Package com.oracle.truffle.api.staticobject

Class StaticShape<T>

java.lang.Object

com.oracle.truffle.api.staticobject.StaticShape<T>

Type Parameters:

T - the default or the user-defined factory interface to allocate static objects

public abstract class StaticShape<T>
extends Object

A StaticShape is an immutable descriptor of the layout of a static object and is a good entry point to learn about the Static Object Model. Here is an overview:

• newBuilder(TruffleLanguage) returns a StaticShape.Builder object that can be used to register static properties and to generate a new static shape by calling one of its build methods.
• getFactory() returns an implementation of the default or the user-defined factory interface that must be used to allocate static objects with the current shape.
• Property values stored in a static object of a given shape can be accessed by the StaticProperty instances registered to the builder that generated that shape or one of its parent shapes. Note that static shapes do not store the list of static properties associated to them. It is up to the user to store this information when required, for example in a class that contains references to the static shape and the list of static properties.

StaticShape cannot be subclassed by custom implementations and, when required, it allows static properties to check that the receiver object matches the expected shape.

Since:

21.3.0

See Also:

• newBuilder(TruffleLanguage)
• StaticShape.Builder
• StaticProperty
• DefaultStaticProperty
• DefaultStaticObjectFactory

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	StaticShape.Builder	Builder class to construct StaticShape instances.

Method Summary

Modifier and Type	Method	Description
final T	getFactory()	Returns an instance of the default or the user-defined factory interface that must be used to allocate static objects with the current shape.
static StaticShape.Builder	newBuilder(TruffleLanguage<?> language)	Creates a new static shape builder.

Methods inherited from class java.lang.Object

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

Method Details

newBuilder

public static StaticShape.Builder newBuilder(TruffleLanguage<?> language)

Creates a new static shape builder. The builder instance is not thread-safe and must not be used from multiple threads at the same time. Users of the Static Object Model are expected to define custom subtypes of StaticProperty or use DefaultStaticProperty, a trivial default implementation. In both cases, static properties must be registered to a static shape builder using StaticShape.Builder.property(StaticProperty, Class, boolean). Then, after allocating a StaticShape instance with one of the StaticShape.Builder.build() methods and allocating a static object using the factory class provided by getFactory(), users can call the accessor methods defined in StaticProperty to get and set property values stored in a static object instance.

Parameters:

language - an instance of the TruffleLanguage that uses the Static Object Model

Returns:

a new static shape builder

Throws:

NullPointerException - if language is null

Since:

21.3.0

See Also:

• StaticShape
• StaticProperty
• DefaultStaticProperty
• DefaultStaticObjectFactory

getFactory

public final T getFactory()

Returns an instance of the default or the user-defined factory interface that must be used to allocate static objects with the current shape.

Since:

21.3.0

See Also:

• StaticShape.Builder.build()
• StaticShape.Builder.build(StaticShape)
• StaticShape.Builder.build(Class, Class)