Mercurial > hg > graal-compiler

comparison graal/com.oracle.truffle.api/src/com/oracle/truffle/api/TruffleLanguage.java @ 21522:28cbfacd0518

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Merge
author Gilles Duboscq <gilles.m.duboscq@oracle.com>
date Thu, 28 May 2015 17:44:05 +0200
parents 3286fb5fea4a
children 31fc2fce38f3
comparison
equal deleted inserted replaced
21521:107300758a4e 21522:28cbfacd0518
1 /*
2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package com.oracle.truffle.api;
26
27 import com.oracle.truffle.api.impl.Accessor;
28 import com.oracle.truffle.api.source.Source;
29 import com.oracle.truffle.api.vm.TruffleVM;
30 import com.oracle.truffle.api.vm.TruffleVM.Language;
31 import java.io.IOException;
32 import java.io.Reader;
33 import java.io.Writer;
34 import java.lang.annotation.ElementType;
35 import java.lang.annotation.Retention;
36 import java.lang.annotation.RetentionPolicy;
37 import java.lang.annotation.Target;
38 import java.lang.reflect.Constructor;
39
40 /**
41 * An entry point for everyone who wants to implement a Truffle based language. By providing
42 * implementation of this type and registering it using {@link Registration} annotation, your
43 * language becomes accessible to users of the {@link TruffleVM Truffle virtual machine} - all they
44 * will need to do is to include your JAR into their application and all the Truffle goodies (multi
45 * language support, multi tennat hosting, debugging, etc.) will be made available to them.
46 */
47 public abstract class TruffleLanguage {
48 private final Env env;
49
50 /**
51 * Constructor to be called by subclasses.
52 *
53 * @param env language environment that will be available via {@link #env()} method to
54 * subclasses.
55 */
56 protected TruffleLanguage(Env env) {
57 this.env = env;
58 }
59
60 /**
61 * The annotation to use to register your language to the {@link TruffleVM Truffle} system. By
62 * annotating your implementation of {@link TruffleLanguage} by this annotation you are just a
63 * <em>one JAR drop to the classpath</em> away from your users. Once they include your JAR in
64 * their application, your language will be available to the {@link TruffleVM Truffle virtual
65 * machine}.
66 */
67 @Retention(RetentionPolicy.SOURCE)
68 @Target(ElementType.TYPE)
69 public @interface Registration {
70 /**
71 * Unique name of your language. This name will be exposed to users via the
72 * {@link Language#getName()} getter.
73 *
74 * @return identifier of your language
75 */
76 String name();
77
78 /**
79 * List of mimetypes associated with your language. Users will use them (directly or
80 * inderectly) when {@link TruffleVM#eval(java.lang.String, java.lang.String) executing}
81 * their code snippets or their {@link TruffleVM#eval(java.net.URI) files}.
82 *
83 * @return array of mime types assigned to your language files
84 */
85 String[] mimeType();
86 }
87
88 protected final Env env() {
89 if (this.env == null) {
90 throw new NullPointerException("Accessing env before initialization is finished");
91 }
92 return this.env;
93 }
94
95 protected abstract Object eval(Source code) throws IOException;
96
97 /**
98 * Called when some other language is seeking for a global symbol. This method is supposed to do
99 * lazy binding, e.g. there is no need to export symbols in advance, it is fine to wait until
100 * somebody asks for it (by calling this method).
101 * <p>
102 * The exported object can either be <code>TruffleObject</code> (e.g. a native object from the
103 * other language) to support interoperability between languages or one of Java primitive
104 * wrappers ( {@link Integer}, {@link Double}, {@link Short}, etc.).
105 *
106 * @param globalName the name of the global symbol to find
107 * @return an exported object or <code>null</code>, if the symbol does not represent anything
108 * meaningful in this language
109 */
110 protected abstract Object findExportedSymbol(String globalName);
111
112 /**
113 * Returns global object for the language.
114 * <p>
115 * The object is expected to be <code>TruffleObject</code> (e.g. a native object from the other
116 * language) but technically it can be one of Java primitive wrappers ({@link Integer},
117 * {@link Double}, {@link Short}, etc.).
118 *
119 * @return the global object or <code>null</code> if the language does not support such concept
120 */
121 protected abstract Object getLanguageGlobal();
122
123 /**
124 * Checks whether the object is provided by this language.
125 *
126 * @param object the object to check
127 * @return <code>true</code> if this language can deal with such object in native way
128 */
129 protected abstract boolean isObjectOfLanguage(Object object);
130
131 /**
132 * Represents execution environment of the {@link TruffleLanguage}. Each active
133 * {@link TruffleLanguage} receives instance of the environment before any code is executed upon
134 * it. The environment has knowledge of all active languages and can exchange symbols between
135 * them.
136 */
137 public static final class Env {
138 private final TruffleVM vm;
139 private final TruffleLanguage lang;
140 private final Reader in;
141 private final Writer err;
142 private final Writer out;
143
144 Env(TruffleVM vm, Constructor<?> langConstructor, Writer out, Writer err, Reader in) {
145 this.vm = vm;
146 this.in = in;
147 this.err = err;
148 this.out = out;
149 try {
150 this.lang = (TruffleLanguage) langConstructor.newInstance(this);
151 } catch (Exception ex) {
152 throw new IllegalStateException("Cannot construct language " + langConstructor.getDeclaringClass().getName(), ex);
153 }
154 }
155
156 /**
157 * Asks the environment to go through other registered languages and find whether they
158 * export global symbol of specified name. The expected return type is either
159 * <code>TruffleObject</code>, or one of wrappers of Java primitive types ({@link Integer},
160 * {@link Double}).
161 *
162 * @param globalName the name of the symbol to search for
163 * @return object representing the symbol or <code>null</code>
164 */
165 public Object importSymbol(String globalName) {
166 return API.importSymbol(vm, lang, globalName);
167 }
168
169 /**
170 * Input associated with this {@link TruffleVM}.
171 *
172 * @return reader, never <code>null</code>
173 */
174 public Reader stdIn() {
175 return in;
176 }
177
178 /**
179 * Standard output writer for this {@link TruffleVM}.
180 *
181 * @return writer, never <code>null</code>
182 */
183 public Writer stdOut() {
184 return out;
185 }
186
187 /**
188 * Standard error writer for this {@link TruffleVM}.
189 *
190 * @return writer, never <code>null</code>
191 */
192 public Writer stdErr() {
193 return err;
194 }
195 }
196
197 private static final AccessAPI API = new AccessAPI();
198
199 private static final class AccessAPI extends Accessor {
200 @Override
201 protected TruffleLanguage attachEnv(TruffleVM vm, Constructor<?> langClazz, Writer stdOut, Writer stdErr, Reader stdIn) {
202 Env env = new Env(vm, langClazz, stdOut, stdErr, stdIn);
203 return env.lang;
204 }
205
206 @Override
207 public Object importSymbol(TruffleVM vm, TruffleLanguage queryingLang, String globalName) {
208 return super.importSymbol(vm, queryingLang, globalName);
209 }
210
211 @Override
212 protected Object eval(TruffleLanguage l, Source s) throws IOException {
213 return l.eval(s);
214 }
215
216 @Override
217 protected Object findExportedSymbol(TruffleLanguage l, String globalName) {
218 return l.findExportedSymbol(globalName);
219 }
220
221 @Override
222 protected Object languageGlobal(TruffleLanguage l) {
223 return l.getLanguageGlobal();
224 }
225 }
226 }