apache common 项目研究

    http://commons.apache.org/
 
包括
 

<table class="bodytable" border="0"><tbody><tr class="a"><th>components</th><th> </th></tr><tr class="b"><td>attributes</td><td>runtime api to metadata attributes such as doclet tags.</td></tr><tr class="a"><td>beanutils</td><td>easy-to-use wrappers around the java reflection and introspection apis.</td></tr><tr class="b"><td>betwixt</td><td>services for mapping javabeans to xml documents, and vice versa.</td></tr><tr class="a"><td>chain</td><td>chain of responsibility pattern implemention.</td></tr><tr class="b"><td>cli</td><td>command line arguments parser.</td></tr><tr class="a"><td>codec</td><td>general encoding/decoding algorithms (for example phonetic, base64, url).</td></tr><tr class="b"><td>collections</td><td>extends or augments the java collections framework.</td></tr><tr class="a"><td>compress</td><td>defines an api for working with tar, zip and bzip2 files.</td></tr><tr class="b"><td>configuration</td><td>reading of configuration/preferences files in various formats.</td></tr><tr class="a"><td>daemon</td><td>alternative invocation mechanism for unix-daemon-like java code.</td></tr><tr class="b"><td>dbcp</td><td>database connection pooling services.</td></tr><tr class="a"><td>dbutils</td><td>jdbc helper library.</td></tr><tr class="b"><td>digester</td><td>xml-to-java-object mapping utility.</td></tr><tr class="a"><td>discovery</td><td>tools for locating resources by mapping service/reference names to resource names.</td></tr><tr class="b"><td>el</td><td>interpreter for the expression language defined by the jsp 2.0 specification.</td></tr><tr class="a"><td>email</td><td>library for sending e-mail from java.</td></tr><tr class="b"><td>exec</td><td>api for dealing with external process execution and environment management in java.</td></tr><tr class="a"><td>fileupload</td><td>file upload capability for your servlets and web applications.</td></tr><tr class="b"><td>io</td><td>collection of i/o utilities.</td></tr><tr class="a"><td>jci</td><td>java compiler interface</td></tr><tr class="b"><td>jelly</td><td>xml based scripting and processing engine.</td></tr><tr class="a"><td>jexl</td><td>expression language which extends the expression language of the jstl.</td></tr><tr class="b"><td>jxpath</td><td>utilities for manipulating java beans using the xpath syntax.</td></tr><tr class="a"><td>lang</td><td>provides extra functionality for classes in java.lang.</td></tr><tr class="b"><td>launcher</td><td>cross platform java application launcher.</td></tr><tr class="a"><td>logging</td><td>wrapper around a variety of logging api implementations.</td></tr><tr class="b"><td>math</td><td>lightweight, self-contained mathematics and statistics components.</td></tr><tr class="a"><td>modeler</td><td>mechanisms to create model mbeans compatible with jmx specification.</td></tr><tr class="b"><td>net</td><td>collection of network utilities and protocol implementations.</td></tr><tr class="a"><td>pool</td><td>generic object pooling component.</td></tr><tr class="b"><td>primitives</td><td>smaller, faster and easier to work with types supporting java primitive types.</td></tr><tr class="a"><td>proxy</td><td>library for creating dynamic proxies.</td></tr><tr class="b"><td>sanselan</td><td>a pure-java image library.</td></tr><tr class="a"><td>scxml</td><td>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.</td></tr><tr class="b"><td>transaction</td><td>implementations for multi level locks, transactional collections and transactional file access.</td></tr><tr class="a"><td>validator</td><td>framework to define validators and validation rules in an xml file.</td></tr><tr class="b"><td>vfs</td><td>virtual file system component for treating files, ftp, smb, zip and such like as a single logical file system.</td></tr></tbody></table>