Understanding symbolic links to Android library projects in Eclipse/ADT

When referencing a library project with the current version of the ADT, an Eclipse linkedResource will be created in the .project file. I have a few questions about this.

1. Why an Eclipse link at all? Why not simply add the src/ folder of the library directly using a relative path? You have to set a relative path to it in default.properties anyway, for aapt to see its resource files.
2. This is more an Eclipse question, but I couldn't find an answer to this. The link that will be created has type 2. What does that mean? Which types are there?
3. The link does not use the location attribute, but locationURI, having this format: _android_<lib_name>_5deb8a74/src/main/java What is that, and where does it point? Does the 5deb8a74 part carry any special meaning, or is it just a random string generated to avoid name clashes?

UPDATE I found the documentation on link definition syntax:

link - the definition of a single linked resource.

name - the project-relative path of the linked resource as it appears in the workspace.

type - the resource type. Value values are: "1" for a file, or "2" for a folder.

location - the local file system path of the target of the linked resource. Either an absolute path, or a relative path whose first开发者_StackOverflow社区 segment is the name of a workspace path variable.

locationURI - if the file is not in the local file system, this attribute contains the absolute URI of the resource in some backing file system.

Still not sure why the ADT would use a locationURI, and I still haven't found where these URIs are defined (i.e. where they point to).