Mon, 11 Apr 2011 16:31:22 -0700
Merge
jjg@113 | 1 | /* |
ohair@554 | 2 | * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved. |
jjg@113 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
jjg@113 | 4 | * |
jjg@113 | 5 | * This code is free software; you can redistribute it and/or modify it |
jjg@113 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ohair@554 | 7 | * published by the Free Software Foundation. Oracle designates this |
jjg@113 | 8 | * particular file as subject to the "Classpath" exception as provided |
ohair@554 | 9 | * by Oracle in the LICENSE file that accompanied this code. |
jjg@113 | 10 | * |
jjg@113 | 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
jjg@113 | 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
jjg@113 | 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
jjg@113 | 14 | * version 2 for more details (a copy is included in the LICENSE file that |
jjg@113 | 15 | * accompanied this code). |
jjg@113 | 16 | * |
jjg@113 | 17 | * You should have received a copy of the GNU General Public License version |
jjg@113 | 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
jjg@113 | 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
jjg@113 | 20 | * |
ohair@554 | 21 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
ohair@554 | 22 | * or visit www.oracle.com if you need additional information or have any |
ohair@554 | 23 | * questions. |
jjg@113 | 24 | */ |
jjg@113 | 25 | |
jjg@113 | 26 | package com.sun.tools.javac.util; |
jjg@113 | 27 | |
jjg@113 | 28 | import java.lang.ref.SoftReference; |
jjg@113 | 29 | |
jjg@113 | 30 | /** |
jjg@113 | 31 | * Implementation of Name.Table that stores all names in a single shared |
jjg@113 | 32 | * byte array, expanding it as needed. This avoids the overhead incurred |
jjg@113 | 33 | * by using an array of bytes for each name. |
jjg@113 | 34 | * |
jjg@581 | 35 | * <p><b>This is NOT part of any supported API. |
jjg@581 | 36 | * If you write code that depends on this, you do so at your own risk. |
jjg@113 | 37 | * This code and its internal interfaces are subject to change or |
jjg@113 | 38 | * deletion without notice.</b> |
jjg@113 | 39 | */ |
jjg@113 | 40 | public class SharedNameTable extends Name.Table { |
jjg@113 | 41 | // maintain a freelist of recently used name tables for reuse. |
jjg@113 | 42 | private static List<SoftReference<SharedNameTable>> freelist = List.nil(); |
jjg@113 | 43 | |
jjg@113 | 44 | static public synchronized SharedNameTable create(Names names) { |
jjg@113 | 45 | while (freelist.nonEmpty()) { |
jjg@113 | 46 | SharedNameTable t = freelist.head.get(); |
jjg@113 | 47 | freelist = freelist.tail; |
jjg@113 | 48 | if (t != null) { |
jjg@113 | 49 | return t; |
jjg@113 | 50 | } |
jjg@113 | 51 | } |
jjg@113 | 52 | return new SharedNameTable(names); |
jjg@113 | 53 | } |
jjg@113 | 54 | |
jjg@113 | 55 | static private synchronized void dispose(SharedNameTable t) { |
jjg@113 | 56 | freelist = freelist.prepend(new SoftReference<SharedNameTable>(t)); |
jjg@113 | 57 | } |
jjg@113 | 58 | |
jjg@113 | 59 | /** The hash table for names. |
