各位大侠,
小弟今天按书上的方法为 MySQL数据库驱动 配置环境变量-->书上说在CLASSPATH后添加MySQL驱动 jar文件的路径进去,我照样子添加了,然后运行了下面代码:书本上说如果能正常运行说明添加环境变量成功。可是,我在CMD命令行能正常编译运行,在Eclipse中编译出现异常,求解释。。。。我刚学 ^_^! 谢谢 ^_^!
代码:
public class ConnectionDemo01 {
public static final String DBDRIVER="org.gjt.mm.mysql.Driver";
public static void main(String[] args){
try{
Class.forName(DBDRIVER);
}catch(ClassNotFoundException e){
e.printStackTrace();
}
}
}
在Eclipse中出现java.lang.ClassNotFoundException: org.gjt.mm.mysql.Driver异常。
------解决方案--------------------
- Java code
package sample;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class MysqlLianjie { public static void main(String[] args) throws ClassNotFoundException { String Driver = "com.mysql.jdbc.Driver"; String url="jdbc:mysql://localhost:3306/kb"; String username = "root"; String password = "long"; Connection con = null; Statement s = null; ResultSet rs = null; try { Class.forName(Driver); con = DriverManager.getConnection(url, username, password); System.out.println("数据库连接成功!"); s = con.createStatement();// rs = s.executeQuery("select * from users"); String query = "create table consumer2(model INTEGER(4),speed INTEGER(4), ram INTEGER(4),hd INTEGER(4),price INTEGER(6))"; s.executeUpdate(query); System.out.println("创建表成功!"); } catch (SQLException e) { System.out.println("SQLException:" + e.getMessage()); } }}
------解决方案--------------------
在Eclipse中需要添加build path,然后add external jars,这样classpath就不用配置了。