org.grouplens.lenskit.symbols

Class Symbol

java.lang.Object

org.grouplens.lenskit.symbols.Symbol

All Implemented Interfaces:

Serializable

public final class Symbol
extends Object
implements Serializable

Interface to persistent symbols.

A Symbol is an inexpensive object that behaves like a singleton -- except that you can create as many as you want. Each Symbol is created with a String, and a unique Symbol is assigned to this String. Any fetches of that String will return the same Symbol.

Symbols cannot be constructed, but must be fetched through the "of" operator.

Symbols are hashable, because they are singletons, so the default hashCode based on Object address should work.

Author:

GroupLens Research

See Also:

Serialized Form

Method Summary

Methods

Modifier and Type	Method and Description
String	getName() Get the name for a symbol.
static Symbol	of(String name) Get a unique symbol for .
String	toString()
<T> TypedSymbol<T>	withType(Class<T> type) Make a typed symbol from this symbol.

Methods inherited from class java.lang.Object

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

Method Detail

of

public static Symbol of(String name)

Get a unique symbol for .

Parameters:

name - the name for this symbol during this execution of the program

Returns:

the new symbol

getName

public String getName()

Get the name for a symbol.

Returns:

the string name that was used to create the symbol

toString

public String toString()

Overrides:

toString in class Object

withType

public <T> TypedSymbol<T> withType(Class<T> type)

Make a typed symbol from this symbol.

Type Parameters:

T - The type.

Parameters:

type - The type.

Returns:

A typed symbol with the specified type and this symbol.