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var emailAbstract="在本教程中，您将要使用 Java 2 平台，Micro 版 (Java 2 Platform, Micro Edition, J2ME) -- Sun Microsystem 的 Java 2 平台最新版本为手持计算机开发一个基本绘图应用程序。我们将首先说明 J2ME 的背景，研究 J2ME 配置和简表，然后指导您建立自己的开发环境。 接着，我们将研究 K 虚拟机 GUI 开发，使用连接限制设备配置 (Connected Limited Device Configuration, CLDC) API 开发一个基本绘图应用程序。我们还将讨论移动信息设备简表 (Mobile Information Device, MIDP) 用户界面开发，这种开发也要用到 CLDC。最后，我们将简单讨论一下连接设备配置 (Connected Device Configuration, CDC)，但我们不开发一个简单的应用程序，因为 CDC 主要面向大型设备。";
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var menu2blurb="J2ME 概述";
var menu3blurb="开发 J2ME 应用程序";
var menu4blurb="J2ME 配置";
var menu5blurb="J2ME 简表";
var menu6blurb="设置您的开发环境";
var menu7blurb="CLDC API";
var menu8blurb="使用 KJava GUI 组件的开发";
var menu9blurb="使用 KJava 事件处理的开发";
var menu10blurb="MIDP API";
var menu11blurb="CDC API";
var menu12blurb="总结";
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配置将基本运行时环境定义为一组核心类和一个运行在特定类型设备上的特定 JVM。虽然还可能在将来定义其他的配置，但当前
J2ME
存在两种配置：
</p><ul><li><b>连接限制设备配置 (CLDC)</b>
特别与 KVM
一起用于内存有限的 16 位或 32 位设备。这是用于开发小型
J2ME 应用程序的配置（虚拟机）。（从开发的角度来看）它的大小限制让它比
CDC 更有趣、更具挑战性。CLDC
同时还是用于开发绘图工具应用程序的配置。 Palm 电脑便是一个运行小应用程序的小型无线设备的示例。我们将在
<a href="j-j2me-4-1.shtml">J2ME 配置</a>一章中深入介绍 CLDC。<br x="7"><br x="7"</li><li><b>连接设备配置 (CDC)</b>
与 C 虚拟机 (CVM) 一起使用，用于要求内存超过 2 兆的 32 位体系结构。互联网电视机顶盒便是这类设备的一个示例。虽然稍后我们将在 <a href="j-j2me-11-1.shtml">CDC API</a>
一章中简要介绍 CDC，但它并不在本教程的范围内。</li></ul>
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