eclipse中老出现 Could not find the main class. Program will exit.是什么原因？

import java.sql.*;

public class TestJDBC {

public static void main(String[] args) throws Exception {
Class.forName("oracle.jdbc.driver.OracleDriver");
//new oracle.jdbc.driver.OracleDriver(); //以上两种接口都可以
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@192.168.0.1:1521:orcluser", "scott", "5453752");

}

}

出现错误提示：
java.lang.UnsupportedClassVersionError: TestJDBC (Unsupported major.minor version 49.0)
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
Exception in thread "main"

这是什么原因呢？本人英语很菜，编程正学习中也很菜。。我在命令提示符里运行这段代码为什么就没问题呢？？我看视频教程上得老师写得也跟这完全一模一样，他得也没问题啊。。
我导入了classes12.jar，坏境变量也设置了。。但是还是没有用。。。