public
interface
FileCache
implements DiskTrimmable| com.facebook.cache.disk.FileCache |
 Known Indirect Subclasses
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Class Overview
Interface that caches based on disk should implement.
Summary
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| abstract void | clearAll() | ||||||||||
| abstract long |
clearOldEntries(long cacheExpirationMs)
Deletes old cache files.
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| abstract long | getCount() | ||||||||||
| abstract DiskStorage.DiskDumpInfo | getDumpInfo() | ||||||||||
| abstract BinaryResource |
getResource(CacheKey key)
Returns the binary resource cached with key.
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| abstract long | getSize() | ||||||||||
| abstract boolean | hasKey(CacheKey key) | ||||||||||
| abstract boolean |
hasKeySync(CacheKey key)
Returns true if the key is in the in-memory key index.
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| abstract BinaryResource |
insert(CacheKey key, WriterCallback writer)
Inserts resource into file with key
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| abstract boolean |
isEnabled()
Tells if this cache is enabled.
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| abstract boolean | probe(CacheKey key) | ||||||||||
| abstract void |
remove(CacheKey key)
Removes a resource by key from cache.
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[Expand]
Inherited Methods | |||||||||||
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From interface
com.facebook.common.disk.DiskTrimmable
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Public Methods
public abstract void clearAll ()
public abstract long clearOldEntries (long cacheExpirationMs)
Deletes old cache files.
Parameters
| cacheExpirationMs | files older than this will be deleted. |
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Returns
- the age in ms of the oldest file remaining in the cache.
public abstract long getCount ()
Returns
- the count of pictures in the cache
public abstract BinaryResource getResource (CacheKey key)
Returns the binary resource cached with key.
public abstract long getSize ()
Returns
- the in-use size of the cache
public abstract boolean hasKeySync (CacheKey key)
Returns true if the key is in the in-memory key index.
Not guaranteed to be correct. The cache may yet have this key even if this returns false. But if it returns true, it definitely has it.
Avoids a disk read.
public abstract BinaryResource insert (CacheKey key, WriterCallback writer)
Inserts resource into file with key
Parameters
| key | cache key |
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| writer | Callback that writes to an output stream |
Returns
- a sequence of bytes
Throws
| IOException |
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public abstract boolean isEnabled ()
Tells if this cache is enabled. It's important for some caches that can be disabled without further notice (like in removable/unmountable storage). Anyway a disabled cache should just ignore calls, not fail.
Returns
- true if this cache is usable, false otherwise.
public abstract void remove (CacheKey key)
Removes a resource by key from cache.
Parameters
| key | cache key |
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