Apache Ant is a Java-based build tool. In theory, it is kind of like make, without make's wrinkles.
Why?
Why another build tool when there is already make, gnumake, nmake, jam, and others? Because all those tools have limitations that Ant's original author couldn't live with when developing software across multiple platforms. Make-like tools are inherently shell-based: they evaluate a set of dependencies, then execute commands not unlike what you would issue on a shell. This means that you can easily extend these tools by using or writing any program for the OS that you are working on; however, this also means that you limit yourself to the OS, or at least the OS type, such as Unix, that you are working on.
Makefiles are inherently evil as well. Anybody who has worked on them for any time has run into the dreaded tab problem. "Is my command not executing because I have a space in front of my tab?!!" said the original author of Ant way too many times. Tools like Jam took care of this to a great degree, but still have yet another format to use and remember.
Ant is different. Instead of a model where it is extended with shell-based commands, Ant is extended using Java classes. Instead of writing shell commands, the configuration files are XML-based, calling out a target tree where various tasks get executed. Each task is run by an object that implements a particular Task interface.
Granted, this removes some of the expressive power that is inherent in being able to construct a shell command such as `find . -name foo -exec rm {}`, but it gives you the ability to be cross-platform - to work anywhere and everywhere. And hey, if you really need to execute a shell command, Ant has an task that allows different commands to be executed based on the OS it is executing on.
介紹
Apache Ant是一個基於java構建工具，在理論上講， 他是編譯的一種， 但是沒有編譯痕跡
現在的編譯工具繁多， 如make, gnumake, nmake, jam,等等：爲什麼我們還要做一個ant來編譯呢？ 因爲，其他的工具都存在一個侷限性：不能跨越平臺操作， 這也是ant作者所不能忍受的。
Ant 是一個基於javaclass文件擴展的編譯工具， 不想很多編譯工具， 是基於一個命令外殼程序， 取而代之， ant 是以一個xml配置文件， 寫入一組目標樹來執行編譯過程的，每一個目標樹是一個特別的任務接口，你可以在任何地方來使用這個工具， 他是真正跨平臺的，如果你一定堅持要用命令行來執行編譯過程，好， ant也有一個特殊的任務叫exec，可以在操作系統上執行不同的任務。