This is why rather than using the Java "classpath" environment variable, which is the traditional place to declare dependency repositories, Tomcat's start scripts ignore this variable and generate their own classpaths when they create Tomcat's "system" classloader. How Tomcat classpath usage differs from standard usageĮverything about Apache Tomcat aims to be as self-contained, intuitive, and automatic as possible, in an effort to standardize the configuration and deployment of web applications for efficient administration, while limiting access to different libraries for security and namespace reasons.
#Tomcat 7 vs tomcat 8 how to#
No information is provided on how to handle common less-than-ideal classpath situations such as outside dependencies, shared dependencies, or multiple versions of the same dependency. If you don't follow this best way, you're left in the dark, even if Tomcat technically supports the configuration you're trying to achieve. Tomcat's documentation and default configuration pushes for a "best" method of accomplishing certain things. The way Tomcat resolves classpaths has quietly changed with every major release Tomcat does not resolve classpaths in the same way as other Java programs There are three answers to this question, and we'll tackle each of them in turn: So why do so many experienced Java users who understand exactly what a classpath is and how it works run into problems with Tomcat? There are some interesting naming conventions having to do with directory structure, but they've been around forever. That's it - classpath: a path to a class (or collection of classes).
#Tomcat 7 vs tomcat 8 code#
Separating this responsibility from the program allows the Java code to reference the classes and packages in an abstract manner, allowing the program to be configured for use on any system. The classpath is always set from a source outside the program itself. Why classpaths cause trouble for Tomcat usersĪ classpath is an argument that tells the JVM where to find the classes and packages necessary to run a program. When you've finished reading, you'll not only have a fix to your problem that you can use right away, but also a better idea of how to avoid problems in the future by keeping Tomcat's idiosyncrasies in mind during your development process. In this article, we'll go over how Tomcat generates and utilizes classpaths, and then tackle all of the most common classpath-related issues one by one. Like many of the issues that trouble new Tomcat users, this problem is usually quite easy to fix - so easy that it's hard for users to understand the solution, because the documentation assumes that people will always pick the easiest way of doing things. To address the insecurity of the BinaryObjectHelper class, the following changes to DdlUtils have been made: (1) BinaryObjectsHelper.java has been deleted from the DdlUtils source repository and the DdlUtils feature of propagating data of SQL binary types is therefore no longer present in DdlUtils (2) The ddlutils-1.0 release has been removed from the Apache Release Distribution Infrastructure (3) The DdlUtils web site has been updated to indicate that DdlUtils is now available only as source code, not as a packaged release.Understanding the Tomcat classpath - Common problems and how to fix themĪ common question that pops up on lots of Apache Tomcat user forums is how to configure Tomcat's classpath to include this or that JAR file that is needed by a web application. Please note that DdlUtils is no longer being actively developed. The BinaryObjectsHelper class was insecure and used ObjectInputStream.readObject without validating that the input data was safe to deserialize. Īpache DB DdlUtils 1.0 included a BinaryObjectsHelper that was intended for use when migrating database data with a SQL data type of BINARY, VARBINARY, LONGVARBINARY, or BLOB between databases using the ddlutils features. Apache Sling Commons Messaging Mail 2.0 adds support for enabling server identity checks and these checks are enabled by default. A user could enable these checks nevertheless by accessing the session via the message created by SimpleMessageBuilder and setting the property to true. The SimpleMailService in Apache Sling Commons Messaging Mail 1.0 lacks an option to enable these checks for the shared mail session. For compatibility reasons these additional checks are disabled by default in JavaMail/Jakarta Mail. To reduce the risk of "man in the middle" attacks additional server identity checks must be performed when accessing mail servers. Apache Sling Commons Messaging Mail provides a simple layer on top of JavaMail/Jakarta Mail for OSGi to send mails via SMTPS.