The peaberry project is an extension library for Google-Guice that supports dependency injection of dynamic services. It provides OSGi integration out of the box, and has plug-in support for other registry-based service frameworks. It ships as an OSGi bundle that can be dropped into any R4 framework, such as Apache Felix or Eclipse/Equinox. You can also use peaberry outside of OSGi.
Transmorph is a Java library used to convert a Java object of one type into an object of another type (with another signature, possibly parameterized). It supports conversion for primitives and objects, conversion to multidimensional arrays, conversion to parameterized collections and types, and jars for JDK 1.4 and JDK 1.5. It has no dependencies. It is easy to add more converters. It can convert to a type given either its Java type (class) or signature.
With MetaModel, you use a type-safe SQL-like API for querying any datastore. It is a data access framework providing a common interface for exploration and querying of different types of datastores. It isn't a data mapping framework. Instead, it emphasizes abstraction of metadata and the ability to add data sources at runtime, making MetaModel great for generic data processing applications, but less so for applications modeled around a particular domain.
jSieve is a Java implementation of the Sieve mail filtering language defined by RFC 3028. Sieve is an extensible mail filtering language. Its limited expressiveness (no loops or variables and no tests with side effects) allows user created scripts to be run safely on email servers. Sieve is targeted at the final delivery phase (where an incoming email is transferred to a user's mailbox). jSieve is implemented as a language processor that can be plugged into any Internet mail application to add Sieve support.