ClassNotFoundException: com.mysql.jdbc.Driver. JDBC MySQL driver for web application

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Solution 1

You missed mysql-connector-j jar file in your classpath. Use "java -cp .:mysql.jar...". Ou. It's a webapp! Then put mysql jar file to WEB-INF/lib folder.

Solution 2

Right click Libraries ->Add JAR/Folder and choose mysql-connector-java.jar file

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adit
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adit

Updated on July 05, 2022

Comments

  • adit
    adit almost 2 years

    So I have a .jar file for the MySQL JDBC driver, it is under my libraries source folder and I have the following code:

    public static Connection getConnection() throws SQLException {
            Connection conn = null;
            try{
                Class.forName("com.mysql.jdbc.Driver").newInstance();
                String url = "jdbc:mysql://50.56.81.42:3306/GUEST_BOOK";
                String user = "user";
                String password = "pass";
    
                conn = (Connection) DriverManager.getConnection(url, user, password);
            }catch(ClassNotFoundException e){
                e.printStackTrace();
            }catch(InstantiationException e){
                e.printStackTrace();
            }catch(IllegalAccessException e){
                e.printStackTrace();
            }
                return conn;
    
        }
    

    However, it always gives me this error:

    INFO: Server startup in 645 ms
    java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1523)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:169)
        at gbook.DbHelper.getConnection(DbHelper.java:14)
        at gbook.DbHelper.getGuestBook(DbHelper.java:51)
        at org.apache.jsp.index_jsp._jspService(index_jsp.java:83)
        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
        at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:433)
        at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389)
        at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
        at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
        at java.lang.Thread.run(Thread.java:680)
    Dec 1, 2011 1:41:05 PM org.apache.catalina.core.StandardWrapperValve invoke
    SEVERE: Servlet.service() for servlet [jsp] in context with path [/JDBC-MySQL] threw exception [javax.servlet.ServletException: java.lang.NoClassDefFoundError: com/mysql/jdbc/Connection] with root cause
    java.lang.ClassNotFoundException: com.mysql.jdbc.Connection
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1523)
        at gbook.DbHelper.getGuestBook(DbHelper.java:52)
        at org.apache.jsp.index_jsp._jspService(index_jsp.java:83)
        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    

    Here's how I added the jar file. I created a lib folder and put the jar inside and then I go to configure build path in eclipse and added the jar inside the lib folder to the project.

  • TechDog
    TechDog almost 9 years
    Works perfect after placing connector under "WEB-INF/lib"