Thu, 11 Oct 2012 12:25:42 -0400
7200776: Implement default methods in interfaces
Summary: Add generic type analysis and default method selection algorithms
Reviewed-by: coleenp, acorn
1 /*
2 * Copyright (c) 1997, 2012, 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
21 * questions.
22 *
23 */
26 #include "precompiled.hpp"
27 #include "classfile/altHashing.hpp"
28 #include "classfile/classLoaderData.hpp"
29 #include "oops/symbol.hpp"
30 #include "runtime/os.hpp"
31 #include "memory/allocation.inline.hpp"
32 #include "memory/resourceArea.hpp"
34 Symbol::Symbol(const u1* name, int length, int refcount) : _refcount(refcount), _length(length) {
35 _identity_hash = os::random();
36 for (int i = 0; i < _length; i++) {
37 byte_at_put(i, name[i]);
38 }
39 }
41 void* Symbol::operator new(size_t sz, int len, TRAPS) {
42 int alloc_size = size(len)*HeapWordSize;
43 address res = (address) AllocateHeap(alloc_size, mtSymbol);
44 return res;
45 }
47 void* Symbol::operator new(size_t sz, int len, Arena* arena, TRAPS) {
48 int alloc_size = size(len)*HeapWordSize;
49 address res = (address)arena->Amalloc(alloc_size);
50 return res;
51 }
53 void* Symbol::operator new(size_t sz, int len, ClassLoaderData* loader_data, TRAPS) {
54 address res;
55 int alloc_size = size(len)*HeapWordSize;
56 res = (address) Metaspace::allocate(loader_data, size(len), true,
57 Metaspace::NonClassType, CHECK_NULL);
58 return res;
59 }
61 void Symbol::operator delete(void *p) {
62 assert(((Symbol*)p)->refcount() == 0, "should not call this");
63 FreeHeap(p);
64 }
66 // ------------------------------------------------------------------
67 // Symbol::equals
68 //
69 // Compares the symbol with a string of the given length.
70 bool Symbol::equals(const char* str, int len) const {
71 int l = utf8_length();
72 if (l != len) return false;
73 while (l-- > 0) {
74 if (str[l] != (char) byte_at(l))
75 return false;
76 }
77 assert(l == -1, "we should be at the beginning");
78 return true;
79 }
82 // ------------------------------------------------------------------
83 // Symbol::starts_with
84 //
85 // Tests if the symbol starts with the specified prefix of the given
86 // length.
87 bool Symbol::starts_with(const char* prefix, int len) const {
88 if (len > utf8_length()) return false;
89 while (len-- > 0) {
90 if (prefix[len] != (char) byte_at(len))
91 return false;
92 }
93 assert(len == -1, "we should be at the beginning");
94 return true;
95 }
98 // ------------------------------------------------------------------
99 // Symbol::index_of
100 //
101 // Finds if the given string is a substring of this symbol's utf8 bytes.
102 // Return -1 on failure. Otherwise return the first index where str occurs.
103 int Symbol::index_of_at(int i, const char* str, int len) const {
104 assert(i >= 0 && i <= utf8_length(), "oob");
105 if (len <= 0) return 0;
106 char first_char = str[0];
107 address bytes = (address) ((Symbol*)this)->base();
108 address limit = bytes + utf8_length() - len; // inclusive limit
109 address scan = bytes + i;
110 if (scan > limit)
111 return -1;
112 for (; scan <= limit; scan++) {
113 scan = (address) memchr(scan, first_char, (limit + 1 - scan));
114 if (scan == NULL)
115 return -1; // not found
116 assert(scan >= bytes+i && scan <= limit, "scan oob");
117 if (memcmp(scan, str, len) == 0)
118 return (int)(scan - bytes);
119 }
120 return -1;
121 }
124 char* Symbol::as_C_string(char* buf, int size) const {
125 if (size > 0) {
126 int len = MIN2(size - 1, utf8_length());
127 for (int i = 0; i < len; i++) {
128 buf[i] = byte_at(i);
129 }
130 buf[len] = '\0';
131 }
132 return buf;
133 }
135 char* Symbol::as_C_string() const {
136 int len = utf8_length();
137 char* str = NEW_RESOURCE_ARRAY(char, len + 1);
138 return as_C_string(str, len + 1);
139 }
141 char* Symbol::as_C_string_flexible_buffer(Thread* t,
142 char* buf, int size) const {
143 char* str;
144 int len = utf8_length();
145 int buf_len = len + 1;
146 if (size < buf_len) {
147 str = NEW_RESOURCE_ARRAY(char, buf_len);
148 } else {
149 str = buf;
150 }
151 return as_C_string(str, buf_len);
152 }
154 void Symbol::print_symbol_on(outputStream* st) const {
155 st = st ? st : tty;
156 int length = UTF8::unicode_length((const char*)bytes(), utf8_length());
157 const char *ptr = (const char *)bytes();
158 jchar value;
159 for (int index = 0; index < length; index++) {
160 ptr = UTF8::next(ptr, &value);
161 if (value >= 32 && value < 127 || value == '\'' || value == '\\') {
162 st->put(value);
163 } else {
164 st->print("\\u%04x", value);
165 }
166 }
167 }
169 jchar* Symbol::as_unicode(int& length) const {
170 Symbol* this_ptr = (Symbol*)this;
171 length = UTF8::unicode_length((char*)this_ptr->bytes(), utf8_length());
172 jchar* result = NEW_RESOURCE_ARRAY(jchar, length);
173 if (length > 0) {
174 UTF8::convert_to_unicode((char*)this_ptr->bytes(), result, length);
175 }
176 return result;
177 }
179 const char* Symbol::as_klass_external_name(char* buf, int size) const {
180 if (size > 0) {
181 char* str = as_C_string(buf, size);
182 int length = (int)strlen(str);
183 // Turn all '/'s into '.'s (also for array klasses)
184 for (int index = 0; index < length; index++) {
185 if (str[index] == '/') {
186 str[index] = '.';
187 }
188 }
189 return str;
190 } else {
191 return buf;
192 }
193 }
195 const char* Symbol::as_klass_external_name() const {
196 char* str = as_C_string();
197 int length = (int)strlen(str);
198 // Turn all '/'s into '.'s (also for array klasses)
199 for (int index = 0; index < length; index++) {
200 if (str[index] == '/') {
201 str[index] = '.';
202 }
203 }
204 return str;
205 }
207 // Alternate hashing for unbalanced symbol tables.
208 unsigned int Symbol::new_hash(jint seed) {
209 ResourceMark rm;
210 // Use alternate hashing algorithm on this symbol.
211 return AltHashing::murmur3_32(seed, (const jbyte*)as_C_string(), utf8_length());
212 }
214 void Symbol::print_on(outputStream* st) const {
215 if (this == NULL) {
216 st->print_cr("NULL");
217 } else {
218 st->print("Symbol: '");
219 print_symbol_on(st);
220 st->print("'");
221 st->print(" count %d", refcount());
222 }
223 }
225 // The print_value functions are present in all builds, to support the
226 // disassembler and error reporting.
227 void Symbol::print_value_on(outputStream* st) const {
228 if (this == NULL) {
229 st->print("NULL");
230 } else {
231 st->print("'");
232 for (int i = 0; i < utf8_length(); i++) {
233 st->print("%c", byte_at(i));
234 }
235 st->print("'");
236 }
237 }
239 // SymbolTable prints this in its statistics
240 NOT_PRODUCT(int Symbol::_total_count = 0;)