Apache Commons
Apache Commons是Apache的一个开源项目，主要致力于各种可重用的Java组件。主要由以下三部分构成：
The Commons Proper- 一个可重用的Java组件库（已经开发完的项目，一般我们导入相关jar包就可以使用）The Commons Sandbox- Java组件开发工作区（正在开发的项目）The Commons Dormant- 当前处于非活跃的Java组件库（其实就是还没开始开发）
The Commons Proper
一般我们比较关注就是The Commons Proper，这里面都是现成的组件库，基本上拿来就可以使用，应该导入其提供的相关jar包，就可以用了。所以我们着重介绍 The Commons Proper项目
The Commons Proper 是一个为开发者提供合作和资源共享的地方。下面列出已经release的Java组件项目
| Components | Description | Latest Version | Released |
| BCEL | Byte Code Engineering Library - analyze, create, and manipulate Java class files | 5.2 | 2007-06-14 |
| BeanUtils | Easy-to-use wrappers around the Java reflection and introspection APIs. | 1.9.2 | 2014-05-29 |
| BSF | Bean Scripting Framework - interface to scripting languages, including JSR-223 | 3.1 | 2010-24-06 |
| Chain | Chain of Responsibility pattern implemention. | 1.2 | 2008-06-02 |
| CLI | Command Line arguments parser. | 1.2 | 2009-03-19 |
| Codec | General encoding/decoding algorithms (for example phonetic, base64, URL). | 1.9 | 2013-12-25 |
| Collections | Extends or augments the Java Collections Framework. | 4.0 | 2013-11-24 |
| Compress | Defines an API for working with tar, zip and bzip2 files. | 1.8.1 | 2014-05-14 |
| Configuration | Reading of configuration/preferences files in various formats. | 1.10 | 2013-10-27 |
| CSV | Component for reading and writing comma separated value files. | N/A | N/A |
| Daemon | Alternative invocation mechanism for unix-daemon-like java code. | 1.0.15 | 2013-03-04 |
| DBCP | Database connection pooling services. | 2.0.1 | 2014-05-24 |
| DbUtils | JDBC helper library. | 1.6 | 2014-07-20 |
| Digester | XML-to-Java-object mapping utility. | 3.2 | 2011-12-13 |
| Discovery | Tools for locating resources by mapping service/reference names to resource names. | 0.5 | 2011-04-28 |
| EL | Interpreter for the Expression Language defined by the JSP 2.0 specification. | 1.0 | 2003-06-18 |
| Library for sending e-mail from Java. | 1.3.3 | 2014-07-11 | |
| Exec | API for dealing with external process execution and environment management in Java. | 1.2 | 2014-01-02 |
| FileUpload | File upload capability for your servlets and web applications. | 1.3.1 | 2014-02-07 |
| Functor | A functor is a function that can be manipulated as an object, or an object representing a single, generic function. | N/A | N/A |
| Imaging (previously called Sanselan) | A pure-Java image library. | N/A | N/A |
| IO | Collection of I/O utilities. | 2.4 | 2012-06-12 |
| JCI | Java Compiler Interface | 1.1 | 2013-10-14 |
| JCS | Java Caching System | 1.3 | 2007-06-05 |
| Jelly | XML based scripting and processing engine. | 1.0 | 2005-06-16 |
| Jexl | Expression language which extends the Expression Language of the JSTL. | 2.1.1 | 2011-12-24 |
| JXPath | Utilities for manipulating Java Beans using the XPath syntax. | 1.3 | 2008-08-14 |
| Lang | Provides extra functionality for classes in java.lang. | 3.3.2 | 2014-04-09 |
| Launcher | Cross platform Java application launcher. | 1.1 | 2004-08-22 |
| Logging | Wrapper around a variety of logging API implementations. | 1.2 | 2014-07-11 |
| Math | Lightweight, self-contained mathematics and statistics components. | 3.3 | 2014-05-14 |
| Modeler | Mechanisms to create Model MBeans compatible with JMX specification. | 2.0.1 | 2007-06-25 |
| Net | Collection of network utilities and protocol implementations. | 3.3 | 2013-06-12 |
| OGNL | An Object-Graph Navigation Language | N/A | N/A |
| Pool | Generic object pooling component. | 2.2 | 2014-02-24 |
| Primitives | Smaller, faster and easier to work with types supporting Java primitive types. | 1.0 | 2003-11-05 |
| Proxy | Library for creating dynamic proxies. | 1.0 | 2008-02-28 |
| 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. | 0.9 | 2008-12-01 |
| Validator | Framework to define validators and validation rules in an xml file. | 1.4.0 | 2012-02-03 |
| VFS | Virtual File System component for treating files, FTP, SMB, ZIP and such like as a single logical file system. | 2.0 | 2011-08-24 |
| Weaver | Provides an easy way to enhance (weave) compiled bytecode. | 1.0 | 2014-03-16 |
这些项目都已经是release版本，可以直接用。剩下的The Commons Sandbox和The Commons Dormant就不介绍了。之后的文章，我会分析一下第一个项目Java BCEL，这是一个Java字节码设计库，可以用来修改，创建，操作Java类文件。
参考链接
Java Apache 开源项目简介
时间： 2024-12-24 09:54:21