com.hannesdorfmann.httpkit.cache

Class HybridCache<K,V>

java.lang.Object

com.hannesdorfmann.httpkit.cache.HybridCache<K,V>

All Implemented Interfaces:

Cache<K,V>

public class HybridCache<K,V>
extends Object
implements Cache<K,V>

This is a hybrid cache that uses a memory cache (RAM) and a disk cache (external storage) to cache any data

Author:

Hannes Dorfmann

Constructor Summary

Constructors

Constructor and Description
HybridCache()

Method Summary

Methods

Modifier and Type	Method and Description
void	addDiskCache(DiskCache<K,V> cache) Add a disk cache
void	addMemoryCache(MemoryCache<K,V> cache) Adds a memory cache
void	clear() Cleans the cache, by removing all cache entries
CacheEntry<V>	getFromDiskCache(K key, Class<?> targetClass, int collectionType) Get a value from the cache by passing additional information for the ParserWriter
CacheEntry<V>	getFromMemoryCache(K key) Do a quick look up.
ParserWriterPool	getParserWriterPool() Get the ParserWriterPool.
void	onLowMemory() This method is called, when the memory of the device runs low (RAM).
void	putRawToDiskCache(K key, byte[] value, String mimeType, String charsetEncoding, Long expirationTimeStamp, String eTag) Write as raw bytes
void	putToDiskCache(K key, V value, String mimeType, String charsetEncoding, Long expirationTimeStamp, String eTag) Write
void	putToMemoryCache(K key, CacheEntry<V> entry) Put a already existing CacheEntry to the memory cache.
void	putToMemoryCache(K key, V value, String mimeType, String charsetEncoding, Long expirationTimeStamp, String eTag) Adds and create a new CacheEntry to the cache.
void	remove(K key) Removes the Entry
void	removeDiskCache(DiskCache<K,V> cache) remove a Disk cache
void	removeMemoryCache(MemoryCache<K,V> cache) remove a memory cache
void	updateExpirationTimestamp(K key, long expirationTimestamp) Updates the cached entries expiration timestamp (identified by the key)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HybridCache

public HybridCache()

Method Detail

getFromDiskCache

public CacheEntry<V> getFromDiskCache(K key,
                             Class<?> targetClass,
                             int collectionType)
                               throws Exception

Description copied from interface: Cache

Get a value from the cache by passing additional information for the ParserWriter

Specified by:

getFromDiskCache in interface Cache<K,V>

Parameters:

key - The key

targetClass - The target class, to where the retrieved entry should be mapped (with an objectmapper)

collectionType - The returning collection type, like List, etc. This must be one of the constatns specified int ParserWriter.COLLECTION_TYPE_NONE, ParserWriter.COLLECTION_TYPE_LIST, etc. ...

Returns:

Throws:

Exception

remove

public void remove(K key)
            throws IOException

Description copied from interface: Cache

Removes the Entry

Specified by:

remove in interface Cache<K,V>

Throws:

IOException

getParserWriterPool

public ParserWriterPool getParserWriterPool()

Description copied from interface: Cache

Get the ParserWriterPool. Add in there any ParserWriter your cache should be able to handle and parse

Specified by:

getParserWriterPool in interface Cache<K,V>

onLowMemory

public void onLowMemory()

Description copied from interface: Cache

This method is called, when the memory of the device runs low (RAM).

Specified by:

onLowMemory in interface Cache<K,V>

clear

public void clear()
           throws IOException

Description copied from interface: Cache

Cleans the cache, by removing all cache entries

Specified by:

clear in interface Cache<K,V>

Throws:

IOException

getFromMemoryCache

public CacheEntry<V> getFromMemoryCache(K key)

Description copied from interface: Cache

Do a quick look up. Quick means, that no long running action like loading a resource file or something from the disk cache is done with this method call. So this one is used for memory cache lookups.

Specified by:

getFromMemoryCache in interface Cache<K,V>

Parameters:

key - The key

Returns:

The value you try to find, or null if not found quickly and a longer resource loading must be done

addMemoryCache

public void addMemoryCache(MemoryCache<K,V> cache)

Description copied from interface: Cache

Adds a memory cache

Specified by:

addMemoryCache in interface Cache<K,V>

removeMemoryCache

public void removeMemoryCache(MemoryCache<K,V> cache)

Description copied from interface: Cache

remove a memory cache

Specified by:

removeMemoryCache in interface Cache<K,V>

addDiskCache

public void addDiskCache(DiskCache<K,V> cache)

Description copied from interface: Cache

Add a disk cache

Specified by:

addDiskCache in interface Cache<K,V>

removeDiskCache

public void removeDiskCache(DiskCache<K,V> cache)

Description copied from interface: Cache

remove a Disk cache

Specified by:

removeDiskCache in interface Cache<K,V>

putToMemoryCache

public void putToMemoryCache(K key,
                    V value,
                    String mimeType,
                    String charsetEncoding,
                    Long expirationTimeStamp,
                    String eTag)

Description copied from interface: Cache

Adds and create a new CacheEntry to the cache.

Specified by:

putToMemoryCache in interface Cache<K,V>

Parameters:

key - The key

value - The Value for the given key

mimeType - The mime type of the value. This is important to find the correct parser for the stored cache value

charsetEncoding - The charset like, UTF-8 etc. that is used, to encode the string content (is useless for binary data)

expirationTimeStamp - The expiration value

eTag - The ETag

putToMemoryCache

public void putToMemoryCache(K key,
                    CacheEntry<V> entry)

Description copied from interface: Cache

Put a already existing CacheEntry to the memory cache. This will normally be called if you want to put a entry retrieved from disc cache to the meme

Specified by:

putToMemoryCache in interface Cache<K,V>

putToDiskCache

public void putToDiskCache(K key,
                  V value,
                  String mimeType,
                  String charsetEncoding,
                  Long expirationTimeStamp,
                  String eTag)
                    throws Exception

Description copied from interface: Cache

Write

Specified by:

putToDiskCache in interface Cache<K,V>

Throws:

Exception

putRawToDiskCache

public void putRawToDiskCache(K key,
                     byte[] value,
                     String mimeType,
                     String charsetEncoding,
                     Long expirationTimeStamp,
                     String eTag)
                       throws Exception

Description copied from interface: Cache

Write as raw bytes

Specified by:

putRawToDiskCache in interface Cache<K,V>

Throws:

Exception

updateExpirationTimestamp

public void updateExpirationTimestamp(K key,
                             long expirationTimestamp)
                               throws IOException

Description copied from interface: Cache

Updates the cached entries expiration timestamp (identified by the key)

Specified by:

updateExpirationTimestamp in interface Cache<K,V>

Throws:

IOException