J2SE_1-2

1998 年 12 月 8 日发布，代号为 Playground 。该版本到 J2SE 5.0 为止的后续版本被更名为 Java 2 ，而版本名称“J2SE”（Java 2 平台，标准版）取代 JDK 以区别 J2EE（Java 2 平台，企业版）和 J2ME（Java 2 Platform，Micro Edition）基础平台。这是 Java 的一个非常重要的版本，它将 Java 平台的大小增加至原先的三倍，在 59 个程序包中达到了 1520 个类。主要增加包括：[9] (opens new window)

# 主要特性

strictfp 关键字

参考 java中不常见的关键字：strictfp，transient (opens new window)
主类别中集成了 Swing (opens new window) "Swing (Java)")图像化 API
首次为 Sun 提供的 JVM 配备 JIT(Just In Time) (opens new window)编译器
Java plug-in (opens new window)（即 Java Applet）
Java IDL (opens new window)，一个与 CORBA (opens new window) 互通的接口描述语言 (opens new window)实现
Java集合框架 (opens new window)，如新增 HashMap 替代旧的 HashTable（常用）;
对打包的 Java 文件进行数字签名;
JFC(Java Foundation Classes), 包括 Swing 1.0, 拖放和 Java2D 类库;
JDBC 中引入可滚动结果集,BLOB,CLOB,批量更新和用户自定义类型;
Applet 中添加声音支持.

# Java 在 1.2 细分为三个平台

As work progressed within Sun Microsystems on Java 1.2, a decision was made to rebrand Java and to make major changes in the way Java was packaged and licensed. Java 1.2 became simply Java 2, although the JDK and JRE versions remained at 1.2. More importantly, however, the Java platform was split into three editions:

■■ Java 2 Standard Edition (J2SE) is for conventional desktop application development. Swing has been folded into the core Java classes, and a number of new classes have been added to enhance application development even more than what Java 1.1 offered.
■■ Java 2 Enterprise Edition (J2EE) is a superset of J2SE that is geared toward enterprise programming with an emphasis on server-side development using Enterprise JavaBeans (EJBs), web applications (servlets and JavaServer Pages), CORBA, and Extensible Markup Language (XML).
■■ Java 2 Micro Edition (J2ME) is a subset of J2SE that is geared toward embedded and handheld devices that cannot support a full J2SE implementation.