Added more generic Mac Framework support

[shanewholloway]

A few minor changes to allow loading of Mac Frameworks outside of /System/Library/Frameworks using standard DYLD fallback paths and any addSearchPath() supplied entries.

[twall]

why the trailing slash?

[shanewholloway]

It seemed more consistent with other tests in the file, since they could all be tested with beginsWith() and endsWith(). Using a leading dot and trailing slash bounded the test on both ends. And it fits the definition of a Mac Framework: a bundle directory structure with a .framework for the directory name. Thus the test includes that the libraryName acknowledges it as a directory.

[twall]

I'm just thinking that I'd say "JavaVM.framework" to indicate the library I want, I wouldn't explicitly add a trailing slash.

[twall]

Perhaps a use case to indicate how you'd actually use this (a test case could reasonably "install" something in ~/LibraryFrameworks and subsequently attempt to load it)?

[shanewholloway]

I was taking a minimal change approach to modifying the code to support loading general frameworks. There are three ways a framework can be specified — MyKit.framework/MyKit, MyKit.framework/Versions/Current/MyKit, or MyKit.framework/Versions/YYY/MyKit. This was the smallest change I could come up with that could address all three cases and leave the user in control.

The changes I submitted are enough to enable generic loading of a framework from /Library/Frameworks or from ~/Library/Frameworks, where before an absolute path to the framework binary was required to bypass all the checks — So the change is an strict improvement, but there is certainly room for more.

The macholib of Python approaches this problem by returning a list of alternatives from the parallel to mapLibraryName() so that many different options can be used, and the loadLibrary could remain "MyKit" instead of "MyKit.framework".

Another option could be:

if (libName.contains(".framework")) {
    if (libName.endsWith(".framework")) {
       // get <name> before ".framework", and construct a result like "<name>.framework/Versions/Current/<name>"
    } else return libName;
}

This is quite literally the first Java code I've ever written, so complex string work in Java is a bit beyond my skills of mimicry.

[twall]

I think you could change the code circa line 152 to loop over the extra frameworks paths (instead of trying a single one), and expand the extra paths to include potential name variations, e.g.
suffix = name.indexOf(".framework") == -1 ? name + ".framework/" + name : name;
for each:
"~/Library/Frameworks/" + name,
"/Library/Frameworks/" + name,
"/System/Library/Frameworks/" + name;
try library lookup and break when found

This allows specification by framework name, or explicit framework path to a particular version.

[twall]

Applied changes to look up additional paths, as wall as allowing a versioned framework path.