I'm interested in object orientation from the perspective that an object is a process and it has behaviours with other objects and internal mechanisms. Similar

I'm interested in object orientation from the perspective that an object is a process and it has behaviours with other objects and internal mechanisms. Similar to message passing. Unfortunately I rarely see interaction diagrams of compositional nature of objects, so it's not obvious how most software is meant to work without an example sample. Am I alone that Javadocs or Doxygen docs are not enough to understand an object orientated product? I think referring to "local understanding" of objects is a really good point. The more you can understand locally, the more you can actively include in your thinking.