Mercurial > hg > truffle
view truffle/com.oracle.truffle.api.object/src/com/oracle/truffle/api/object/Layout.java @ 22325:414e82b9fc35
Release 0.9 is out, let's remove deprecated elements from the API
author | Jaroslav Tulach <jaroslav.tulach@oracle.com> |
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date | Fri, 23 Oct 2015 20:23:00 +0200 |
parents | 8bc57c7bbf88 |
children | bb3c03f2442d |
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/* * Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.oracle.truffle.api.object; import java.util.EnumSet; import java.util.ServiceLoader; import com.oracle.truffle.api.object.Shape.Allocator; /** * Describes layout and behavior of a {@link DynamicObject} subclass and is used to create shapes. * * An object may change its shape but only to shapes of the same layout. */ public abstract class Layout { public static final String OPTION_PREFIX = "truffle.object."; private static final LayoutFactory LAYOUT_FACTORY = loadLayoutFactory(); /** * Specifies the allowed implicit casts between primitive types without losing type information. */ public enum ImplicitCast { IntToDouble, IntToLong, } /** * Creates a new {@link Builder}. */ public static Builder newLayout() { return new Builder(); } /** * Equivalent to {@code Layout.newLayout().build()}. */ public static Layout createLayout() { return newLayout().build(); } public abstract DynamicObject newInstance(Shape shape); public abstract Class<? extends DynamicObject> getType(); public abstract Shape createShape(ObjectType operations); public abstract Shape createShape(ObjectType operations, Object sharedData); public abstract Shape createShape(ObjectType operations, Object sharedData, int id); /** * Create an allocator for static property creation. Reserves all array extension slots. */ public abstract Allocator createAllocator(); protected static LayoutFactory getFactory() { return LAYOUT_FACTORY; } private static LayoutFactory loadLayoutFactory() { LayoutFactory bestLayoutFactory = null; String layoutFactoryImplClassName = System.getProperty(OPTION_PREFIX + "LayoutFactory"); if (layoutFactoryImplClassName != null) { Class<?> clazz; try { clazz = Class.forName(layoutFactoryImplClassName); } catch (ClassNotFoundException e) { throw new RuntimeException(e); } try { bestLayoutFactory = (LayoutFactory) clazz.newInstance(); } catch (InstantiationException | IllegalAccessException e) { throw new AssertionError(e); } } else { ServiceLoader<LayoutFactory> serviceLoader = ServiceLoader.load(LayoutFactory.class, Layout.class.getClassLoader()); for (LayoutFactory currentLayoutFactory : serviceLoader) { if (bestLayoutFactory == null) { bestLayoutFactory = currentLayoutFactory; } else if (currentLayoutFactory.getPriority() >= bestLayoutFactory.getPriority()) { assert currentLayoutFactory.getPriority() != bestLayoutFactory.getPriority(); bestLayoutFactory = currentLayoutFactory; } } } if (bestLayoutFactory == null) { throw new AssertionError("LayoutFactory not found"); } return bestLayoutFactory; } /** * Layout builder. * * @see Layout */ public static final class Builder { private EnumSet<ImplicitCast> allowedImplicitCasts; /** * Create a new layout builder. */ private Builder() { this.allowedImplicitCasts = EnumSet.noneOf(ImplicitCast.class); } /** * Build {@link Layout} from the configuration in this builder. */ public Layout build() { return Layout.getFactory().createLayout(this); } /** * Set the allowed implicit casts in this layout. * * @see Layout.ImplicitCast */ public Builder setAllowedImplicitCasts(EnumSet<ImplicitCast> allowedImplicitCasts) { this.allowedImplicitCasts = allowedImplicitCasts; return this; } /** * Add an allowed implicit cast in this layout. * * @see Layout.ImplicitCast */ public Builder addAllowedImplicitCast(ImplicitCast allowedImplicitCast) { this.allowedImplicitCasts.add(allowedImplicitCast); return this; } } protected static EnumSet<ImplicitCast> getAllowedImplicitCasts(Builder builder) { return builder.allowedImplicitCasts; } }