java.lang.ClassNotFoundException: com.mysql.jdbc.Driver (maven + jboss)

Question

maven pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>

<groupId>Test</groupId>
<artifactId>Test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>

<name>Test</name>
<url>http://maven.apache.org</url>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
            </configuration>
        </plugin>
    </plugins>
</build>
<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>3.8.1</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.18</version>
    </dependency>
</dependencies>

In code Im trying to execute Class.forName("com.mysql.jdbc.Driver").

I get this:

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

But I have checked I have mysql.jar in jboss-as-7.0.2.Final\standalone\deployments\Test.war\WEB-INF\lib and it has com.mysql.jdbc.Driver class.

The `servlet-api` dependency should be marked as `provided`, btw. — Dave Newton, Nov 23 '11 at 14:25
What is the exact name of `mysql.jar` file that you have in `..WEB-INF\lib` ? — ring bearer, Nov 23 '11 at 14:30
@Dᴀᴠᴇ Nᴇᴡᴛᴏɴ Thx, I did not know, I will try.@ring bearer mysql-connector-java-5.1.18.jar — itun, Nov 23 '11 at 14:36
@itun - how are you executing your code? via the build or IDE or command line ? — ring bearer, Nov 23 '11 at 14:44
via IDE which has specific JBoss Maven plugin to deploy projects — itun, Nov 23 '11 at 14:49
Do you have the mysql jar added to your project's build path ( for example in eclipse) ? — ring bearer, Nov 23 '11 at 15:45

score 4 · Accepted Answer · answered Nov 23 '11 at 17:04

4

As a rule you should not be including your JDBC drivers in your war file.

I suggest you mark the driver as provided and add it to the lib directory of the server.

PS. I'm not sure why you would be using

Class.forName("com.mysql.jdbc.Driver")

in your code. Why not let the contain manage your connections and transactions?

answered Nov 23 '11 at 17:04

James DW

1,815
16
21

for JBoss AS7, there is no lib directory on the server, so this answer won't fix it either. Correct way is to use data sources provided by the container. – eis Apr 03 '13 at 06:34

score 1 · Answer 2 · answered Apr 03 '13 at 06:30

This error occurred because your mysql jar is not on your run-time class-path. If you are using maven,

Open your EAR/web project properties
Click on "Deployment Assembly"
Click on "Add..."
Select on "Java Build Path Entries"
Click on "Next"
Select "Maven Dependencies"
Click "Finish"

score 0 · Answer 3 · answered Apr 03 '13 at 06:35

It seems you are using JBoss AS7. Check instructions here: https://community.jboss.org/wiki/DataSourceConfigurationInAS7

Basically, you should

Install mysql connector
Create a data source using it
Refer to that data source using JNDI configuration

Class.forName() is an idiom commonly used when data sources are not provided by the container. In modern Java EE servers, they are provided.

score 0 · Answer 4 · answered Jul 12 '13 at 11:25

I had a slightly different use case. I was using apache's BasicDataSource in a stand-alone application.

I got this exception because I was calling setDriverClassName with com.mysql.jdbc.Driver.class.toString() instead of "com.mysql.jdbc.Drive" as a String (so compile time check ensures that there is no typo or Driver's location didn't change in a version upgrade... etc).

But!

When you look Driver's implementation it has a static initialization block:

static {
  try {
    java.sql.DriverManager.registerDriver(new Driver());
  } catch (SQLException E) {
    throw new RuntimeException("Can't register driver!");
  }
}

When I wrote com.mysql.jdbc.Driver.class.toString() this initialization block executed too early and caused later on misleading ClassNotFoundException to be thrown. Once I switched to "com.mysql.jdbc.Driver" my application started to work.

This is a case when static becomes evil :)

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver (maven + jboss)

4 Answers4

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