📅 最后修改于: 2020-11-18 07:51:38 🧑 作者: Mango
Ant构建文件是用XML编写的，它不允许像使用您喜欢的编程语言一样声明变量。但是，正如您可能想像的那样，如果Ant允许声明诸如项目名称，项目源目录等变量，这将很有用。
Ant使用允许您指定属性的property元素。这允许将属性从一个版本更改为另一个版本，或从一个环境更改为另一个环境。
默认情况下，Ant提供以下可在构建文件中使用的预定义属性-
| Sr.No. | Properties & Description |
|---|---|
| 1 |
ant.file The full location of the build file. |
| 2 |
ant.version The version of the Apache Ant installation. |
| 3 |
basedir The basedir of the build, as specified in the basedir attribute of the project element. |
| 4 |
ant.java.version The version of the JDK that is used by Ant. |
| 5 |
ant.project.name The name of the project, as specified in the name atrribute of the project element. |
| 6 |
ant.project.default-target The default target of the current project. |
| 7 |
ant.project.invoked-targets Comma separated list of the targets that were invoked in the current project. |
| 8 |
ant.core.lib The full location of the Ant jar file. |
| 9 |
ant.home The home directory of Ant installation. |
| 10 |
ant.library.dir The home directory for Ant library files – typically ANT_HOME/lib folder. |
Ant还使系统属性(例如：file.separator)可用于构建文件。
除上述内容外，用户还可以使用property元素定义其他属性。以下示例显示如何定义一个名为sitename的属性-
Apache Ant version is ${ant.version} - You are at ${sitename}
在上述构建文件上运行Ant将产生以下输出-
C:\>ant
Buildfile: C:\build.xml
info: [echo] Apache Ant version is Apache Ant(TM) version 1.8.2
compiled on December 20 2010 - You are at www.tutorialspoint.com
BUILD SUCCESSFUL
Total time: 0 seconds
C:\>