SAP Hybris install.bat工作原理分析

以Windows平台为例，install.bat的内容：

@echo off
SET INSTALLER_WORKING_DIR=%~dp0
javac %INSTALLER_WORKING_DIR:~0,-1%\JavaVersionChecker.java
java -classpath "%INSTALLER_WORKING_DIR:~0,-1%" JavaVersionChecker
IF errorlevel 0 (
java -classpath ";%INSTALLER_WORKING_DIR:~0,-1%/libs/commons-cli-1.2.jar;%INSTALLER_WORKING_DIR:~0,-1%/libs/commons-lang-2.6.jar;%INSTALLER_WORKING_DIR:~0,-1%/libs/groovy-all-2.4.10.jar;%INSTALLER_WORKING_DIR:~0,-1%/libs/installer-6.7.0.3.jar" de.hybris.installer.CmdHandler %*
)

• SET INSTALLER_WORKING_DIR=%~dp0: 将变量INSTALLER_WORKING_DIR的值设置为install.bat文件所在的目录，比如C:\Code\hybris670\installer

• javac %INSTALLER_WORKING_DIR:~0,-1%\JavaVersionChecker.java

相当于执行：javac C:\Code\hybris670\installer\JavaVersionChecker.java

• java -classpath "%INSTALLER_WORKING_DIR:~0,-1%" JavaVersionChecker
  相当于执行：
  java -classpath "C:\Code\hybris670\installer" JavaVersionChecker

• java -classpath ";%INSTALLER_WORKING_DIR:_{0,-1%/libs/commons-cli-1.2.jar;%INSTALLER_WORKING_DIR:}0,-1%/libs/commons-lang-2.6.jar;%INSTALLER_WORKING_DIR:_{0,-1%/libs/groovy-all-2.4.10.jar;%INSTALLER_WORKING_DIR:}0,-1%/libs/installer-6.7.0.3.jar" de.hybris.installer.CmdHandler %*: 执行libs文件夹里的jar包进行安装