1.2java开发环境搭建

操作系统win7  jdk8

下载jdk  ，oracle官网https://www.oracle.com/index.html 

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下载jdk8的最新版本，当前为jdk-8u151-windows-x64.exe
本地创建jdk安装目录 例如 D:\java8\jdk  D:\java8\jre ，并安装jdk到创建目录，程序首先安装JDK然后自动弹出安装JRE。
计算机 - 属性 - 高级系统设置 - 环境变量
新建系统变量 
变量名 JAVA_HOME
变量值 D:\java8\jdk      // 要根据自己的实际路径配置
修改系统变量
变量名 Path
变量值最前面添加 %JAVA_HOME%\bin;

验证："开始"->"运行"，键入"cmd"；键入命令: java -version、java、javac 几个命令验证是否为安装的java版本

jdk1.5开始不需要配置classpath，编译器会自动去寻找 tools.jar

开发工具

notepad++

Eclipse

安装：下载，解压到安装目录

Eclipse的JDK版本要求

Eclipse 4.6 (Neon)
Eclipse 4.6 (Neon)is scheduled for release on June 22, 2016.
A Java 8 JRE/JDK is required to run all Neon packages based on Eclipse 4.6
Eclipse 4.5 (Mars)
Eclipse 4.5 (Mars) was released on June 24, 2015.
A Java 7 JRE/JDK is required for all Mars package downloads based on Eclipse 4.5
Eclipse 4.4 (Luna)
Eclipse 4.4 (Luna) was released on June 25, 2014.
A Java 7 JRE/JDK is required for most of the Luna package downloads based on Eclipse 4.4
Eclipse 4.3 (Kepler)
Eclipse 4.3 (Kepler) was released in June 2013.
A Java 6 JRE/JDK is recommended for Eclipse 4.3