The Apache Commons project differs from many other Apache hosted projects because it is comprised of multiple, independently released packages. This page provides an overview of the Commons components that are currently available.
| Components | |
|---|---|
| Attributes | Runtime API to metadata attributes such as doclet tags. |
| BCEL | Byte Code Engineering Library - analyze, create, and manipulate Java class files |
| BeanUtils | Easy-to-use wrappers around the Java reflection and introspection APIs. |
| Betwixt | Services for mapping JavaBeans to XML documents, and vice versa. |
| BSF | Bean Scripting Framework - interface to scripting languages, including JSR-223 |
| Chain | Chain of Responsibility pattern implemention. |
| CLI | Command Line arguments parser. |
| Codec | General encoding/decoding algorithms (for example phonetic, base64, URL). |
| Collections | Extends or augments the Java Collections Framework. |
| Compress | Defines an API for working with tar, zip and bzip2 files. |
| Configuration | Reading of configuration/preferences files in various formats. |
| CSV | Component for reading and writing comma separated value files. |
| Daemon | Alternative invocation mechanism for unix-daemon-like java code. |
| DBCP | Database connection pooling services. |
| DbUtils | JDBC helper library. |
| Digester | XML-to-Java-object mapping utility. |
| Discovery | Tools for locating resources by mapping service/reference names to resource names. |
| EL | Interpreter for the Expression Language defined by the JSP 2.0 specification. |
| Library for sending e-mail from Java. | |
| Exec | API for dealing with external process execution and environment management in Java. |
| FileUpload | File upload capability for your servlets and web applications. |
| Functor | A functor is a function that can be manipulated as an object, or an object representing a single, generic function. |
| Imaging (previously called Sanselan) | A pure-Java image library. |
| IO | Collection of I/O utilities. |
| JCI | Java Compiler Interface |
| JCS | Java Caching System |
| Jelly | XML based scripting and processing engine. |
| Jexl | Expression language which extends the Expression Language of the JSTL. |
| JXPath | Utilities for manipulating Java Beans using the XPath syntax. |
| Lang | Provides extra functionality for classes in java.lang. |
| Launcher | Cross platform Java application launcher. |
| Logging | Wrapper around a variety of logging API implementations. |
| Math | Lightweight, self-contained mathematics and statistics components. |
| Modeler | Mechanisms to create Model MBeans compatible with JMX specification. |
| Net | Collection of network utilities and protocol implementations. |
| OGNL | An Object-Graph Navigation Language |
| Pool | Generic object pooling component. |
| Primitives | Smaller, faster and easier to work with types supporting Java primitive types. |
| Proxy | Library for creating dynamic proxies. |
| Sanselan (now called Imaging) | A pure-Java image library. |
| SCXML | An implementation of the State Chart XML specification aimed at creating and maintaining a Java SCXML engine. It is capable of executing a state machine defined using a SCXML document, and abstracts out the environment interfaces. |
| Transaction | Implementations for multi level locks, transactional collections and transactional file access. |
| Validator | Framework to define validators and validation rules in an xml file. |
| VFS | Virtual File System component for treating files, FTP, SMB, ZIP and such like as a single logical file system. |
The following components were part of Apache Commons but have moved elsewhere: