jdbc在哪里配置加jc，用虚拟机配置jdbc链接MySQL一直连不上

不知道哪里可以找到jdbc的配置文件，在如下提示的地方加上jc

以下内容部分参考ChatGPT模型：

jdbc的配置文件通常是指jdbc.properties文件，它可以在classpath下任意位置，也可以通过System.setProperty方法来设置。如果需要在jdbc链接MySQL时加上jc参数，可以在jdbc连接字符串中加上参数，例如：

jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&jc=true

其中jc=true表示开启jdbc的跟踪功能。如果你的虚拟机配置正确，但是仍然连不上MySQL，可以考虑以下几点：

1. 检查MySQL服务是否已经启动，以及端口号是否正确。
2. 检查jdbc连接字符串是否正确。
3. 检查MySQL的账号和密码是否正确。
4. 检查MySQL的防火墙设置，是否允许来自虚拟机的IP地址访问MySQL服务。

如果我的建议对您有帮助、请点击采纳、祝您生活愉快

用MySQL8的驱动包。

如果你使用的是 Maven 或 Gradle 等构建工具，你可以在项目的 pom.xml 或 build.gradle 文件中添加以下依赖项，以使用新的 MySQL JDBC 驱动程序：

Maven：

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.26</version>
</dependency>

Gradle：

implementation 'mysql:mysql-connector-java:8.0.26'

在你的 Java 代码中，你可以使用以下语句加载 MySQL JDBC 驱动程序：

Class.forName("com.mysql.cj.jdbc.Driver");

如果你使用的是 Java 6 或更高版本，也可以使用以下语句自动加载 MySQL JDBC 驱动程序，无需显式加载：

// 注册 MySQL JDBC 驱动程序
DriverManager.registerDriver(new com.mysql.cj.jdbc.Driver());

在你的应用程序中，你还需要提供正确的 JDBC 连接字符串、用户名和密码，以连接到 MySQL 数据库。例如：

String url = "jdbc:mysql://localhost:3306/mydatabase";
String user = "myuser";
String password = "mypassword";

Connection conn = DriverManager.getConnection(url, user, password);

希望能帮助到你

• 你可以看下这个问题的回答https://ask.csdn.net/questions/7700913
• 这篇博客你也可以参考下：（重点）MySQL（入门篇22）JDBC下载和驱动教程 ，第一个JDBC程序，驱动步骤的解析。
• 除此之外, 这篇博客: 通过MySQL可以查出数据，但是jdbc本身就是没有结果中的 配置文件如下： 部分也许能够解决你的问题, 你可以仔细阅读以下内容或跳转源博客中阅读:
  

•   # Example MySQL config file for medium systems.  
    #  
    # This is for a system with little memory (32M - 64M) where MySQL plays  
    # an important part, or systems up to 128M where MySQL is used together with  
    # other programs (such as a web server)  
    #  
    # MySQL programs look for option files in a set of  
    # locations which depend on the deployment platform.  
    # You can copy this option file to one of those  
    # locations. For information about these locations, see:  
    # http://dev.mysql.com/doc/mysql/en/option-files.html  
    #  
    # In this file, you can use all long options that a program supports.  
    # If you want to know which options a program supports, run the program  
    # with the "--help" option.  
    # The following options will be passed to all MySQL clients  
    [client]
    default-character-set=utf8
    #password   = your_password  
    port        = 3306  
    socket      = /tmp/mysql.sock   
    # Here follows entries for some specific programs  
    # The MySQL server  
    [mysqld]
    character-set-server=utf8
    init_connect='SET NAMES utf8
    port        = 3306  
    socket      = /tmp/mysql.sock  
    skip-external-locking  
    key_buffer_size = 16M  
    max_allowed_packet = 1M  
    table_open_cache = 64  
    sort_buffer_size = 512K  
    net_buffer_length = 8K  
    read_buffer_size = 256K  
    read_rnd_buffer_size = 512K  
    myisam_sort_buffer_size = 8M  
    character-set-server=utf8  
    init_connect='SET NAMES utf8' 
  # Don't listen on a TCP/IP port at all. This can be a security enhancement,  
  # if all processes that need to connect to mysqld run on the same host.  
  # All interaction with mysqld must be made via Unix sockets or named pipes.  
  # Note that using this option without enabling named pipes on Windows  
  # (via the "enable-named-pipe" option) will render mysqld useless!  
  #   
  #skip-networking  
    
