-
-
Notifications
You must be signed in to change notification settings - Fork 938
Expand file tree
/
Copy pathMetaClass.java
More file actions
152 lines (127 loc) · 5.79 KB
/
MetaClass.java
File metadata and controls
152 lines (127 loc) · 5.79 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/***** BEGIN LICENSE BLOCK *****
* Version: EPL 2.0/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Eclipse Public
* License Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.eclipse.org/legal/epl-v20.html
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* Copyright (C) 2002-2004 Jan Arne Petersen <jpetersen@uni-bonn.de>
* Copyright (C) 2004-2006 Thomas E Enebo <enebo@acm.org>
* Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the EPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the EPL, the GPL or the LGPL.
***** END LICENSE BLOCK *****/
package org.jruby;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.util.cli.Options;
import org.jruby.util.log.Logger;
import org.jruby.util.log.LoggerFactory;
import static org.jruby.api.Access.classClass;
import static org.jruby.api.Error.typeError;
public final class MetaClass extends RubyClass {
/**
* rb_class_boot for meta classes ({@link #makeMetaClass(ThreadContext, RubyClass)})
*/
MetaClass(Ruby runtime, RubyClass superClass, RubyBasicObject attached) {
super(runtime, superClass, false);
metaClassInit(superClass, attached);
if (LOG_SINGLETONS || LOG_SINGLETONS_VERBOSE) {
logSingleton(runtime, superClass, attached);
}
}
/**
* This is an internal API only used by Ruby constructor before ThreadContext exists. This is for bootstrapping
* only.
* @param runtime
* @param superClass
* @param Class
* @param attached
*/
MetaClass(Ruby runtime, RubyClass superClass, RubyClass Class, RubyBasicObject attached) {
super(runtime, superClass, Class);
metaClassInit(superClass, attached);
}
private void metaClassInit(RubyClass superClass, RubyBasicObject attached) {
this.attached = attached;
// use same ClassIndex as metaclass, since we're technically still of that type
classIndex(superClass.getClassIndex());
superClass.addSubclass(this);
}
private static void logSingleton(Ruby runtime, RubyClass superClass, RubyBasicObject attached) {
if (runtime.isBooting()) return; // don't log singleton created during boot
String attachedString = attached == null ? "null object" : "object of type " + attached.getMetaClass();
LOG.info("singleton class created for type " + superClass + " attached to " + attachedString);
if (LOG_SINGLETONS_VERBOSE) {
LOG.info(new Exception("singleton creation stack trace"));
}
}
@Override
public final IRubyObject allocate(ThreadContext context) {
throw typeError(context, "can't create instance of virtual class");
}
@Override
public boolean isSingleton() {
return true;
}
/**
* rb_make_metaclass
* @param superClass
* @return singleton-class for this (singleton) class
*/
@Override
public RubyClass makeMetaClass(ThreadContext context, RubyClass superClass) {
MetaClass klass = new MetaClass(context.runtime, getSuperSingletonMetaClass(context), this);
setMetaClass(klass);
// Foo.singleton_class.singleton_class: #<Class:#<Class:Foo>>
// #<Class:#<Class:Foo>>'s singleton_class == #<Class:#<Class:Foo>>
klass.setMetaClass(klass);
return klass;
}
private RubyClass getSuperSingletonMetaClass(ThreadContext context) {
if (attached instanceof RubyClass att) {
RubyClass superClass = att.superClass();
if (superClass != null) superClass = superClass.getRealClass();
// #<Class:BasicObject>'s singleton class == Class.singleton_class
// Context should be safe here as we never make a metaclass from a metaclass before first TC is made.
return superClass == null ?
classClass(context).singletonClass(context) :
superClass.getMetaClass().singletonClass(context);
}
return getSuperClass().getRealClass().getMetaClass(); // NOTE: is this correct?
}
@Override
RubyClass toSingletonClass(ThreadContext context, RubyBasicObject target) {
return attached == target ? this : super.toSingletonClass(context, target);
}
@Override
public IRubyObject attached_object(ThreadContext context) {
return attached;
}
public RubyBasicObject getAttached() {
return attached;
}
public void setAttached(RubyBasicObject attached) {
this.attached = attached;
}
private RubyBasicObject attached;
private static final Logger LOG = LoggerFactory.getLogger(MetaClass.class);
private static final boolean LOG_SINGLETONS = Options.LOG_SINGLETONS.load();
private static final boolean LOG_SINGLETONS_VERBOSE = Options.LOG_SINGLETONS_VERBOSE.load();
}