com.android.volley.toolbox
Class DiskBasedCache

java.lang.Object
  com.android.volley.toolbox.DiskBasedCache

All Implemented Interfaces:

Cache

public class DiskBasedCache
extends Object
implements Cache

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

Nested Class Summary

(package private) static class

DiskBasedCache.CacheHeader Handles holding onto the cache headers for an entry.

Nested classes/interfaces inherited from interface com.android.volley.Cache

Cache.Entry

Constructor Summary

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

DiskBasedCache(File rootDirectory, int maxCacheSizeInBytes)
Constructs an instance of the DiskBasedCache at the specified directory.

Method Summary

void	clear() Clears the cache.
Cache.Entry	get(String key) Returns the cache entry with the specified key if it exists, null otherwise.
File	getFileForKey(String key) Returns a file object for the given cache key.
void	initialize() Initializes the DiskBasedCache by scanning for all files currently in the specified root directory.
void	invalidate(String key, boolean fullExpire) Invalidates an entry in the cache.
void	put(String key, Cache.Entry entry) Puts the entry with the specified key into the cache.
(package private) static int	readInt(InputStream is)
(package private) static long	readLong(InputStream is)
(package private) static String	readString(InputStream is)
(package private) static Map<String,String>	readStringStringMap(InputStream is)
void	remove(String key) Removes the specified key from the cache if it exists.
(package private) static void	writeInt(OutputStream os, int n)
(package private) static void	writeLong(OutputStream os, long n)
(package private) static void	writeString(OutputStream os, String s)
(package private) static void	writeStringStringMap(Map<String,String> map, OutputStream os)

Methods inherited from class java.lang.Object

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

Constructor Detail

DiskBasedCache

public DiskBasedCache(File rootDirectory,
                      int maxCacheSizeInBytes)

Constructs an instance of the DiskBasedCache at the specified directory.

Parameters:

rootDirectory - The root directory of the cache.

maxCacheSizeInBytes - The maximum size of the cache in bytes.

DiskBasedCache

public DiskBasedCache(File rootDirectory)

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

Parameters:

rootDirectory - The root directory of the cache.

Method Detail

clear

public void clear()

Clears the cache. Deletes all cached files from disk.

Specified by:

clear in interface Cache

get

public Cache.Entry get(String key)

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

Specified by:

get in interface Cache

Parameters:

key - Cache key

Returns:

An Cache.Entry or null in the event of a cache miss

initialize

public void initialize()

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

Specified by:

initialize in interface Cache

invalidate

public void invalidate(String key,
                       boolean fullExpire)

Invalidates an entry in the cache.

Specified by:

invalidate in interface Cache

Parameters:

key - Cache key

fullExpire - True to fully expire the entry, false to soft expire

put

public void put(String key,
                Cache.Entry entry)

Puts the entry with the specified key into the cache.

Specified by:

put in interface Cache

Parameters:

key - Cache key

entry - Data to store and metadata for cache coherency, TTL, etc.

remove

public void remove(String key)

Removes the specified key from the cache if it exists.

Specified by:

remove in interface Cache

Parameters:

key - Cache key

getFileForKey

public File getFileForKey(String key)

Returns a file object for the given cache key.

writeInt

static void writeInt(OutputStream os,
                     int n)
              throws IOException

Throws:

IOException

readInt

static int readInt(InputStream is)
            throws IOException

Throws:

IOException

writeLong

static void writeLong(OutputStream os,
                      long n)
               throws IOException

Throws:

IOException

readLong

static long readLong(InputStream is)
              throws IOException

Throws:

IOException

writeString

static void writeString(OutputStream os,
                        String s)
                 throws IOException

Throws:

IOException

readString

static String readString(InputStream is)
                  throws IOException

Throws:

IOException

writeStringStringMap

static void writeStringStringMap(Map<String,String> map,
                                 OutputStream os)
                          throws IOException

Throws:

IOException

readStringStringMap

static Map<String,String> readStringStringMap(InputStream is)
                                       throws IOException

Throws:

IOException