net.handle.hdllib

Class MemCache

java.lang.Object

net.handle.hdllib.MemCache

All Implemented Interfaces:

Cache

public class MemCache
extends java.lang.Object
implements Cache

Class used to cache values in a local database file.

Constructor Summary

Constructors

Constructor and Description
MemCache()
MemCache(int maxHandles, long maxTTL)
MemCache(int maxHandles, long maxTTL, boolean trackHits)
MemCache(long maxTTL)

Method Summary

Modifier and Type	Method and Description
void	clear() Remove all values from the cache
void	close()
byte[][]	getCachedValues(byte[] handle, byte[][] reqTypes, int[] reqIndexes) Returns any non-expired handle values that are in the caches storage.
boolean	isCachedNotFound(byte[][] values) Returns true if this return value of getCachedValues indicates a cached value of HANDLE_NOT_FOUND
void	removeHandle(byte[] handle) Remove one handle from the cache
void	setCachedNotFound(byte[] handle, int ttl) Returns true if this handle should have a cached HANDLE_NOT_FOUND.
void	setCachedValues(byte[] handle, HandleValue[] newValues, byte[][] newTypeList, int[] newIndexList) Store the given handle values after a query for the handle.
void	setMaximumHandles(int maxHandles) Set the maximum size for the cache by the number of handles.
void	setMaximumSize(int maxSize) Set the maximum size for the cache by the number of bytes used for storage.

Methods inherited from class java.lang.Object

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

Constructor Detail

MemCache

public MemCache(int maxHandles,
                long maxTTL)

MemCache

public MemCache(int maxHandles,
                long maxTTL,
                boolean trackHits)

MemCache

public MemCache(long maxTTL)

MemCache

public MemCache()

Method Detail

isCachedNotFound

public boolean isCachedNotFound(byte[][] values)

Description copied from interface: Cache

Returns true if this return value of getCachedValues indicates a cached value of HANDLE_NOT_FOUND

Specified by:

isCachedNotFound in interface Cache

getCachedValues

public byte[][] getCachedValues(byte[] handle,
                                byte[][] reqTypes,
                                int[] reqIndexes)
                         throws java.lang.Exception

Returns any non-expired handle values that are in the caches storage. A null return value indicates that the requested values aren't in the cache. Returning the an array of values (including an array of zero length) indicates that the returned values are the only values from the requested set (ie the handle doesn't have any more values from the requested set). ***** Speed is important in this method *****

Specified by:

getCachedValues in interface Cache

Throws:

java.lang.Exception

setCachedNotFound

public void setCachedNotFound(byte[] handle,
                              int ttl)
                       throws java.lang.Exception

Description copied from interface: Cache

Returns true if this handle should have a cached HANDLE_NOT_FOUND. Pass time-to-live.

Specified by:

setCachedNotFound in interface Cache

Throws:

java.lang.Exception

removeHandle

public void removeHandle(byte[] handle)
                  throws java.lang.Exception

Description copied from interface: Cache

Remove one handle from the cache

Specified by:

removeHandle in interface Cache

Throws:

java.lang.Exception

setCachedValues

public void setCachedValues(byte[] handle,
                            HandleValue[] newValues,
                            byte[][] newTypeList,
                            int[] newIndexList)
                     throws java.lang.Exception

Store the given handle values after a query for the handle. The query was performed with the given type-list and index-list. ***** Speed is less important in this method *****

Specified by:

setCachedValues in interface Cache

Throws:

java.lang.Exception

clear

public void clear()
           throws java.lang.Exception

Remove all values from the cache

Specified by:

clear in interface Cache

Throws:

java.lang.Exception

setMaximumHandles

public void setMaximumHandles(int maxHandles)

Set the maximum size for the cache by the number of handles.

Specified by:

setMaximumHandles in interface Cache

setMaximumSize

public void setMaximumSize(int maxSize)

Set the maximum size for the cache by the number of bytes used for storage.

Specified by:

setMaximumSize in interface Cache

close

public void close()

Specified by:

close in interface Cache