写的jdbc工具类，前期写了测试正确，但发布到tomcat中就报这样的错误。
javax.servlet.ServletException: Servlet execution threw an exception
root cause
java.lang.NoClassDefFoundError: Could not initialize class cn.elvis.utils.JdbcUtils
cn.elvis.dao.impl.UserDaoImpl.find(UserDaoImpl.java:180)
cn.elvis.service.impl.BusinessServiceImpl.register(BusinessServiceImpl.java:15)
cn.elvis.web.controller.RegisterServlet.doGet(RegisterServlet.java:40)
cn.elvis.web.controller.RegisterServlet.doPost(RegisterServlet.java:77)
javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
下面是我的工具类代码
- Java code
public final class JdbcUtils { private static String driver="com.microsoft.sqlserver.jdbc.SQLServerDriver"; private static String url="jdbc:sqlserver://localhost:1433;DatabaseName=JspWebDb"; private static String user="sa"; private static String psw="12345"; private JdbcUtils(){} private static JdbcUtils instanse=new JdbcUtils(); public static JdbcUtils getInstanse() { return instanse; } static{ try{ Class.forName(driver); } catch(ClassNotFoundException e) { throw new ExceptionInInitializerError(e); } } public static Connection getConnection() throws SQLException { return DriverManager.getConnection(url,user,psw); } public static void free(ResultSet rs,Statement st,Connection conn) { if(rs!=null) try { rs.close(); } catch (SQLException e) { e.printStackTrace(); } finally { if(st!=null) try { st.close(); } catch (SQLException e) { e.printStackTrace(); } finally { if(conn!=null) try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } } } }------解决方案--------------------------------------------------------