1 /*
 2  * Copyright (c) 2020, 2024, 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.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
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23  */
24 
25 #ifndef SHARE_CDS_CLASSLISTWRITER_HPP
26 #define SHARE_CDS_CLASSLISTWRITER_HPP
27 
28 #include "runtime/javaThread.hpp"
29 #include "runtime/mutexLocker.hpp"
30 #include "utilities/ostream.hpp"
31 
32 class ClassFileStream;
33 
34 class ClassListWriter {
35 #if INCLUDE_CDS
36   class IDTable;
37   class WriteResolveConstantsCLDClosure;
38 
39   static fileStream* _classlist_file;
40   static IDTable* _id_table;
41   static int _total_ids;
42   MutexLocker _locker;
43 
44   static int get_id(const InstanceKlass* k);
45   static bool has_id(const InstanceKlass* k);
46   static void assert_locked() { assert_lock_strong(ClassListFile_lock); }
47   static void write_resolved_constants_for(InstanceKlass* klass);
48 public:
49   ClassListWriter() : _locker(Thread::current(), ClassListFile_lock, Mutex::_no_safepoint_check_flag) {}
50 
51   outputStream* stream() {
52     return _classlist_file;
53   }
54 
55   void handle_class_unloading(const InstanceKlass* klass);
56 
57   static bool is_enabled() {
58     return _classlist_file != nullptr && _classlist_file->is_open();
59   }
60 
61 #else
62 public:
63   static bool is_enabled() {
64     return false;
65   }
66 #endif // INCLUDE_CDS
67 
68 
69   static void init() NOT_CDS_RETURN;
70   static void write(const InstanceKlass* k, const ClassFileStream* cfs) NOT_CDS_RETURN;
71   static void write_to_stream(const InstanceKlass* k, outputStream* stream, const ClassFileStream* cfs = nullptr) NOT_CDS_RETURN;
72   static void write_resolved_constants() NOT_CDS_RETURN;
73   static void delete_classlist() NOT_CDS_RETURN;
74 };
75 
76 #endif // SHARE_CDS_CLASSLISTWRITER_HPP