My package builds, as usual, upon several external packages. I want to modify one of the externals, so I go grab its open source. It is in turn built upon further externals, so I get jars for those until all but one dependency is fulfilled: org.codehaus.jackson.JsonParser, called out of the jackson-mapper jar. I take a guess that JsonParser is in the jackson-core.jar (how do you know?) so I add it. My dependency is resolved, and different dependencies suddenly appear for 6 of the source files that previously looked complete. One step forward, 6 steps back. (All this in Eclipse) What am I missing? Maybe not all dependencies are found in one pass? How do you find and resolve dependencies?
Thanks!
You need to outline how you are doing dependencies. From your description it sounds like you are manually working out what is needed, downloading the jars and installing them into your project. This is perhaps the most complicated, slowest and most painful way of doing things.
I would suggest that you look into using the Ivy dependency manager (usually used with the Ant build tool, or the Maven build tool which has an inbuilt dependency manager. A further and more advanced tool (IMHO) is Gradle which uses Ivy behind the scenes and can easily be told to use both Ivy and Maven repositories to source jars from.
The advantage of using these tools is that they take care of the dirty work of figuring out the dependencies and downloading the files. They are not a complete solution and you will still have to work out version conflicts and other issues, but they take most of the pain out.