org.arl.fjage.persistence

Class Store

java.lang.Object

org.arl.fjage.persistence.Store

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class Store
extends java.lang.Object
implements java.io.Closeable

Persistent storage API. The default store is in the user's home directory under a folder called ".fjstore", but may be changed using the setRoot(java.io.File) method.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String	clazz
protected java.lang.ClassLoader	clazzLoader
protected static java.lang.ClassLoader	defaultClazzLoader
protected static java.util.Map<java.lang.String,Store>	instances
protected java.io.File	root
protected static java.io.File	storeRoot

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Store(java.lang.String clazz)

Method Summary

Modifier and Type	Method and Description
void	close() Closes the store.
protected static void	closeQuietly(java.io.InputStream is) Closes input stream quietly.
protected static void	closeQuietly(java.io.OutputStream os) Closes output stream quietly.
boolean	delete() Deletes the data store.
<T> T	getById(java.lang.Class<T> type, java.lang.String id) Gets an object in the store.
<T> java.util.List<T>	getByType(java.lang.Class<T> type) Gets all objects of a given class in the store.
protected java.lang.String	getId(java.io.Serializable obj) Gets the ID for an object.
static Store	getInstance(Agent agent) Gets a store instance for an agent.
protected <T> T	load(java.lang.Class<T> type, java.io.File f) Loads a stored object from a file.
void	put(java.io.Serializable obj) Stores an object.
boolean	remove(java.io.Serializable obj) Removes an object from the store.
<T> boolean	removeById(java.lang.Class<T> type, java.lang.String id) Removes an object from the store.
<T> boolean	removeByType(java.lang.Class<T> type) Removes all objects of a given type from the store.
static void	setClassLoader(java.lang.ClassLoader cl) Sets class loader to use for loading stored classes.
static void	setRoot(java.io.File folder) Sets root folder for store data.
long	size() Gets the size of the data store (in bytes).

Methods inherited from class java.lang.Object

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

Field Detail

storeRoot

protected static java.io.File storeRoot

defaultClazzLoader

protected static java.lang.ClassLoader defaultClazzLoader

instances

protected static java.util.Map<java.lang.String,Store> instances

root

protected java.io.File root

clazz

protected java.lang.String clazz

clazzLoader

protected java.lang.ClassLoader clazzLoader

Constructor Detail

Store

protected Store(java.lang.String clazz)

Method Detail

setRoot

public static void setRoot(java.io.File folder)

Sets root folder for store data.

setClassLoader

public static void setClassLoader(java.lang.ClassLoader cl)

Sets class loader to use for loading stored classes.

Parameters:

cl - class loader to use, or null to use default

getInstance

public static Store getInstance(Agent agent)

Gets a store instance for an agent.

getId

protected java.lang.String getId(java.io.Serializable obj)

Gets the ID for an object. If a getter "getId()" exists, it is used to get the ID of the object. Otherwise a SHA-256 hash of the serialized object content is used as an ID.

put

public void put(java.io.Serializable obj)

Stores an object.

load

protected <T> T load(java.lang.Class<T> type,
                     java.io.File f)

Loads a stored object from a file.

getById

public <T> T getById(java.lang.Class<T> type,
                     java.lang.String id)

Gets an object in the store.

Parameters:

type - object class

id - object ID

Returns:

object with given ID, or null if not found

getByType

public <T> java.util.List<T> getByType(java.lang.Class<T> type)

Gets all objects of a given class in the store.

Parameters:

type - object class

Returns:

list of objects with specified class

remove

public boolean remove(java.io.Serializable obj)

Removes an object from the store.

Parameters:

obj - object to remove

Returns:

true if removed, false otherwise

removeById

public <T> boolean removeById(java.lang.Class<T> type,
                              java.lang.String id)

Removes an object from the store.

Parameters:

type - object class

id - object ID to remove

Returns:

true if removed, false otherwise

removeByType

public <T> boolean removeByType(java.lang.Class<T> type)

Removes all objects of a given type from the store.

Parameters:

type - objet class

Returns:

true if removed, false otherwise

delete

public boolean delete()

Deletes the data store. All objects stored are removed. Once this method is called, the store is deleted and closed. The instance of the store should no longer be used.

size

public long size()

Gets the size of the data store (in bytes).

close

public void close()

Closes the store. The instance of the store should no longer be used.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

closeQuietly

protected static void closeQuietly(java.io.InputStream is)

Closes input stream quietly.

closeQuietly

protected static void closeQuietly(java.io.OutputStream os)

Closes output stream quietly.