| /* |
| * Copyright (c) 2002, 2004, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package sun.misc; |
| |
| import java.util.Comparator; |
| |
| /** Implements a locale and case insensitive comparator suitable for |
| strings that are known to only contain ASCII characters. Some |
| tables internal to the JDK contain only ASCII data and are using |
| the "generalized" java.lang.String case-insensitive comparator |
| which converts each character to both upper and lower case. */ |
| |
| public class ASCIICaseInsensitiveComparator implements Comparator<String> { |
| public static final Comparator<String> CASE_INSENSITIVE_ORDER = |
| new ASCIICaseInsensitiveComparator(); |
| |
| public int compare(String s1, String s2) { |
| int n1=s1.length(), n2=s2.length(); |
| int minLen = n1 < n2 ? n1 : n2; |
| for (int i=0; i < minLen; i++) { |
| char c1 = s1.charAt(i); |
| char c2 = s2.charAt(i); |
| assert c1 <= '\u007F' && c2 <= '\u007F'; |
| if (c1 != c2) { |
| c1 = (char)toLower(c1); |
| c2 = (char)toLower(c2); |
| if (c1 != c2) { |
| return c1 - c2; |
| } |
| } |
| } |
| return n1 - n2; |
| } |
| |
| /** |
| * A case insensitive hash code method to go with the case insensitive |
| * compare() method. |
| * |
| * Returns a hash code for this ASCII string as if it were lower case. |
| * |
| * returns same answer as:<p> |
| * <code>s.toLowerCase(Locale.US).hashCode();</code><p> |
| * but does not allocate memory (it does NOT have the special |
| * case Turkish rules). |
| * |
| * @param s a String to compute the hashcode on. |
| * @return a hash code value for this object. |
| */ |
| public static int lowerCaseHashCode(String s) { |
| int h = 0; |
| int len = s.length(); |
| |
| for (int i = 0; i < len; i++) { |
| h = 31*h + toLower(s.charAt(i)); |
| } |
| |
| return h; |
| } |
| |
| /* If java.util.regex.ASCII ever becomes public or sun.*, use its code instead:*/ |
| static boolean isLower(int ch) { |
| return ((ch-'a')|('z'-ch)) >= 0; |
| } |
| |
| static boolean isUpper(int ch) { |
| return ((ch-'A')|('Z'-ch)) >= 0; |
| } |
| |
| static int toLower(int ch) { |
| return isUpper(ch) ? (ch + 0x20) : ch; |
| } |
| |
| static int toUpper(int ch) { |
| return isLower(ch) ? (ch - 0x20) : ch; |
| } |
| } |