         System.out.println(connect);
    38.     }
    40. //    方式三
    41.     @Test
    42.     public void connection2() throws Exception{
    43.         Class<?> aClass = Class.forName("com.mysql.cj.jdbc.Driver");
    44.         Driver driver = (Driver) aClass.newInstance();
    45.         DriverManager.registerDriver(driver);
    46.         Properties properties = new Properties();
    47.         properties.put("user","root");
    48.         properties.put("password","qwerasdf123");
    49.         String url = "jdbc:mysql://localhost:3306/learn?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&serverTimezone=GMT%2b8";
    50.         Connection connection = DriverManager.getConnection(url, properties);
    52.         System.out.println(connection);
    53.     }
    55.     //    方式四 我们只需要加载驱动到内存 ，因为驱动一加载类的时候 静态代码块会自动注册驱动
    56. //     */
    57. //    public class Driver extends NonRegisteringDriver implements java.sql.Driver {
    58. //        //
    59. //        // Register ourselves with the DriverManager
    60. //        //
    61. //        static {
    62. //            try {
    63. //                java.sql.DriverManager.registerDriver(new com.mysql.cj.jdbc.Driver());
    64. //            } catch (SQLException E) {
    65. //                throw new RuntimeException("Can't register driver!");
    66. //            }
    67. //        }
    69.     @Test
    70.     public void connection3() throws Exception{
    71.         Class.forName("com.mysql.cj.jdbc.Driver");
    72. //        Driver driver = (Driver) aClass.newInstance();
    73. //        DriverManager.registerDriver(driver);
    74.         Properties properties = new Properties();
    75.         properties.put("user","root");
    76.         properties.put("password","qwerasdf123");
    77.         String url = "jdbc:mysql://localhost:3306/learn?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&serverTimezone=GMT%2b8";
    78.         Connection connection = DriverManager.getConnection(url, properties);
    80.         System.out.println(connection);
    81.     }
    83.     @Test
    84.     public void connection4() throws Exception{
    86.         InputStream resourceAsStream = ConnectionTest.class.getClassLoader().getResourceAsStream("jdbc.properties");
    87.         Properties properties = new Properties();
    88.         properties.load(resourceAsStream);
    90.         String driver = properties.getProperty("driver");
    91.         String url = properties.getProperty("url");
    92.         String user = properties.getProperty("user");
    93.         String password = properties.getProperty("password");
    95.         Class.forName(driver);
    96.         Connection connection = DriverManager.getConnection(url, user, password);
    97.         System.out.println(connection);
    98.     }
    99. }
    1. url=jdbc:mysql://localhost:3306/learn?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&serverTimezone=GMT%2b8
    2. user=root
    3. password=qwerasdf123
    4. driver=com.mysql.cj.jdbc.Driver

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