Ant vs Maven

Apache Ant

• Ant doesn’t have formal conventions such as a common project directory structure; you have to tell Ant exactly where to find the source and where to put the output. Informal conventions have emerged over time, but they haven’t been codified into the product.
• Ant is procedural; you have to tell Ant exactly what to do and when to do it. You have to tell it to compile, then copy, then compress.
• Ant doesn’t have a lifecycle; you have to define goals and goal dependencies. You have to attach a sequence of tasks to each goal manually.

Apache Maven

• Maven has conventions: in the example, it already knew where your source code was because you followed the convention. It put the bytecode in target/classes, and it produced a JAR file in target.
• Maven is declarative; all you had to do was create a pom.xml file and put your source in the default directory. Maven took care of the rest.
• Maven has a lifecycle, which you invoked when you executed mvn install. This command told Maven to execute a series of sequence steps until it reached the lifecycle. As a side effect of this journey through the lifecycle, Maven executed a number of default plugin goals that did things such as compile and create a JAR.