​

特点

 大小写敏感；

 不可改变，先到先得，谁先设定，之后的都不能改变。

怎样设置

1 、设置 name 和 value 属性值，比如： <property name="srcdir" value="${basedir}/src"/>

2 、 设置 name 和 refid 属性值，比如： <property name="srcpath" refid="dao.compile.classpath"/> ，其中dao.compile.classpath 在别的地方定义。

3 、设置 name 和 location 属性值，比如： <property name="srcdir" location="src"/> ，即将 srcdir 的值设     置为：当前项目根目录的 /src 目录。

4 、设置 file 属性值，比如： <property file="build.properties"/> ， 导入 build.properties 属性文件中的属性值

5 、设置 resource 属性值，比如： <propety resource="build.properties"/>, 导入 build.properties 属性文件中的属性值

6 、设置 url 属性值，比如： <property url="http://www.blogjava.net/wiflish/build.properties"/>, 导入http://www.blogjava.net/wiflish/build.properties 属性文件中的属性值。

7 、设置环境变量，比如： <property environment="env"/> ，设置系统的环境变量为前缀 env.

     <property name="tomcat.home" value="${env.CATALINA_HOME}"/> 将系统的 tomcat 安装目录设置到     tomcat.home 属性中。

内置属性

 

Ant’s built-in properties:

 


basedir



The absolute path of the project’s basedir.



ant.file



The absolute path of the buildfile.



ant.version



The version of Ant.



ant.project.name



The name of the project that is currently executing.



ant.project.default-target



The name of the currently executing project’s default target.



ant.project.invoked-targets



A comma separated list of the targets that have been specified on the command line when invoking the current.



ant.java.version



The JVM version Ant detected.



ant.core.lib



The absolute path of the ant.jar file.


 

System properties  

 


java.version



Java Runtime Environment version



java.vendor



Java Runtime Environment vendor



java.vendor.url



Java vendor URL



java.home



Java installation directory



java.vm.specification.version



Java Virtual Machine specification version



java.vm.specification.vendor



Java Virtual Machine specification vendor



java.vm.specification.name



Java Virtual Machine specification name



java.vm.version



Java Virtual Machine implementation version



java.vm.vendor



Java Virtual Machine implementation vendor



java.vm.name



Java Virtual Machine implementation name



java.specification.version



Java Runtime Environment specification version



java.specification.vendor



Java Runtime Environment specification vendor



java.specification.name



Java Runtime Environment specification name



java.class.version



Java class format version number



java.class.path        



Java class path



java.library.path



List of paths to search when loading libraries



java.io.tmpdir



Default temp file path



java.compiler



Name of JIT compiler to use



java.ext.dirs



Path of extension directory or directories



os.name



Operating system name



os.arch



Operating system architecture



os.version



Operating system version



file.separator



File separator ("/" on UNIX)



path.separator



Path separator (":" on UNIX)



line.separator



Line separator ("\n" on UNIX)



user.name



User's account name



user.home



User's home directory



user.dir



User's current working directory


 

用法

${key_name}，如：${os.name}，它将得到当前操作系统的名称。

需注意

1. 内置属性basedir

 -- 不需要定义就可以直接使用，${basedir}，得到当前工程的绝对路径

 -- 当在<project>标签的basedir属性中指定basedir时，之后工程中出现的所有相对路径都是相对于这个basedir所指向的路径，且${basedir}的值也将变为<project>标签中的basedir属性所指定的值。

 

2. property的不变性在使用<available><ant><antcall>时会被打破

 

3. 可以在命令行通过-DpropertyName=propertyValue的方式指定property，注意，-D于propertyName之间没有空格，使用这种方式指定的属性最先被赋值，它是在执行build文件之前就已经赋值了的。

 

Q&A

How can I do something like  ​​<property name="prop" value="${${anotherprop}}"/>​​   (double expanding the property)?

Without any external help you can not.

With <script/>, which needs external libraries, you can do

 




Xml代码  ​​ant property总结_xml​​


  2. <script language="javascript">  
  3.     propname = project.getProperty("anotherprop");  
  4.     project.setNewProperty("prop", propname);  
  5. </script>  


 

With AntContrib (external task library) you can do ​​<propertycopy name="prop" from="${anotherprop}"/>​​ .

With Ant 1.6 you can simulate the AntContribs <propertycopy> and avoid the need of an external library:

 




Xml代码  ​​ant property总结_xml​​


  2. <macrodef name="propertycopy">  
  3.   <attribute name="name"/>  
  4.   <attribute name="from"/>  
  5.   <sequential>  
  6.     <property name="@{name}" value="${@{from}}"/>  
  7.   </sequential>  
  8. </macrodef>   


 

With the 'props' antlib (external, but also from Ant) you could do the dereferencing with  ​​${${anotherprop}​​   - not just in the property task - instead everywhere in your buildfile (after registering the required property helper).

 




Xml代码  ​​ant property总结_xml​​


  2. <propertyhelper>  
  3.   <props:nested />  
  4. </propertyhelper>  
  5. <property name="foo" value="foo.value" />  
  6. <property name="var" value="foo" />  
  7. <echo> ${${var}} = foo.value </echo>   


 

With  ​​Flaka​​   (external Ant Plugin) you could do the dereferencing with  ​​#{${anotherprop}}​​   - not just in flaka tasks, but all tasks after installing flaka's property handler.

 




Xml代码  ​​ant property总结_xml​​


  2. <project xmlns:fl="antlib:it.haefelinger.flaka">  
  3.   <fl:install-property-handler/>  
  4.   <property name="foo" value="foo.value"/>  
  5.   <property name="var" value="foo" />  
  6.   <property name="buildtype" value="test"/>  
  7.   <property name="appserv_test" value="//testserver"/>  
  8.   <echo>  
  9.     #{${var}} = foo.value  
  10.     <!-- nested property -->  
  11.     #{appserv_${buildtype}}  
  12.   </echo>  
  13. </project>