30 July 2019
How to run exec-maven-plugin only if a file is not up-to-date
In my Maven build, I use exec-maven-plugin to run an external tool for Java code generation. In this case the flatbuffers compiler (flatc).
By default, flatc always runs, so you always get a new .java file. This will always trigger Java compiler to run, which will in turn always trigger jar packaging to run, etc. I would like flatc to only run if it’s source file is updated, so I can get a properly incremental build and avoid needlessly recompiling.
10 February 2016
Data structures and Domain Driven Design
After listening to a presentation about Domain Driven Security, I got some additional insights about what a data structure (as opposed to OOP object) should be able to do. Data structures (I call them struct) should have a subset of OOP features which I think is useful and harmless.
A struct should allow constructors. Such constructors can have two purposes, to convert one type of data into another and to validate the input.
8 February 2016
Objects vs. data structures
Several popular statically typed programming languages, including C++, Java and C#, have a serious design flaw. They make no useful distinction between objects in the OOP sense and plain data structures.
A plain data structure should only be a dumb container for data. It should not have any behaviour, only simple accessors for data items in it. It should not be possible to override data accessors. It should be clear and transparent what it does.