Perfmon4j is a suite of performance monitoring tools that are intended to be used to diagnose performance bottlenecks and monitor throughput and response time in production Java applications. Its main features include servlet response time monitoring, detailed thread trace sampling, Java instrumentation that enables Package, Class, and Method monitoring without code modification, snapshot monitoring of system metrics including Garbage Collection, Memory Pools, etc., an API for applying additional monitoring points via method annotations or in-line timers, and support for dynamically enabling monitors in running applications.

Z1 CertServer (formerly Z1 Backbone Of Trust CertServer) is a server-based software solution for the storage and administration of X.509 certificates and OpenPGP keys. It targets customers who use a public key infrastructure (based on X.509 or OpenPGP) and who want to take advantage of the central access to certificates. It also automatically validates certificates by querying certificate revocation lists (CRLs) from the issuing trust centers, or by using OCSP (Online Certificate Status Protocol). Java and C/C++ SDKs are provided. It is available as pre-installed hardware or a virtual appliance, with evaluation packages for Debian and Solaris.

Niocchi is a Java crawler library implementing synchronous I/O multiplexing. This specific type of implementation allows crawling tens of thousands of hosts in parallel on a single low end server. Niocchi has been designed for big search engines that need to crawl massive amount of data, but can also be used to write no-frills crawlers.

jOpenTTDLib is a Java library that polls OpenTTD servers for statistics on games in progress.
This includes data on the map and how all the companies are faring. On top of this functionality, the games can be continually polled and game events are generated and listeners notified.

Property Binder is a Java library that provides typed access to entries in properties files. It offers such access by allowing a programmer to provide it a Java interface whose methods represent the keys of the properties file. The methods can be annotated to indicate what property the method represents, what default value(s) it should assume if the property is not present, and what pattern separates the individual values of multi-valued properties.

SimpleTemplate is a simple template engine written in Java. You can generate formatted text from a Java bean. You can use it for generating XML files, Web sites, etc. It features simple template directives, user-selectable template directive separators, alias creation using with and set directives, support for indexing into arrays, collections, and maps, looping on an array or a collection, a simple include mechanism to reuse template files, conditional evaluation using if and ifelse, and custom list separation settings (prefix, suffix, and separators). Template files can be read from the filesystem, class path, or just a string. Support for methods, aka. sub templates.

GNU WebSocket4J is a WebSocket protocol implementation in Java. It allows you to build Web applications that interact with applications running in a JVM. GNU WebSocket4J implements both the server and client side of the protocol, so it can be used to build both WebSocket servers and clients.

InfinityDB is an all-Java B+Tree database engine that is embeddable in the smallest to the largest applications that run on hand held devices, workstations, servers, or in distributed systems. InfinityDB provides a data integrity guarantee through all non-media failures, provides a simple API with only a few basic methods, and requires no administrative support. Version 2 offers full ACID transactionality without a log and with fine-grained locks. Programmers can easily superimpose their own data model or employ the Entity-Attribute-Value model by direct low-level access. The basic engine provides multi-valued or set attributes, all primitive Java types, unlimited Large Objects, heterogenous values, composite keys (Entities) and values, and unlimited sparse attributes, all extensible in-place with no schema changes.