jjg@113 | 60 | */ |
jjg@113 | 61 | private NameImpl[] hashes; |
jjg@113 | 62 | |
jjg@113 | 63 | /** The shared byte array holding all encountered names. |
jjg@113 | 64 | */ |
jjg@113 | 65 | public byte[] bytes; |
jjg@113 | 66 | |
jjg@113 | 67 | /** The mask to be used for hashing |
jjg@113 | 68 | */ |
jjg@113 | 69 | private int hashMask; |
jjg@113 | 70 | |
jjg@113 | 71 | /** The number of filled bytes in `names'. |
jjg@113 | 72 | */ |
jjg@113 | 73 | private int nc = 0; |
jjg@113 | 74 | |
jjg@113 | 75 | /** Allocator |
jjg@113 | 76 | * @param names The main name table |
jjg@113 | 77 | * @param hashSize the (constant) size to be used for the hash table |
jjg@113 | 78 | * needs to be a power of two. |
jjg@113 | 79 | * @param nameSize the initial size of the name table. |
jjg@113 | 80 | */ |
jjg@113 | 81 | public SharedNameTable(Names names, int hashSize, int nameSize) { |
jjg@113 | 82 | super(names); |
jjg@113 | 83 | hashMask = hashSize - 1; |
jjg@113 | 84 | hashes = new NameImpl[hashSize]; |
jjg@113 | 85 | bytes = new byte[nameSize]; |
jjg@113 | 86 | |
jjg@113 | 87 | } |
jjg@113 | 88 | |
jjg@113 | 89 | public SharedNameTable(Names names) { |
jjg@113 | 90 | this(names, 0x8000, 0x20000); |
jjg@113 | 91 | } |
jjg@113 | 92 | |
jjg@113 | 93 | @Override |
jjg@113 | 94 | public Name fromChars(char[] cs, int start, int len) { |
jjg@113 | 95 | int nc = this.nc; |
jjg@113 | 96 | byte[] bytes = this.bytes; |
jjg@113 | 97 | while (nc + len * 3 >= bytes.length) { |
jjg@113 | 98 | // System.err.println("doubling name buffer of length " + names.length + " to fit " + len + " chars");//DEBUG |
jjg@113 | 99 | byte[] newnames = new byte[bytes.length * 2]; |
jjg@113 | 100 | System.arraycopy(bytes, 0, newnames, 0, bytes.length); |
jjg@113 | 101 | bytes = this.bytes = newnames; |
jjg@113 | 102 | } |
jjg@113 | 103 | int nbytes = Convert.chars2utf(cs, start, bytes, nc, len) - nc; |
jjg@113 | 104 | int h = hashValue(bytes, nc, nbytes) & hashMask; |
jjg@113 | 105 | NameImpl n = hashes[h]; |
jjg@113 | 106 | while (n != null && |
jjg@113 | 107 | (n.getByteLength() != nbytes || |
jjg@113 | 108 | !equals(bytes, n.index, bytes, nc, nbytes))) { |
jjg@113 | 109 | n = n.next; |
jjg@113 | 110 | } |
jjg@113 | 111 | if (n == null) { |
jjg@113 | 112 | n = new NameImpl(this); |
jjg@113 | 113 | n.index = nc; |
jjg@113 | 114 | n.length = nbytes; |
jjg@113 | 115 | n.next = hashes[h]; |
jjg@113 | 116 | hashes[h] = n; |
jjg@113 | 117 | this.nc = nc + nbytes; |
jjg@113 | 118 | if (nbytes == 0) { |
jjg@113 | 119 | this.nc++; |
jjg@113 | 120 | } |
jjg@113 | 121 | } |
jjg@113 | 122 | return n; |
jjg@113 | 123 | } |
jjg@113 | 124 | |
jjg@113 | 125 | @Override |
jjg@113 | 126 | public Name fromUtf(byte[] cs, int start, int len) { |
jjg@113 | 127 | int h = hashValue(cs, start, len) & hashMask; |
jjg@113 | 128 | NameImpl n = hashes[h]; |
jjg@113 | 129 | byte[] names = this.bytes; |
jjg@113 | 130 | while (n != null && |
jjg@113 | 131 | (n.getByteLength() != len || !equals(names, n.index, cs, start, len))) { |
jjg@113 | 132 | n = n.next; |
jjg@113 | 133 | } |
