Apache Ant - Limitations

Limitations

• Ant build files are written in XML. For unfamiliar users, both XML itself and the complex structure (hierarchical, partly ordered, and pervasively cross-linked) of Ant documents can be a barrier to learning. A GUI called Antidote was available for a time, but never gained a following and has been retired from the Apache project. Moreover, the language of Ant is quite verbose, and the build files of large or complex projects become unmanageably large. Good design and modularization of build files can improve readability but not necessarily reduce size. Other build tools like Maven use more concise scripts at the expense of generality and flexibility.
• Many of the older tasks—the core ones that are used every day, such as , and —use default values for options that are not consistent with more recent versions of the tasks. Changing those defaults would break existing Ant scripts.
• When expanding properties in a string or text element, undefined properties are not raised as an error, but left as an unexpanded reference (e.g. ${unassigned.property}).
• Ant has limited fault handling rules, and no persistence of state, so it cannot be used as a workflow tool for any workflow other than classic build and test processes.
• Lazy property evaluation is not supported. For instance, when working within an Antcontrib loop, a property cannot be re-evaluated for a sub-value which may be part of the iteration. (Again you can workaround this depending on the third-party extension you're using; AntXtras flow-control tasksets do provide for cursor redefinition for loops.)
• In makefiles, any rule to create one file type from another file type can be written inline within the makefile. For example, you may transform a document into some other format by using rules to execute another tool. Creating a similar task in Ant is more complex: a separate task must be written in Java and included with the Ant build file in order to handle the same type of functionality. However, this separation can enhance the readability of the Ant script by hiding some of the details of how a task is executed on different platforms.

There exists a myriad of third-party Ant extensions (called antlibs) that provide much of the missing functionality. Also the Eclipse IDE can build and execute Ant scripts while the NetBeans IDE uses Ant for its internal build system. As both these IDEs are very popular development platforms, they can simplify Ant use significantly (as a bonus Ant scripts generated by NetBeans can be used outside of that IDE as standalone scripts).