錯誤而運行JDBC程序

我使用MySQL 5.5和MySQL連接器的Java-5.1.15。（兩者都安裝了新）錯誤而運行JDBC程序

我嘗試了JDBC程序通過使用記事本和命令提示符。

我的JDBC程序：

import java.sql.*; 
import java.io.*; 


public class MysqlConnect{ 
    public static void main(String[] args) { 

    System.out.println("MySQL Connect Example."); 
    Connection conn = null; 
    String url = "jdbc:mysql://localhost:3306/"; 
    String dbName = "employement"; 
    String driver = "com.mysql.jdbc.Driver"; 
    String userName = "root"; 
    String password = "12345"; 
    try { 
     Class.forName(driver).newInstance(); 
     conn = DriverManager.getConnection(url+dbName,userName,password); 
     System.out.println("Connected to the database"); 
     conn.close(); 
     System.out.println("Disconnected from database"); 
    } catch (Exception e) { 
     e.printStackTrace(); 
    } 
    } 
}

我創建了一個名爲到工作在MySQL數據庫....

我嘗試運行此程序...

C:\Users\Innodea\Desktop>javac MysqlConnect.java 

C:\Users\Innodea\Desktop>java MysqlConnect 
Exception in thread "main" java.lang.NoClassDefFoundError: MysqlConnect 
Caused by: java.lang.ClassNotFoundException: MysqlConnect 
     at java.net.URLClassLoader$1.run(URLClassLoader.java:202) 
     at java.security.AccessController.doPrivileged(Native Method) 
     at java.net.URLClassLoader.findClass(URLClassLoader.java:190) 
     at java.lang.ClassLoader.loadClass(ClassLoader.java:307) 
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) 
     at java.lang.ClassLoader.loadClass(ClassLoader.java:248) 
Could not find the main class: MysqlConnect. Program will exit.

如何清除這個錯誤？

而且我已經試過如下，

C:\Users\Innodea\Desktop>set classpath=C:\Program Files\MySQL\mysql-connector-ja 
va-5.1.15\mysql-connector-java-5.1.15.jar 

C:\Users\Innodea\Desktop>javac MysqlConnect.java 

C:\Users\Innodea\Desktop>java MysqlConnect 
Exception in thread "main" java.lang.NoClassDefFoundError: MysqlConnect 
Caused by: java.lang.ClassNotFoundException: MysqlConnect 
     at java.net.URLClassLoader$1.run(URLClassLoader.java:202) 
     at java.security.AccessController.doPrivileged(Native Method) 
     at java.net.URLClassLoader.findClass(URLClassLoader.java:190) 
     at java.lang.ClassLoader.loadClass(ClassLoader.java:307) 
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) 
     at java.lang.ClassLoader.loadClass(ClassLoader.java:248) 
Could not find the main class: MysqlConnect. Program will exit.

同樣也同樣發生錯誤，請幫我清除此錯誤和運行JDBC程序....

來源

2011-04-14 Ramprasad

java -cp .;C:\Program Files\MySQL\mysql-connector-java-5.1.15\mysql-connector-java-5.1.15.jar MysqlConnect

來源

2011-04-14 13:23:43 Nishant

使用-cp開關應該工作

 
java -cp=.;C:\Program Files\MySQL\mysql-connector-java-5.1.15\mysql-connector-java-5.1.15.jar MysqlConnect

它幾乎從來不需要設置CLASSPATH環境變量

來源

2011-04-14 13:23:59

嘗試使用此 -

java -cp %CLASSPATH%;.; MysqlConnect.java

或者補充。當前目錄 - 到classpath像

set classpath=C:\Program Files\MySQL\mysql-connector-ja va-5.1.15\mysql-connector-java-5.1.15.jar;.;

您當前的類也需要在類路徑中，因此點讀它。

來源

2011-04-14 13:24:27

錯誤而運行JDBC程序

回答

相關問題