Package org.yamcs.parameter
Class ParameterCacheImpl
- java.lang.Object
-
- org.yamcs.parameter.ParameterCacheImpl
-
- All Implemented Interfaces:
ParameterCache
public class ParameterCacheImpl extends Object implements ParameterCache
Used by theParameterRequestManagerto cache last values of parameters. The cache will contain the parameters for a predefined time period but can exceed that period if space is available in the CacheEntry. A CacheEntry also has a maximum size to prevent it accumulating parameters ad infinitum (e.g. if there are bogus parameters with the timestamp never changing) We keep delivery consisting of lists of parameter values together such that if two parameters have been acquired in the same delivery, they will be given from the same delivery to the clients. if cacheAll is enabled, all parameters will be cached as they are received. if cacheAll is disabled: - a parameter will be put on the list to cache only if somebody has requested it. - obviously first time when the parameter is requested, no value will be returned. - however this will greatly reduce the cache size since only a few parameters are monitored in the displays
-
-
Constructor Summary
Constructors Constructor Description ParameterCacheImpl(ParameterCacheConfig cacheConfig)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description voidclear()Remove all the parameters from the cacheList<ParameterValue>getAllValues(Parameter p)Returns all values from the cache for the parameter or null if there is no value cached The parameter are returned in descending order (newest parameter is returned first)List<ParameterValue>getAllValues(Parameter p, long start, long stop)Same as above but return all values that have the generation time in the (start, stop] intervalParameterValuegetLastValue(Parameter p)Returns last cached value for parameter or null if there is no value in the cacheList<ParameterValue>getValues(List<Parameter> plist)Returns cached value for parameter or an empty list if there is no value in the cachevoidupdate(Collection<ParameterValue> pvs)update the parameters in the cache
-
-
-
Constructor Detail
-
ParameterCacheImpl
public ParameterCacheImpl(ParameterCacheConfig cacheConfig)
-
-
Method Detail
-
update
public void update(Collection<ParameterValue> pvs)
Description copied from interface:ParameterCacheupdate the parameters in the cache- Specified by:
updatein interfaceParameterCache- Parameters:
pvs- - parameter value list
-
getValues
public List<ParameterValue> getValues(List<Parameter> plist)
Description copied from interface:ParameterCacheReturns cached value for parameter or an empty list if there is no value in the cache- Specified by:
getValuesin interfaceParameterCache- Returns:
-
getLastValue
public ParameterValue getLastValue(Parameter p)
Description copied from interface:ParameterCacheReturns last cached value for parameter or null if there is no value in the cache- Specified by:
getLastValuein interfaceParameterCache- Parameters:
p- - parameter for which the last value is returned- Returns:
-
getAllValues
public List<ParameterValue> getAllValues(Parameter p)
Description copied from interface:ParameterCacheReturns all values from the cache for the parameter or null if there is no value cached The parameter are returned in descending order (newest parameter is returned first)- Specified by:
getAllValuesin interfaceParameterCache- Parameters:
p- - parameter for which all values are returned- Returns:
- all values from the cache for the parameter or null if there is no value cached
-
getAllValues
public List<ParameterValue> getAllValues(Parameter p, long start, long stop)
Description copied from interface:ParameterCacheSame as above but return all values that have the generation time in the (start, stop] interval- Specified by:
getAllValuesin interfaceParameterCache- Returns:
-
clear
public void clear()
Description copied from interface:ParameterCacheRemove all the parameters from the cache- Specified by:
clearin interfaceParameterCache
-
-