jjg@113 | 134 | if (n == null) { |
jjg@113 | 135 | int nc = this.nc; |
jjg@113 | 136 | while (nc + len > names.length) { |
jjg@113 | 137 | // System.err.println("doubling name buffer of length + " + names.length + " to fit " + len + " bytes");//DEBUG |
jjg@113 | 138 | byte[] newnames = new byte[names.length * 2]; |
jjg@113 | 139 | System.arraycopy(names, 0, newnames, 0, names.length); |
jjg@113 | 140 | names = this.bytes = newnames; |
jjg@113 | 141 | } |
jjg@113 | 142 | System.arraycopy(cs, start, names, nc, len); |
jjg@113 | 143 | n = new NameImpl(this); |
jjg@113 | 144 | n.index = nc; |
jjg@113 | 145 | n.length = len; |
jjg@113 | 146 | n.next = hashes[h]; |
jjg@113 | 147 | hashes[h] = n; |
jjg@113 | 148 | this.nc = nc + len; |
jjg@113 | 149 | if (len == 0) { |
jjg@113 | 150 | this.nc++; |
jjg@113 | 151 | } |
jjg@113 | 152 | } |
jjg@113 | 153 | return n; |
jjg@113 | 154 | } |
jjg@113 | 155 | |
jjg@113 | 156 | @Override |
jjg@113 | 157 | public void dispose() { |
jjg@113 | 158 | dispose(this); |
jjg@113 | 159 | } |
jjg@113 | 160 | |
jjg@113 | 161 | static class NameImpl extends Name { |
jjg@113 | 162 | /** The next name occupying the same hash bucket. |
jjg@113 | 163 | */ |
jjg@113 | 164 | NameImpl next; |
jjg@113 | 165 | |
jjg@113 | 166 | /** The index where the bytes of this name are stored in the global name |
jjg@113 | 167 | * buffer `byte'. |
jjg@113 | 168 | */ |
jjg@113 | 169 | int index; |
jjg@113 | 170 | |
jjg@113 | 171 | /** The number of bytes in this name. |
jjg@113 | 172 | */ |
jjg@113 | 173 | int length; |
jjg@113 | 174 | |
jjg@113 | 175 | NameImpl(SharedNameTable table) { |
jjg@113 | 176 | super(table); |
jjg@113 | 177 | } |
jjg@113 | 178 | |
jjg@113 | 179 | @Override |
jjg@113 | 180 | public int getIndex() { |
jjg@113 | 181 | return index; |
jjg@113 | 182 | } |
jjg@113 | 183 | |
jjg@113 | 184 | @Override |
jjg@113 | 185 | public int getByteLength() { |
jjg@113 | 186 | return length; |
jjg@113 | 187 | } |
jjg@113 | 188 | |
jjg@113 | 189 | @Override |
jjg@113 | 190 | public byte getByteAt(int i) { |
jjg@113 | 191 | return getByteArray()[index + i]; |
jjg@113 | 192 | } |
jjg@113 | 193 | |
jjg@113 | 194 | @Override |
jjg@113 | 195 | public byte[] getByteArray() { |
jjg@113 | 196 | return ((SharedNameTable) table).bytes; |
jjg@113 | 197 | } |
jjg@113 | 198 | |
jjg@113 | 199 | @Override |
jjg@113 | 200 | public int getByteOffset() { |
jjg@113 | 201 | return index; |
jjg@113 | 202 | } |
jjg@113 | 203 | |
jjg@113 | 204 | /** Return the hash value of this name. |
jjg@113 | 205 | */ |
jjg@113 | 206 | public int hashCode() { |
jjg@113 | 207 | return index; |
jjg@113 | 208 | } |
jjg@113 | 209 | |
jjg@113 | 210 | /** Is this name equal to other? |
jjg@113 | 211 | */ |
jjg@113 | 212 | public boolean equals(Object other) { |
jjg@113 | 213 | if (other instanceof Name) |
jjg@113 | 214 | return |
jjg@113 | 215 | table == ((Name)other).table && index == ((Name) other).getIndex(); |
jjg@113 | 216 | else return false; |
jjg@113 | 217 | } |
jjg@113 | 218 | |
jjg@113 | 219 | } |
jjg@113 | 220 | |
jjg@113 | 221 | } |