Question

I am getting well-known NoClassDefFoundError: com/mysql/jdbc/StringUtils, but my case is little different: I am not using MySQL at all.

I’m working with PostgreSQL 9.1 database using JDK 1.6.
On my computer everything works perfectly (PostgreSQL driver is loaded, no classpath issues etc.), but I have to upload my project to my University’s servers, where I am getting the following error:

java.lang.NoClassDefFoundError: Could not initialize class com.mysql.jdbc.StringUtils

Here is a full stack trace:

com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:286)
java.sql.DriverManager.getConnection(DriverManager.java:582)
java.sql.DriverManager.getConnection(DriverManager.java:185)
elections.ConnectionManager.getConnection(ConnectionManager.java:29)
elections.daos.LoginDAO.login(LoginDAO.java:23) 
elections.controllers.LoginController.doPost(LoginController.java:46) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:641) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:722) 
sun.reflect.GeneratedMethodAccessor35.invoke(Unknown Source) 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) 
java.lang.reflect.Method.invoke(Method.java:597) 
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:274) 
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:271) 
java.security.AccessController.doPrivileged(Native Method) 
javax.security.auth.Subject.doAsPrivileged(Subject.java:517) 
org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:306) 
org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:166)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:299) 
org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:57) 
org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:193) 
org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:189) 
java.security.AccessController.doPrivileged(Native Method) 
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188) 
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:208) 
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) 
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) 
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) 
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) 
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927) 
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) 
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) 
org.apache.coyote.ajp.AjpAprProcessor.process(AjpAprProcessor.java:197) 
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579) 
org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1770) 
java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) 
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) 
java.lang.Thread.run(Thread.java:662)

Here’s my class which provides connection (It’s my first JDBC project; I know that code below is not threadsafe; I’m going to rewrite it using Connection Pooling, but first I need to get it to work…)

static Connection conn;

public static Connection getConnection() throws Exception {
    try {

        String url = "jdbc:postgresql://host/database";
        String username = "username";
        String pwd = "password";

        Class.forName("org.postgresql.Driver");

        try {
            conn = DriverManager.getConnection(url, username, pwd);
        } catch (SQLException e) {
            e.printStackTrace();
            throw e;
        }
    } catch (ClassNotFoundException e) {
        throw e;
    }
    return conn;
}

I did huge search on the internet but I seem to be the only man in the world with such issue… Everybody else has this problem with MySQL only.

I have even tried to put MySQL driver (containing the lacking com.mysql.jdbc.StringUtils class) into WEB-INF/lib folder, but this didn’t help.

Only useful information I have found is that probably error is hidden somewhere else (that means, some class that com.mysql.jdbc.StringUtils depends on couldn;t be loaded), but I don’t know where to search.

I really don’t understand why MySQL classes are searched for, while I use PostgreSQL only.

Any kind of help would be appreciated! 🙂

Answer 1

Ok, It turned out to be permissions issue with Tomcat Security Manager. As soon as admin will examine what the exact reason was, I’ll post it here and accept the best answer.