多个xml文件定义ant配置文件
下面我们给出一个相对复杂的build.xml文件：
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE project [
<!ENTITY build-abstract SYSTEM "file:./build-abstract.xml">
]>
<project name="projectTemplate" default="init" basedir=".">
<target name="init" depends="init.variables">
<property name="lib.dir" value="lib"/>
<echo message="Hello ${user.name}! lib.dir is set to ${lib.dir}" />
<echo message="build.dir is set to ${build.dir} in build-abstract.xml " >
</echo>
</target>
<target name=" clean" depends="init" >
<del dir="${build.dir}"/>
</target>
&build-abstract;
</project>
<!DOCTYPE project [
<!ENTITY build-abstract SYSTEM "file:./build-abstract.xml">
]>
<project name="projectTemplate" default="init" basedir=".">
<target name="init" depends="init.variables">
<property name="lib.dir" value="lib"/>
<echo message="Hello ${user.name}! lib.dir is set to ${lib.dir}" />
<echo message="build.dir is set to ${build.dir} in build-abstract.xml " >
</echo>
</target>
<target name=" clean" depends="init" >
<del dir="${build.dir}"/>
</target>
&build-abstract;
</project>
其中<!ENTITY build-abstract SYSTEM "file:./build-abstract.xml">定义了一个名为build-abstract的实体，其内容为当前目录下的build-abstract.xml文件。&build-abstract;引用了这个实体，这样在build.xml文件就可以用build-abstract.xml定义的目标啦。
下面是build-abstract.xml的内容：
<target name="init.variables">
<property name="build.dir" value="tempbuild"/>
</target>
