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Java 错误:应为类、接口或枚举_Java_Mysql - Fatal编程技术网

Java 错误:应为类、接口或枚举

Java 错误:应为类、接口或枚举,java,mysql,Java,Mysql,/*试图连接mysql,但出现错误:应为类、接口或枚举*/ public class mysqlconnect{ try { // loads com.mysql.jdbc.Driver into memory Class.forName("com.mysql.jdbc.Driver"); } catch (ClassNotFoundException cn

/*试图连接mysql,但出现错误:应为类、接口或枚举*/

public class mysqlconnect{
         try
             {
            // loads com.mysql.jdbc.Driver into memory
            Class.forName("com.mysql.jdbc.Driver");
              } 

        catch (ClassNotFoundException cnf) 
          {
            System.out.println("Driver could not be loaded: " + cnf);
           }
        }

错误是因为类中缺少大括号。这就是为什么编译器无法理解它是类、枚举还是接口定义。所以,它抛出了这个错误。修好它们。而且,你可以这样做

public class mysqlconnect {

   static{ 
       try
         {
        // loads com.mysql.jdbc.Driver into memory
        Class.forName("com.mysql.jdbc.Driver");
          } 
    catch (ClassNotFoundException cnf) 
      {
        System.out.println("Driver could not be loaded: " + cnf);
       }
    }

}

或者您需要一个单独的方法将
try
catch
块放入其中。除此之外,您还需要大写类名,如
MySqlConnect
,以遵循
Java
命名约定您可以通过此链接清楚地了解如何在Java中使用mysql连接数据库

先决条件:


用于mysql的JDBC驱动程序。您可以根据您的平台从此链接下载驱动程序

java和javascript完全不同。这是无效的,您需要在类中使用一个方法(然后将代码放入该方法)。您不能将语句置于方法之外,它需要一些标识符,以便可以引用。从main方法调用它是不可能的。您应该阅读Java教程