com.ab.network.toolbox.DiskBasedCache类 参考

类 com.ab.network.toolbox.DiskBasedCache 继承关系图:

类
class	CacheHeader
class	CountingInputStream

Public 成员函数
	DiskBasedCache (File rootDirectory, int maxCacheSizeInBytes)
	DiskBasedCache (File rootDirectory)
synchronized void	clear ()
synchronized Entry	get (String key)
synchronized void	initialize ()
synchronized void	invalidate (String key, boolean fullExpire)
synchronized void	put (String key, Entry entry)
synchronized void	remove (String key)
File	getFileForKey (String key)

静态包函数
static void	writeInt (OutputStream os, int n) throws IOException
static int	readInt (InputStream is) throws IOException
static void	writeLong (OutputStream os, long n) throws IOException
static long	readLong (InputStream is) throws IOException
static void	writeString (OutputStream os, String s) throws IOException
static String	readString (InputStream is) throws IOException
static void	writeStringStringMap (Map< String, String > map, OutputStream os) throws IOException
static Map< String, String >	readStringStringMap (InputStream is) throws IOException

Private 成员函数
String	getFilenameForKey (String key)
void	pruneIfNeeded (int neededSpace)
void	putEntry (String key, CacheHeader entry)
void	removeEntry (String key)

静态 Private 成员函数
static byte[]	streamToBytes (InputStream in, int length) throws IOException
static int	read (InputStream is) throws IOException

Private 属性
final Map< String, CacheHeader >	mEntries
long	mTotalSize = 0
final File	mRootDirectory
final int	mMaxCacheSizeInBytes

静态 Private 属性
static final int	DEFAULT_DISK_USAGE_BYTES = 5 * 1024 * 1024
static final float	HYSTERESIS_FACTOR = 0.9f
static final int	CACHE_MAGIC = 0x20120504

详细描述

Cache implementation that caches files directly onto the hard disk in the specified directory. The default disk usage size is 5MB, but is configurable.

构造及析构函数说明

com.ab.network.toolbox.DiskBasedCache.DiskBasedCache ( File  rootDirectory, int  maxCacheSizeInBytes  )

inline

Constructs an instance of the DiskBasedCache at the specified directory.

参数

rootDirectory	The root directory of the cache.
maxCacheSizeInBytes	The maximum size of the cache in bytes.

com.ab.network.toolbox.DiskBasedCache.DiskBasedCache ( File  rootDirectory )

inline

Constructs an instance of the DiskBasedCache at the specified directory using the default maximum cache size of 5MB.

参数

rootDirectory

The root directory of the cache.

成员函数说明

synchronized void com.ab.network.toolbox.DiskBasedCache.clear ( )

inline

Clears the cache. Deletes all cached files from disk.

实现了 com.ab.network.toolbox.Cache.

synchronized Entry com.ab.network.toolbox.DiskBasedCache.get ( String  key )

inline

Returns the cache entry with the specified key if it exists, null otherwise.

实现了 com.ab.network.toolbox.Cache.

File com.ab.network.toolbox.DiskBasedCache.getFileForKey ( String  key )

inline

Returns a file object for the given cache key.

String com.ab.network.toolbox.DiskBasedCache.getFilenameForKey ( String  key )

inlineprivate

Creates a pseudo-unique filename for the specified cache key.

参数

key	The key to generate a file name for.

返回

A pseudo-unique filename.

synchronized void com.ab.network.toolbox.DiskBasedCache.initialize ( )

inline

Initializes the DiskBasedCache by scanning for all files currently in the specified root directory. Creates the root directory if necessary.

实现了 com.ab.network.toolbox.Cache.

synchronized void com.ab.network.toolbox.DiskBasedCache.invalidate ( String  key, boolean  fullExpire  )

inline

Invalidates an entry in the cache.

