When projects get so big that no one person can visualize the whole thing, some times tools that can visualize the architecture and measure it's complexity are needed. Headway Software just released version 2 of Structure101, "an interactive tool that shows you dependency graphs from your code-base. It lets you see these as either diagrams (the familiar Directed Graph) or dependency matrices." said Structure101 CTO Chris Chedgey, talking to InfoQ.According to Chris, for any dependency:
you can discover which code-level references (like class extends class or method calls method) causes higher level dependencies (like package depends on package or jar depends on jar). After that, Structure101 is about helping you find structurally significant dependency graphs. For example it takes you straight to "tangles" (cyclic dependencies) at any level of composition (class, design, jar) and in any hierarchy (e.g. jar or package).Structure101 also includes a measurement framework that lets you drill down on the size and complexity in your code-base and prioritize problems in terms of how much they are likely costing you in terms of developer productivity. Structure101 also includes a repository and web application that let you compare the size and complexity of all your projects, track how metrics are changing over time and see exactly how the design or architecture changed between any two builds.
Version 2 adds:
Structure 101 is being used by a number of large organizations, including Expedia, European commission, Credit Suisse, Delta airlines, the US Airforce and Navy, and others; it is primarily being used in two ways:
- A new Slice perspective that lets you see your whole code-base at any level of composition, for example at the class level, package level or at any design level.
- A dependency structure matrix ('dsm') representation for large dependency graphs (such as slices).
- Tagging of code-level items in order to discover how they roll up through different slices and hierarchies.
- Hiding of model items.
The first is to understand and control the complexity of their code-base. The second is to understand and control their architecture. For the former, they are looking to understand the structure of their code, where it is complex and how to go about refactoring or restructuring it in order to maximize ongoing development productivity (what the XP guys call "agility"). For the latter, they are using the "transformation" capability in order to create their "architectural" view, and then monitoring any structural changes (using the snapshot "comparison" capability) with each build in order to control the evolution of the architecture.The majority of their customers are working with codebases in the 25-75k lines of code range, "but on the other hand the cost of complexity is really proportional to the number of developers" said Chris. Headway was established late 99. "We have found that the awareness of software structure and the importance of controlling its complexity to be growing enormously over the last 2 years."