jjg@113: /* xdono@117: * Copyright 1999-2008 Sun Microsystems, Inc. All Rights Reserved. jjg@113: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. jjg@113: * jjg@113: * This code is free software; you can redistribute it and/or modify it jjg@113: * under the terms of the GNU General Public License version 2 only, as jjg@113: * published by the Free Software Foundation. Sun designates this jjg@113: * particular file as subject to the "Classpath" exception as provided jjg@113: * by Sun in the LICENSE file that accompanied this code. jjg@113: * jjg@113: * This code is distributed in the hope that it will be useful, but WITHOUT jjg@113: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or jjg@113: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License jjg@113: * version 2 for more details (a copy is included in the LICENSE file that jjg@113: * accompanied this code). jjg@113: * jjg@113: * You should have received a copy of the GNU General Public License version jjg@113: * 2 along with this work; if not, write to the Free Software Foundation, jjg@113: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. jjg@113: * jjg@113: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, jjg@113: * CA 95054 USA or visit www.sun.com if you need additional information or jjg@113: * have any questions. jjg@113: */ jjg@113: jjg@113: package com.sun.tools.javac.util; jjg@113: jjg@113: import java.lang.ref.WeakReference; jjg@113: jjg@113: /** jjg@113: * Implementation of Name.Table that stores names in individual arrays jjg@113: * using weak references. It is recommended for use when a single shared jjg@113: * byte array is unsuitable. jjg@113: * jjg@113: *

This is NOT part of any API supported by Sun Microsystems. If jjg@113: * you write code that depends on this, you do so at your own risk. jjg@113: * This code and its internal interfaces are subject to change or jjg@113: * deletion without notice. jjg@113: */ jjg@113: public class UnsharedNameTable extends Name.Table { jjg@113: static public Name.Table create(Names names) { jjg@113: return new UnsharedNameTable(names); jjg@113: } jjg@113: jjg@113: static class HashEntry extends WeakReference { jjg@113: HashEntry next; jjg@113: HashEntry(NameImpl referent) { jjg@113: super(referent); jjg@113: } jjg@113: } jjg@113: jjg@113: /** The hash table for names. jjg@113: */ jjg@113: private HashEntry[] hashes = null; jjg@113: jjg@113: /** The mask to be used for hashing jjg@113: */ jjg@113: private int hashMask; jjg@113: jjg@113: /** Index counter for names in this table. jjg@113: */ jjg@113: public int index; jjg@113: jjg@113: /** Allocator jjg@113: * @param names The main name table jjg@113: * @param hashSize the (constant) size to be used for the hash table jjg@113: * needs to be a power of two. jjg@113: */ jjg@113: public UnsharedNameTable(Names names, int hashSize) { jjg@113: super(names); jjg@113: hashMask = hashSize - 1; jjg@113: hashes = new HashEntry[hashSize]; jjg@113: } jjg@113: jjg@113: public UnsharedNameTable(Names names) { jjg@113: this(names, 0x8000); jjg@113: } jjg@113: jjg@113: jjg@113: @Override jjg@113: public Name fromChars(char[] cs, int start, int len) { jjg@113: byte[] name = new byte[len * 3]; jjg@113: int nbytes = Convert.chars2utf(cs, start, name, 0, len); jjg@113: return fromUtf(name, 0, nbytes); jjg@113: } jjg@113: jjg@113: @Override jjg@113: public Name fromUtf(byte[] cs, int start, int len) { jjg@113: int h = hashValue(cs, start, len) & hashMask; jjg@113: jjg@113: HashEntry element = hashes[h]; jjg@113: jjg@113: NameImpl n = null; jjg@113: jjg@113: HashEntry previousNonNullTableEntry = null; jjg@113: HashEntry firstTableEntry = element; jjg@113: jjg@113: while (element != null) { jjg@113: if (element == null) { jjg@113: break; jjg@113: } jjg@113: jjg@113: n = element.get(); jjg@113: jjg@113: if (n == null) { jjg@113: if (firstTableEntry == element) { jjg@113: hashes[h] = firstTableEntry = element.next; jjg@113: } jjg@113: else { jjg@113: assert previousNonNullTableEntry != null : "previousNonNullTableEntry cannot be null here."; jjg@113: previousNonNullTableEntry.next = element.next; jjg@113: } jjg@113: } jjg@113: else { jjg@113: if (n.getByteLength() == len && equals(n.bytes, 0, cs, start, len)) { jjg@113: return n; jjg@113: } jjg@113: previousNonNullTableEntry = element; jjg@113: } jjg@113: jjg@113: element = element.next; jjg@113: } jjg@113: jjg@113: byte[] bytes = new byte[len]; jjg@113: System.arraycopy(cs, start, bytes, 0, len); jjg@113: n = new NameImpl(this, bytes, index++); jjg@113: jjg@113: System.arraycopy(cs, start, n.bytes, 0, len); jjg@113: jjg@113: HashEntry newEntry = new HashEntry(n); jjg@113: jjg@113: if (previousNonNullTableEntry == null) { // We are not the first name with that hashCode. jjg@113: hashes[h] = newEntry; jjg@113: } jjg@113: else { jjg@113: assert previousNonNullTableEntry.next == null : "previousNonNullTableEntry.next must be null."; jjg@113: previousNonNullTableEntry.next = newEntry; jjg@113: } jjg@113: jjg@113: return n; jjg@113: } jjg@113: jjg@113: @Override jjg@113: public void dispose() { jjg@113: hashes = null; jjg@113: } jjg@113: jjg@113: static class NameImpl extends Name { jjg@113: NameImpl(UnsharedNameTable table, byte[] bytes, int index) { jjg@113: super(table); jjg@113: this.bytes = bytes; jjg@113: this.index = index; jjg@113: } jjg@113: jjg@113: final byte[] bytes; jjg@113: final int index; jjg@113: jjg@113: @Override jjg@113: public int getIndex() { jjg@113: return index; jjg@113: } jjg@113: jjg@113: @Override jjg@113: public int getByteLength() { jjg@113: return bytes.length; jjg@113: } jjg@113: jjg@113: @Override jjg@113: public byte getByteAt(int i) { jjg@113: return bytes[i]; jjg@113: } jjg@113: jjg@113: @Override jjg@113: public byte[] getByteArray() { jjg@113: return bytes; jjg@113: } jjg@113: jjg@113: @Override jjg@113: public int getByteOffset() { jjg@113: return 0; jjg@113: } jjg@113: jjg@113: } jjg@113: jjg@113: }