| /* |
| * The Apache Software License, Version 1.1 |
| * |
| * |
| * Copyright (c) 1999 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, |
| * if any, must include the following acknowledgment: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowledgment may appear in the software itself, |
| * if and wherever such third-party acknowledgments normally appear. |
| * |
| * 4. The names "Xerces" and "Apache Software Foundation" must |
| * not be used to endorse or promote products derived from this |
| * software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache", |
| * nor may "Apache" appear in their name, without prior written |
| * permission of the Apache Software Foundation. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation and was |
| * originally based on software copyright (c) 1999, International |
| * Business Machines, Inc., http://www.apache.org. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| |
| package org.apache.xerces.utils; |
| |
| /** |
| * |
| * @version |
| */ |
| public final class SymbolCache { |
| // |
| // Symbol Cache |
| // |
| public static final int CHAR_OFFSET = 0; |
| public static final int INDEX_OFFSET = 1; |
| public static final int NEXT_OFFSET = 2; |
| public static final int CACHE_RECORD_SIZE = 3; |
| // |
| public static final int INITIAL_CACHE_RECORD_COUNT = 4; // start with 4 entries per level |
| // |
| public char[] fSymbolChars = new char[8192]; |
| public int fSymbolCharsOffset = 0; |
| public int[][] fCacheLines = new int[8][]; |
| public int fCacheLineCount = 0; |
| // |
| // |
| // |
| public SymbolCache() { |
| fCacheLines[fCacheLineCount++] = new int[1+(INITIAL_CACHE_RECORD_COUNT*CACHE_RECORD_SIZE)]; |
| } |
| public void reset() { |
| fSymbolCharsOffset = 0; |
| fCacheLineCount = 0; |
| fCacheLines[fCacheLineCount++] = new int[1+(INITIAL_CACHE_RECORD_COUNT*CACHE_RECORD_SIZE)]; |
| } |
| // |
| // |
| // |
| public char[] getSymbolChars() { |
| return fSymbolChars; |
| } |
| // |
| // Symbol interfaces |
| // |
| public String createSymbol(int symbolHandle, int startOffset, int entry, int[] entries, int offset) { |
| int slen = fSymbolCharsOffset - startOffset; |
| String str = new String(fSymbolChars, startOffset, slen); |
| try { |
| entries[offset + SymbolCache.INDEX_OFFSET] = symbolHandle; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| throw new RuntimeException("UTL001 untested"); |
| } |
| return str; |
| } |
| public int addSymbolToCache(String str, int slen, int symbolHandle) { |
| int charsOffset = fSymbolCharsOffset; |
| if (slen == 0) // EMPTY_STRING cannot be a legal "symbol" |
| return charsOffset; |
| int strIndex = 0; |
| char ch = str.charAt(strIndex++); |
| try { |
| fSymbolChars[fSymbolCharsOffset] = ch; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| char[] newChars = new char[fSymbolChars.length * 2]; |
| System.arraycopy(fSymbolChars, 0, newChars, 0, fSymbolChars.length); |
| fSymbolChars = newChars; |
| fSymbolChars[fSymbolCharsOffset] = ch; |
| } |
| fSymbolCharsOffset++; |
| int entry = 0; |
| int[] entries = fCacheLines[entry]; |
| int count = entries[0]; |
| int i = 0; |
| int offset = 1; |
| while (true) { |
| if (i == count) |
| break; |
| if (entries[offset + CHAR_OFFSET] != ch) { |
| i++; |
| offset += CACHE_RECORD_SIZE; |
| continue; |
| } |
| if (strIndex == slen) { |
| if (entries[offset + INDEX_OFFSET] != -1) { |
| // How did we miss this during lookup ? |
| throw new RuntimeException("addSymbolToCache"); |
| } |
| entries[offset + INDEX_OFFSET] = symbolHandle; |
| return charsOffset; |
| } |
| ch = str.charAt(strIndex++); |
| try { |
