Ant 简明教程

Ant - Using Token Filter

Ant 过滤器允许为当前项目设置一个标记过滤器。一个标记会用 @ 符号分隔，并且可以用属性文件读取。

Ant Filter allows to set a token filter for current project. A token is seperated by @ symbol and can be read using properties file as well.

Steps

  1. Step 1 − Define a token using @@.

This is a sample text written in @year@.

  1. Step 2 − Set the filter.

<filter token="year" value="2021"/>

  1. Step 3 − Use the filter. All tasks will replace the occurence of @year@ with 2021.

<copy todir="${dest.dir}" filtering="true">
   <fileset dir="${src.dir}"/>
</copy>

Filter Task Properties

以下是关键属性 −

Following are the key attributes −

Sr.No

Attribute & Description

1

token the token string without the separator chars (@)

2

value the string that should be put to replace the token when the file is copied.

3

filtersfile The file from which the filters must be read. This file must be a formatted as a property file.

为了让 Filter 任务正常工作，必须提供标记和值或过滤器文件。

Either token and value to be provided or filtersfile to Filter task to work properly.

Example

使用以下内容创建一个 src 文件夹和 text1.txt 文件 −

Create a src folder with text1.txt file with following contents −

This is a sample text written in @year@.

使用以下内容创建 build.xml −

Create build.xml with the following content −

<?xml version="1.0"?>
<project name="sample" basedir="." default="copy">
   <property name="src.dir" value="src"/>
   <property name="dest.dir" value="build"/>
   <target name="copy">
      <filter token="year" value="2021"/>
      <copy todir="${dest.dir}" filtering="true">
         <fileset dir="${src.dir}"/>
      </copy>
   </target>
</project>

Output

在上述构建文件上运行 Ant 会生成以下输出：

Running Ant on the above build file produces the following output −

F:\tutorialspoint\ant>ant
Buildfile: F:\tutorialspoint\ant\build.xml

copy:
   [copy] Copying 1 file to F:\tutorialspoint\ant\build

BUILD SUCCESSFUL
Total time: 1 second

F:\tutorialspoint\ant>

查看复制到 build 文件夹的文件的内容。

Verify the content of copied file to build folder.

This is a sample text written in 2021.