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  • Re: Common Java Mistakes

    Problem description: JDBC Connection Error
    Problem category: Runtime Error

    Diagnosis Difficulty: Easy to medium
    Difficulty to Fix: Easy

    When trying to connect to a database using JDBC, a java.lang.ClassNotFound exception is thrown at the point where the database driver should be loaded (eg when Class.forName is called for the appropriate database driver).

    Suggested fixes

    This typically occurs when the database driver is not on the classpath. There are two steps to fix this problem. First, download the driver for the database you wish to access (mysql, postgres, Oracle, Microsoft SQL). Second, place the downloaded jar file on the classpath of the program. Oracle provides detailed instructions for doing this on the command line. For those using Eclipse, right click the project and select Properties. Go to Java Build Path -> Libraries -> Add External Jar and select the driver jar.
    This article was originally published in forum thread: Common Java Mistakes started by helloworld922 View original post