org.protempa.datastore

Class DroolsWorkingMemoryStore

java.lang.Object

org.protempa.datastore.DroolsWorkingMemoryStore

All Implemented Interfaces:

AutoCloseable, Map<String,org.drools.StatefulSession>, org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

public final class DroolsWorkingMemoryStore
extends Object
implements org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

A data store mapping key IDs to Drools working memory objects. This specialized class is necessary because of the way Drools and BerkeleyDB handle object serialization. Drools expects to deserialize its objects in a custom way that BerkeleyDB breaks. The solution is to convert the working memory to a byte array and have BDB serialize that instead. The byte array can then be deserialized into a Drools rule base, which can generate the original working memory.

Author:

Michel Mansour

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
DroolsWorkingMemoryStore(org.eurekaclinical.datastore.DataStoreFactory storeFactory, String dbName, org.drools.RuleBase ruleBase)

Method Summary

Modifier and Type	Method and Description
void	clear()
void	close()
boolean	containsKey(Object key)
boolean	containsValue(Object value)
Set<Map.Entry<String,org.drools.StatefulSession>>	entrySet() Returns a collection view of the map.
org.drools.StatefulSession	get(Object key) Gets a working memory from the data store.
boolean	isClosed()
boolean	isEmpty()
Set<String>	keySet()
org.drools.StatefulSession	put(String key, org.drools.StatefulSession value) Puts the working memory into the data store.
void	putAll(Map<? extends String,? extends org.drools.StatefulSession> m) Writes all of the keyId-working memory pairs in the given map to the data store.
org.drools.StatefulSession	remove(Object key)
int	size()
Collection<org.drools.StatefulSession>	values() Gets the working memories from this data store.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

Constructor Detail

DroolsWorkingMemoryStore

public DroolsWorkingMemoryStore(org.eurekaclinical.datastore.DataStoreFactory storeFactory,
                                String dbName,
                                org.drools.RuleBase ruleBase)
                         throws IOException

Throws:

IOException

Method Detail

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

isClosed

public boolean isClosed()

Specified by:

isClosed in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

get

public org.drools.StatefulSession get(Object key)

Gets a working memory from the data store.

Specified by:

get in interface Map<String,org.drools.StatefulSession>

Specified by:

get in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

Parameters:

key - the keyId.

Returns:

the working memory, or null if the data store contains no working memory for the given keyId.

put

public org.drools.StatefulSession put(String key,
                                      org.drools.StatefulSession value)

Puts the working memory into the data store.

Specified by:

put in interface Map<String,org.drools.StatefulSession>

Specified by:

put in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

Parameters:

key - the keyId.

value - the working memory.

Returns:

the working memory.

Throws:

IOError - if an error occurs writing the key and working memory to the data store.

size

public int size()

Specified by:

size in interface Map<String,org.drools.StatefulSession>

Specified by:

size in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<String,org.drools.StatefulSession>

Specified by:

isEmpty in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

containsKey

public boolean containsKey(Object key)

Specified by:

containsKey in interface Map<String,org.drools.StatefulSession>

Specified by:

containsKey in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

containsValue

public boolean containsValue(Object value)

Specified by:

containsValue in interface Map<String,org.drools.StatefulSession>

Specified by:

containsValue in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

remove

public org.drools.StatefulSession remove(Object key)

Specified by:

remove in interface Map<String,org.drools.StatefulSession>

Specified by:

remove in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

putAll

public void putAll(Map<? extends String,? extends org.drools.StatefulSession> m)

Writes all of the keyId-working memory pairs in the given map to the data store.

Specified by:

putAll in interface Map<String,org.drools.StatefulSession>

Specified by:

putAll in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

Parameters:

m - a map of keyId-working memory pairs.

Throws:

IOError - if an error occurs writing a working memory to the data store.

clear

public void clear()

Specified by:

clear in interface Map<String,org.drools.StatefulSession>

Specified by:

clear in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

keySet

public Set<String> keySet()

Specified by:

keySet in interface Map<String,org.drools.StatefulSession>

Specified by:

keySet in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

values

public Collection<org.drools.StatefulSession> values()

Gets the working memories from this data store. Depending on how many working memories that have been saved, this operation could exhaust memory!

Specified by:

values in interface Map<String,org.drools.StatefulSession>

Specified by:

values in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

Returns:

a collection of working memories.

Throws:

IOError - if an error occurred while reading the working memories.

entrySet

public Set<Map.Entry<String,org.drools.StatefulSession>> entrySet()

Returns a collection view of the map. It reads the working memories lazily. Each call to Map.Entry#getValue() could throw an IOError if an error occurs while reading the entry's working memory from the data store.

Specified by:

entrySet in interface Map<String,org.drools.StatefulSession>

Specified by:

entrySet in interface org.eurekaclinical.datastore.DataStore<String,org.drools.StatefulSession>

Returns:

a collection view of the map.