README.txt revision b03c8c508dcbbef364e624ad5bc0ab6fa6733dc7
1This library (com.android.location.provider.jar) is a shared java library
2containing classes required by unbundled location providers.
3
4--- Rules of this library ---
5o This library is effectively a PUBLIC API for unbundled location providers
6  that may be distributed outside the system image. So it MUST BE API STABLE.
7  You can add but not remove. The rules are the same as for the
8  public platform SDK API.
9o This library can see and instantiate internal platform classes (such as
10  ProviderRequest.java), but it must not expose them in any public method
11  (or by extending them via inheritance). This would break clients of the
12  library because they cannot see the internal platform classes.
13
14This library is distributed in the system image, and loaded as
15a shared library. So you can change the implementation, but not
16the interface. In this way it is like framework.jar.
17
18--- Why does this library exists? ---
19
20Unbundled location providers (such as the NetworkLocationProvider)
21can not use internal platform classes.
22
23So ideally all of these classes would be part of the public platform SDK API,
24but that doesn't seem like a great idea when only applications with a special
25signature can implement this API.
26
27The compromise is this library.
28
29It wraps internal platform classes (like ProviderRequest) with a stable
30API that does not leak the internal classes.
31