the commons project already has more than three dozen components; some have been developed from scratch, and other have been pulled out of bigger projects under jarkata.
the components that are part of jakarta commons are categorized into two parts:
commons proper: this section holds components that are in a production-ready state. experimentation and changes will be minimal and systematic with these components.
sandbox: the sandbox components are those that hold a lot of promise but still in an incomplete stage. many of the sandbox components are still on the dramming border or in beta and alpha releases.
the following are the various components currently featured in the commons proper:
beanutils:javabeans adhereing to standard naming conventions as specified in the javabean specification and having private member variables with a public get method to fetch the value of the variable and a set method to set it are often used in java development.
betwixt: the betwixt component provides a way to easily convet javabeans into xml.
cli: this component makes working with command line arguments simple and systematic. it provides a methodology to specify arguments,their usahe and access to arguments.
codec:codec provides implementations for common encoders and decoders.
collections:the collections components go beyond what is offered by the java collection framework and provides many classes that offer useful collections and utilities.
dbcp:the database connection pool component provides the functionality of pooling database connection and optimally utilizing them. database connections are precious resources that need to be created and used wisely.
dbutils: the dbutils component is a handy set of classes capable of easily handling most of the routine tasks aht need to be performed while accessing a database using java database connectivity.
digester: creating ,parsing and using xml files can be quite a pain if only the basic apis are used. digester makes working with xml quite simple and is of great use, especially while retrieving information from configuration files.
discovery:the discovery component is meant to ease discovery of implementation for various interfaces.
el:an important addition to java server pafge is the support for an expression language. the el component is an expression lanuage interpreter.
fileupload:the fileupload component can provide file upload capability to web applications.
httpclient: the httpclient component goes beyond hypertext transfer protocol features offered by the net component and provided many features required by a java client communicationg using http.
jelly:jelly is a component that can convert xml into executable code. jelly has many subelements that use the core concepty to achieve different ends.
jexl:jexl stands for jave expression language. the jexl component provides an expression lanuage engine that implements an extended version of the expression lanuage of jsp standard tag libraries.
jxpath:jxpath is an interpreter for xml.
org.apache.commons.lang: this package provides the classes you are likely to use most often while working with the lang component. the builder package consists of classes that help in creating commonly used metheds.
the validator component is a framework you can use to take the drudgery out of writing validation code. the validator component comes with a built-in validation capability for some common validations. the validator component began as part of the struts framework.
the advantages of using the validator framework are as follows:
validaton rules can be defined in xml files.
validation rules can be changed without having to touch the source code.
built-in validations handle most of the common scenarios.
pooling is an important concept and if used wisely can reduce resource consumprion as well as boosts your application's performance. the pool component consists of two package
rg.apchae.commons.pool and and org.apche.commomns.poll.impl. the package org.apche.commons.pool provides interface and base implementations and the org.apache.commons.pool.impl package provides implementations of a few types of object pooling that are possible.
the objectpool inerface is what defines the methods that each pooling implementation has to provide. the interface is simple enough, the methods borrowobject and returnobject are the two you will use the most.
the dbutils component is a nice ,simple component that does nothing but jsut makes many jdbc tasks a shade easier for the developer. although many persistence frameworks and packages are aviable these days that aim at making data persistence a littler eaiser,jdbc still is very much the bread and butter for most java and java2 enterprise edition developers.
分享到:
相关推荐
apache commons jar(commons所有的jar包,从官网下载提供给大家) 因为涉及jar太多,包括有src源代码,只需要3分,希望大家理解,我也是从官网花了很长时间才一个一个下完,需要的请自取。全部是zip文件,每个对应的...
apache commons all 中文api合集
apache Commons Lang 2.4 API apache Commons Lang 2.4 API
主要介绍了Apache Commons Math3探索之多项式曲线拟合实现代码,小编觉得挺不错的,这里分享给大家,供需要的朋友参考。
Apache Commons API简介,主要介绍Apache Commons API所包含的包,后续更新补充各类的简介和使用方法
Apache Commons IO 2.5 (要求 JDK 1.6),IOUtils,FileUtils,jar包下载
apache commons 工具包中提供的一个针对配置文件动态修改的工具类
apache commons jexl 表达解析工具
Apache Commons Collections,commons-collections-3.2.1和commons-collections4-4.0,含jar包及源码和api文档。
Apache Commons Pool 2.4.1,编译 jedis 2.7.2 时候使用。
Apache Commons Lang 3.4 API 帮助文档,英文
Apache Commons工具集简介详述各种apache提供的工具类
apache commons dbcp api_zh
apache commons math api_zh
Apache Commons Logging 1.2
apache commons jar(commons所有的jar包,从官网下载提供给大家) 因为涉及jar太多,包括有src源代码,只需要3分,希望大家理解,我也是从官网花了很长时间才一个一个下完,需要的请自取。全部是zip文件,每个对应的...
apache commons dbutils api_zh
commons-lang3.3.1.jar、Apache Commons包中的一个,包含了一些数据类型工具类,是java.lang.*的扩展。必须使用的jar包。为JRE5.0+的更好的版本所提供 Jar文件包含的类: META-INF/MANIFEST.MFMETA-INF/LICENSE....
apache commons.fileupload上传组件在上传文件时,在调用parseRequest方法时,先将输入流上传到服务器临时目录,在之后的文件处理过程中,再将临时目录下保存的文件复制到指定的目录,多了一道转储步骤。本实现抽取...
Apache Commons是Apache软件基金会的项目,曾隶属于Jakarta项目。Commons的目的是提供可重用的、开源的Java代码。 Apache Commons项目的由三部分组成: The Commons Proper - 一个可重用的Java组件库。(已经发布过的...