簡(jiǎn)介
JavaEE在開發(fā)的時(shí)候，如果是系統(tǒng)內(nèi)部常量，一般提倡用枚舉常量類，寫在單獨(dú)的類中，但是經(jīng)常要修改的變量,比如數(shù)據(jù)源配置，如果存在數(shù)據(jù)庫(kù)中，有種浪費(fèi)。但是存在TXT中擴(kuò)展性不好，就筆者觀察，一般的程序員都喜歡把經(jīng)常修改的常量存在xml文件或者Properties文件。
存在xml文件最大的好處是擴(kuò)展性很好，一般用sax或者dom這兩個(gè)方向的框架，比如DOM4J,JDOM等。Sun推出的JAXM(Java API for XML Messaging)也是用的DOM4J。由于SAX的處理方式類似流媒體，是逐行的，不需要全部加載。而DOM是全部加載在內(nèi)存，生成樹。因而SAX的讀取比DOM性能好，但是修改的話DOM略勝一籌。Properties文件的擴(kuò)展性不如xml，但是有很多xml沒法實(shí)現(xiàn)的優(yōu)勢(shì)，比如加密之類的~
Helloworld
筆者根據(jù)自己開發(fā)中感受，寫了一個(gè)工具包，用來體現(xiàn)讀取xml或者Properties的流程，大家在使用的時(shí)候記得修改文件路徑。一共包含五個(gè)文件.本demo主要是用來模擬讀取數(shù)據(jù)庫(kù)的賬戶和密碼的，讀者可以在此基礎(chǔ)上擴(kuò)展。
Statistical-Learning-Theory
The goal of statistical learning theory is to study, in a statistical
framework, the Properties of learning algorithms. In particular,
most results take the form of so-called error bounds. This tutorial introduces
the techniques that are used to obtain such results.
This should again compile without problems. We finally need to configure a logging system - Hibernate uses
commons logging and leaves you the choice between Log4j and JDK 1.4 logging. Most developers prefer
Log4j: copy log4j.Properties
In 揚(yáng)erformance of multi-carrier DS CDMA Systems?we apply a multi-carrier signaling technique to a direct-sequence CDMA system, where a data sequence multiplied by a spreading sequence modulates multiple carriers, rather than a single carrier. The receiver provides a correlator for each carrier, and the outputs of the correlators are combined with a maximal-ratio combiner. This type of signaling has the desirable Properties of exhibiting a narrowband interference suppression effect, along with robustness to fading, without requiring the use of either an explicit RAKE structure or an interference suppression filter.
When trying to extract information from SAR images, we need to distinguish
two types of image property. The more important is where Properties of the
scene (e.g., its dielectric constant, its geometry, its motion, etc.) produce effects
in the image measurements or examination of the image then can provide
information about the scene. The second is generated purely by the system
and the signal processing.
Functions are mappings from one Manifold to another. Discrete Functions are functions which can be represented using a finite number of values. Given the finite extent of computer memory, algorithms which compute a function that satisfies some special Properties are computing a discrete function which approximates a continuous function. Computing the function involves writing a set of equations that may be solved for the values representing the function.
