Looking for a simple open source non-copyleft caching for Android (SDK 7+) class.
The purpose is primary to store the Bitmaps fetched asynchronously (so
Ignition is what are you looking for: https://github.com/kaeppler/ignition. It allows you to cache images, serialized objects. For cashing part, work with ignition-support
Here's the API for ignition support: http://kaeppler.github.com/ignition-docs/ignition-support/apidocs/.
The plain LruCache suggested above is an in memory cache. From your question it sounds like you are looking for a disk cache solution.
Read the Disk Cache of the Caching Bitmaps android training doc.
Then take a look at the DiskLruCache implementation discussed on the following thread : Using DiskLruCache in android 4.0 does not provide for openCache method
You can grab the DiskLruCache source on GitHub.
How about android.util.LruCache? If you need to support older platforms, simply copy it in you project. EDIT: it's actually in the compat/support library.
You can create your own image cache following this official android documentation that not only gives you the code, but also explains how it works:
http://developer.android.com/training/displaying-bitmaps/cache-bitmap.html
They also explain the whole process, from loading bitmaps, processing them in a background thread, caching them and displaying them
http://developer.android.com/training/displaying-bitmaps/index.html
ICSDiskLruCache.java. This is a port of the DiskLruCache available in ICS and later versions of Android, open-sourced by Google as part of the IO 2012 Android App so it works with versions down to (at least) API level 7.
Find the source at http://code.google.com/p/iosched/source/browse/android/src/com/google/android/apps/iosched/util/ICSDiskLruCache.java
http://docs.guava-libraries.googlecode.com/git-history/v12.0/javadoc/com/google/common/cache/package-summary.html