参数

key	Cache key
fullExpire	True to fully expire the entry, false to soft expire

实现了 com.ab.network.toolbox.Cache.

void com.ab.network.toolbox.DiskBasedCache.pruneIfNeeded ( int  neededSpace )

inlineprivate

Prunes the cache to fit the amount of bytes specified.

参数

neededSpace

The amount of bytes we are trying to fit into the cache.

synchronized void com.ab.network.toolbox.DiskBasedCache.put ( String  key, Entry  entry  )

inline

Puts the entry with the specified key into the cache.

实现了 com.ab.network.toolbox.Cache.

void com.ab.network.toolbox.DiskBasedCache.putEntry ( String  key, CacheHeader  entry  )

inlineprivate

Puts the entry with the specified key into the cache.

参数

key	The key to identify the entry by.
entry	The entry to cache.

static int com.ab.network.toolbox.DiskBasedCache.read ( InputStream  is ) throws IOException

inlinestaticprivate

Simple wrapper around InputStream#read() that throws EOFException instead of returning -1.

static int com.ab.network.toolbox.DiskBasedCache.readInt ( InputStream  is ) throws IOException

inlinestaticpackage

static long com.ab.network.toolbox.DiskBasedCache.readLong ( InputStream  is ) throws IOException

inlinestaticpackage

static String com.ab.network.toolbox.DiskBasedCache.readString ( InputStream  is ) throws IOException

inlinestaticpackage

static Map<String, String> com.ab.network.toolbox.DiskBasedCache.readStringStringMap ( InputStream  is ) throws IOException

inlinestaticpackage

synchronized void com.ab.network.toolbox.DiskBasedCache.remove ( String  key )

inline

Removes the specified key from the cache if it exists.

实现了 com.ab.network.toolbox.Cache.

void com.ab.network.toolbox.DiskBasedCache.removeEntry ( String  key )

inlineprivate

Removes the entry identified by 'key' from the cache.

static byte [] com.ab.network.toolbox.DiskBasedCache.streamToBytes ( InputStream  in, int  length  ) throws IOException

inlinestaticprivate

Reads the contents of an InputStream into a byte[].

static void com.ab.network.toolbox.DiskBasedCache.writeInt ( OutputStream  os, int  n  ) throws IOException

inlinestaticpackage

static void com.ab.network.toolbox.DiskBasedCache.writeLong ( OutputStream  os, long  n  ) throws IOException

inlinestaticpackage

static void com.ab.network.toolbox.DiskBasedCache.writeString ( OutputStream  os, String  s  ) throws IOException

inlinestaticpackage

static void com.ab.network.toolbox.DiskBasedCache.writeStringStringMap ( Map< String, String >  map, OutputStream  os  ) throws IOException

inlinestaticpackage

类成员变量说明

final int com.ab.network.toolbox.DiskBasedCache.CACHE_MAGIC = 0x20120504

staticprivate

Magic number for current version of cache file format.

final int com.ab.network.toolbox.DiskBasedCache.DEFAULT_DISK_USAGE_BYTES = 5 * 1024 * 1024

staticprivate

Default maximum disk usage in bytes.

final float com.ab.network.toolbox.DiskBasedCache.HYSTERESIS_FACTOR = 0.9f

staticprivate

High water mark percentage for the cache

final Map<String, CacheHeader> com.ab.network.toolbox.DiskBasedCache.mEntries

private

初始值:

=
            new LinkedHashMap<String, CacheHeader>(16, .75f, true)

Map of the Key, CacheHeader pairs

final int com.ab.network.toolbox.DiskBasedCache.mMaxCacheSizeInBytes

private

The maximum size of the cache in bytes.

final File com.ab.network.toolbox.DiskBasedCache.mRootDirectory

private

The root directory to use for the cache.

long com.ab.network.toolbox.DiskBasedCache.mTotalSize = 0

private

Total amount of space currently used by the cache in bytes.

---

该类的文档由以下文件生成:

• src/com/ab/network/toolbox/DiskBasedCache.java