| fSymbolChars[fSymbolCharsOffset] = ch; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| char[] newChars = new char[fSymbolChars.length * 2]; |
| System.arraycopy(fSymbolChars, 0, newChars, 0, fSymbolChars.length); |
| fSymbolChars = newChars; |
| fSymbolChars[fSymbolCharsOffset] = ch; |
| } |
| fSymbolCharsOffset++; |
| entry = entries[offset + NEXT_OFFSET]; |
| try { |
| entries = fCacheLines[entry]; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| if (entry == -1) { |
| entry = fCacheLineCount++; |
| entries[offset + NEXT_OFFSET] = entry; |
| entries = new int[1+(INITIAL_CACHE_RECORD_COUNT*CACHE_RECORD_SIZE)]; |
| try { |
| fCacheLines[entry] = entries; |
| } catch (ArrayIndexOutOfBoundsException ex2) { |
| int[][] newCache = new int[entry * 2][]; |
| System.arraycopy(fCacheLines, 0, newCache, 0, entry); |
| fCacheLines = newCache; |
| fCacheLines[entry] = entries; |
| } |
| } else { |
| entries = fCacheLines[entry]; |
| throw new RuntimeException("UTL001 untested"); |
| } |
| } |
| count = entries[0]; |
| i = 0; |
| offset = 1; |
| } |
| while (true) { |
| entries[0]++; |
| try { |
| entries[offset + CHAR_OFFSET] = ch; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| int newSize = 1 + ((offset - 1) * 2); |
| int[] newEntries = new int[newSize]; |
| System.arraycopy(entries, 0, newEntries, 0, offset); |
| fCacheLines[entry] = entries = newEntries; |
| entries[offset + CHAR_OFFSET] = ch; |
| } |
| if (strIndex == slen) { |
| entries[offset + INDEX_OFFSET] = symbolHandle; |
| entries[offset + NEXT_OFFSET] = -1; |
| break; |
| } |
| entry = fCacheLineCount++; |
| entries[offset + INDEX_OFFSET] = -1; |
| entries[offset + NEXT_OFFSET] = entry; |
| entries = new int[1+(INITIAL_CACHE_RECORD_COUNT*CACHE_RECORD_SIZE)]; |
| try { |
| fCacheLines[entry] = entries; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| int[][] newCache = new int[entry * 2][]; |
| System.arraycopy(fCacheLines, 0, newCache, 0, entry); |
| fCacheLines = newCache; |
| fCacheLines[entry] = entries; |
| } |
| offset = 1; |
| ch = str.charAt(strIndex++); |
| try { |
| fSymbolChars[fSymbolCharsOffset] = ch; |
| } catch (ArrayIndexOutOfBoundsException ex) { |
| char[] newChars = new char[fSymbolChars.length * 2]; |
| System.arraycopy(fSymbolChars, 0, newChars, 0, fSymbolChars.length); |
| fSymbolChars = newChars; |
| fSymbolChars[fSymbolCharsOffset] = ch; |
| } |
| fSymbolCharsOffset++; |
| } |
| return charsOffset; |
| } |
| public void updateCacheLine(int charsOffset, int totalMisses, int length) { |
| //System.err.println("found symbol " + toString(symbolIndex) + " after " + totalMisses + " total misses (" + (totalMisses/length) + " misses per character)."); |
| int entry = 0; |
| int[] entries = fCacheLines[0]; |
| int ch = fSymbolChars[charsOffset++]; |
| int count = entries[0]; |
| int offset = 1 + ((count - 1) * CACHE_RECORD_SIZE); |
| int misses = 0; |
| while (true) { |
| if (ch != entries[offset + CHAR_OFFSET]) { |
| offset -= CACHE_RECORD_SIZE; |
| misses++; |
| continue; |
| } |
| if (misses > 4) { |
| int symIndex = entries[offset + INDEX_OFFSET]; |
| int nextIndex = entries[offset + NEXT_OFFSET]; |
| System.arraycopy(entries, offset + CACHE_RECORD_SIZE, entries, offset, misses * CACHE_RECORD_SIZE); |
| offset = 1 + ((count - 1) * CACHE_RECORD_SIZE); |
| entries[offset + CHAR_OFFSET] = ch; |
| entries[offset + INDEX_OFFSET] = symIndex; |
| entries[offset + NEXT_OFFSET] = nextIndex; |
| } |
| if (--length == 0) |
| break; |
| entry = entries[offset + NEXT_OFFSET]; |
| entries = fCacheLines[entry]; |
| ch = fSymbolChars[charsOffset++]; |
| count = entries[0]; |
| offset = 1 + ((count - 1) * CACHE_RECORD_SIZE); |
| misses = 0; |
| } |
| } |
| } |
