1.什么是J2ME:
J2ME(Java 2 Micro Edition)是Java 2的一個(gè)組成部分，它與J2SE、J2EE并稱。根據(jù)Sun的定義：J2ME是一種高度優(yōu)化的Java運(yùn)行環(huán)境，主要針對(duì)消費(fèi)類(lèi)電子設(shè)備的，例如蜂窩電話和可視電話、數(shù)字機(jī)頂盒、汽車(chē)導(dǎo)航系統(tǒng)等等。J2ME技術(shù)在1999年的JavaOne Developer Conference大會(huì)上正式推出，它將Java語(yǔ)言的與平臺(tái)無(wú)關(guān)的特性移植到小型電子設(shè)備上,允許移動(dòng)無(wú)線設(shè)備之間共享應(yīng)用程序。
J2ME在設(shè)計(jì)其規(guī)格的時(shí)候，遵循著對(duì)于各種不同的裝置而造出一個(gè)單一的開(kāi)發(fā)系統(tǒng)是沒(méi)有意義的事」這個(gè)基本原則。于是 J2ME 先將所有的嵌入式裝置大體上區(qū)分為兩種 :一種是運(yùn)算功能有限、電力供應(yīng)也有限的嵌入式裝置(比方說(shuō)PDA 、手機(jī))；另外一種則是運(yùn)算能力相對(duì)較佳、并請(qǐng)?jiān)陔娏?yīng)上相對(duì)比較充足的嵌入式裝置 (比方說(shuō)冷氣機(jī)、電冰箱、電視機(jī)上盒 (set-top box))。因?yàn)檫@兩種型態(tài)的嵌入式裝置，所以Java 引入了一個(gè)叫做Configuration 的概念，然后把上述運(yùn)算功能有限、電力有限的嵌入式裝置定義Connected Limited Device Configuration(CLDC)規(guī)格之中；而另

1. what is the J2ME
J2ME (Java 2 Micro Edition) is a Java 2 as an integral part of it with J2SE, J2EE said. According to Sun's definition: J2ME is a highly optimized Java runtime environment, mainly for consumer electronics devices such as cellular phones and video phones, digital set-top boxes, car navigation systems and so on. J2ME technology in 1999, the JavaOne Developer Conference on the formal launch of the General Assembly, which will of the Java language and platform-independent features into a small electronic device that allows mobile wireless devices sharing between applications.
J2ME in its design specifications, to follow a "variety of devices to create a single development system is meaningless" the basic principles. So first of all J2ME embedded devices generally divided into two types: One is the limited computing, power supply is also limited embedded devices (for example, PDA, cell phone); another kind of computing power is relatively better, And in the power supply is relatively sufficient for embedded devices (for example, air conditioners, refrigerators, TV set-top boxes (set-top box)). Because these two types of embedded devices, Java is why the introduction of a concept called Configuratio