Question

我正在尝试通过servlet连接到mysql数据库。它总是给我上面的错误。我尝试了一切。

我下载了mysql-connector-java-8.0.11.jar并将其添加为外部jar。
我创建了一个名为'lib'的文件夹，并通过该文件夹添加了.jar文件。
一旦没有效果我删除了它们并尝试再次添加它。
我删除了当前服务器并重新安装。

public class flightDisplay extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        String url = "jdbc:mysql://localhost:3306/AirTicketsLK";
        String username = "root";
        String password = "";

        try {
            Class.forName("com.mysql.jdbc.Driver");
            Connection con = DriverManager.getConnection(url, username, password);
            Statement st = con.createStatement();
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } 
    }

这是控制台错误代码。

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1928)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1771)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Unknown Source)
    at flightDisplay.service(flightDisplay.java:48)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:498)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1139)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)

从try catch块中删除ClassNotFoundException后，这是浏览器错误代码。

类型例外报告

消息 Servlet执行引发异常

description 服务器遇到内部错误，无法完成此请求。

例外

javax.servlet.ServletException：Servlet执行引发异常     org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）

根本原因

java.lang.Error：未解决的编译问题：未处理的异常   类型ClassNotFoundException

flightDisplay.service（flightDisplay.java:48）     javax.servlet.http.HttpServlet.service（HttpServlet.java:731）     org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）

注意Apache中提供了根本原因的完整堆栈跟踪   Tomcat / 7.0.88日志。

java.lang.ClassNotFoundException：com.mysql.jdbc.Driver尝试了所有内容

0 个答案: