GenericTools is the set of classes that provide basic
infrastructure for using tools in standard Java SE Velocity
projects, as well as a set of tools for use in generic Velocity
templates. These tools have no Java EE dependencies and are often
safe to use as "singletons". Some of them are not thread-safe to
allow both a no-arg constructor and configurability, but the
state-changing methods are declared protected with the exception
of configure(Map) which is--by default--rendered useless after
being used just once. If you require strict thread-safety,
be cautious in using any configurable tools and consider
the abilities of template authors to prevent circumvention
of the lockdown placed on configuration methods.
The default configuration provided for GenericTools is
here. It includes all of the tools listed
The dependencies required for GenericTools vary somewhat depending on which
tools you use, whether you will rely on core tool management infrastructure,
and if so, how you choose to configure your toolbox. More details can be found
- For creating s
to easily alternate over a set of values.
- For simplifying reflective lookup of information about
Classes and their fields, methods and constructors.
- For convenient access to Context data and meta-data.
- For converting String values to richer object types.
- For manipulating, formatting, and comparing dates.
- For controlling display of references (e.g. truncating values,
"pretty printing" lists, and displaying alternates when a reference is null).
- For common escaping needs in Velocity templates (e.g. escaping
- For (easy) access to static fields in a class, such as string
- A convenience tool to use with #foreach loops. It wraps a list
with a custom iterator to provide greater control, allowing loops
to end early, skip ahead and more.
- For creating and manipulating URIs and URLs. The API for this tool is
designed to closely resemble that of the VelocityView tool of the same name.
- For working with arrays and lists, treats both transparently
- For performing math functions.
- For formatting and converting numbers.
- To evaluate and render arbitrary strings of VTL, including
- For simplified access to ResourceBundles for
internationalization or other dynamic content needs.
- Used to sort collections (or arrays, iterators, etc) on
any arbitary set of properties exposed by the objects contained
within the collection.
- For reading/navigating XML files. This uses dom4j under the
covers and provides complete XPath support.