Gradle Beyond the Basics

Chapter 4. Dependency Management

Dependencies are a formidable challenge, whether they are dependencies in a Java build, in a Ruby project, or in any other kind of system. For one thing to depend on another means accepting the liability that the depended-on thing might not be available when we need it, might be expensive to obtain, or might not work in the way we expected. Programmers are painfully familiar with these costs.

Dependencies can seem like an annoyance—indeed, much of the undeserved criticism commonly directed against Maven focuses on dependency management—but they are an unavoidable fact of a complex ecosystem and are a sign that the actors in that ecosystem are trying to divide up their labor in worthwhile ways. Therefore, Gradle embraces dependency management.

We will consider the problem of dependency management primarily from a Java perspective, since the Java community has excelled both in creating an enormous dependency management problem, and in solving it effectively. Java’s early embrace of open source caused thousands of software modules to proliferate, and typical projects soon came to depend on dozens of these individual modules. The modules, in turn, depend heavily on one another.

Of course, Java dependency management solutions also apply to related languages of the JVM. Groovy and Scala builds will apply the exact same techniques shown in this chapter.

What Is Dependency Management?

You may have worked with a build that constructed the compile classpath for ...