最近捣鼓~！，各位高手指点・！

JAVA环境安装

1.目前J2SDK的最新版本是1.4.2_01，下载地址：http://java.sun.com/j2se/1.4.2/download.html 
Download NetBeans IDE v 3.5.1 with J2SE v 1.4.2 COBUNDLE 
采用包含了J2SE v 1.4.2的NetBeans IDE v 3.5.1
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2，安装！我的每一步：
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3，目录注意改下。“安装路径不宜有空格”！因为有时很难区分“Program Files”是代表一个文件夹还是代表“Program”和“Files”两个东西！
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4，配置环境变量
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5，新建系统变量
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6，建第一个系统变量：JAVA_HOME 值：C:\j2sdk_nb\j2sdk1.4.2
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7，建第二个系统变量：CLASSPATH 值：.;%JAVA_HOME%\lib
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8，注意！是修改，不是新建。
系统变量：PATH 的新值是在原有值前加上%JAVA_HOME%\bin;
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9、测试j2sdk的安装与环境变量设置是否正确
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所以显示完全和新建的吻合。OK！
接着就可以用一个.java来编译为class来执行了。