java.net
public
abstract
class
java.net.ResponseCache
ResponseCache implements URLConnection caches. System default cache can be
registered by invoking ResponseCache.setDefault
(ResponseCache),
and can be retrieved by invoking ResponseCache.getDefault
.
If URLConnection#useCaches is set, URLConnection
class will
use ResponseCache
to store and get resources. Whether the
resource is cached depends on ResponseCache
implementation. If
a request resource is cached, protocol handler will fecth it from the cache.
If the protocol handler fails to get resource from the cache, it turns to get
the resource from its original location.
Summary
Public Constructors
Public Methods
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
Details
Public Constructors
public
ResponseCache()
Constructor method.
Public Methods
Gets the cached response according to requesting uri,method and headers.
Parameters
uri
| A URL represents requesting uri. |
rqstMethod
| A String represents requesting method. |
rqstHeaders
| A Map from request header field names to lists
of field values represents requesting headers. |
Returns
- A
CacheResponse
object if the request is available
in the cache. Otherwise, this method returns null.
public
static
ResponseCache
getDefault()
Gets system default response cache.
Throws
SecurityException
| If a security manager is installed and it doesn't have
NetPermission ("getResponseCache").
|
Protocol handler calls this method after retrieving resources. The
ResponseCache
decides whether the resource should be
cached. If the resource needs to be cached, this method will return a
CacheRequest
with a
WriteableByteChannel
,
and then, protocol handler will use this channel to write the resource
data into the cache. Otherwise, if the resource doesn't need to be
cached, it returns null.
Returns
- a
CacheRequest
which contains
WriteableByteChannel
if the resource is cached.
Otherwise, it returns null.
public
static
void
setDefault(ResponseCache responseCache)
Sets the system default response cache when responseCache is not null.
Otherwise, the method unsets the system default response cache. This
setting may be ignored by some non-standard protocols.
Parameters
responseCache
| Set default ResponseCache . If responseCache is
null, it unsets the cache. |
Throws
SecurityException
| If a security manager is installed and it doesn't have
NetPermission ("setResponseCache").
|