    # Replication Master Server (default)  
    # binary logging is required for replication  
    log-bin=mysql-bin  
      
      # binary logging format - mixed recommended  
      binlog_format=mixed  
        
        # required unique id between 1 and 2^32 - 1  
        # defaults to 1 if master-host is not set  
        # but will not function as a master if omitted  
        server-id   = 1  
          
      # Replication Slave (comment out master section to use this)  
      #  
      # To configure this host as a replication slave, you can choose between  
      # two methods :  
      #  
      # 1) Use the CHANGE MASTER TO command (fully described in our manual) -  
      #    the syntax is:  
      #  
      #    CHANGE MASTER TO MASTER_HOST=<host>, MASTER_PORT=<port>,  
      #    MASTER_USER=<user>, MASTER_PASSWORD=<password> ;  
      #  
      #    where you replace <host>, <user>, <password> by quoted strings and  
      #    <port> by the master's port number (3306 by default).  
      #  
      #    Example:  
      #  
      #    CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,  
      #    MASTER_USER='joe', MASTER_PASSWORD='secret';  
      #  
      # OR  
      #  
      # 2) Set the variables below. However, in case you choose this method, then  
      #    start replication for the first time (even unsuccessfully, for example  
      #    if you mistyped the password in master-password and the slave fails to  
      #    connect), the slave will create a master.info file, and any later  
      #    change in this file to the variables' values below will be ignored and  
      #    overridden by the content of the master.info file, unless you shutdown  
      #    the slave server, delete master.info and restart the slaver server.  
      #    For that reason, you may want to leave the lines below untouched  
      #    (commented) and instead use CHANGE MASTER TO (see above)  
      #  
      # required unique id between 2 and 2^32 - 1  
      # (and different from the master)  
      # defaults to 2 if master-host is set  
      # but will not function as a slave if omitted  
      #server-id       = 2  
      #  
      # The replication master for this slave - required  
      #master-host     =   <hostname>  
      #  
      # The username the slave will use for authentication when connecting  
      # to the master - required  
      #master-user     =   <username>  
      #  
      # The password the slave will authenticate with when connecting to  
      # the master - required  
      #master-password =   <password>  
      #  
      # The port the master is listening on.  
      # optional - defaults to 3306  
      #master-port     =  <port>  
      #  
      # binary logging - not required for slaves, but recommended  
      #log-bin=mysql-bin  
        
        # Uncomment the following if you are using InnoDB tables  
        #innodb_data_home_dir = /usr/local/mysql/data  
        #innodb_data_file_path = ibdata1:10M:autoextend  
        #innodb_log_group_home_dir = /usr/local/mysql/data  
        # You can set .._buffer_pool_size up to 50 - 80 %  
        # of RAM but beware of setting memory usage too high  
        #innodb_buffer_pool_size = 16M  
        #innodb_additional_mem_pool_size = 2M  
        # Set .._log_file_size to 25 % of buffer pool size  
        #innodb_log_file_size = 5M  
        #innodb_log_buffer_size = 8M  
        #innodb_flush_log_at_trx_commit = 1  
        #innodb_lock_wait_timeout = 50  
          
          [mysqldump]  
          quick  
          max_allowed_packet = 16M  
            
            [mysql]  
            no-auto-rehash  
            # Remove the next comment character if you are not familiar with SQL  
            #safe-updates  
            default-character-set=utf8   
              
          [myisamchk]  
          key_buffer_size = 20M  
          sort_buffer_size = 20M  
          read_buffer = 2M  
          write_buffer = 2M  
            
            [mysqlhotcopy]  
            interactive-timeout
  

• 您还可以看一下 邵发老师的Java学习指南(8) MySQL数据库与JDBC框架课程中的 关于本篇小节, 巩固相关知识点