AsciiUtil.java

/*
 * Copyright (c) 2010, 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.
 */

/*
 *******************************************************************************
 * Copyright (C) 2009, International Business Machines Corporation and         *
 * others. All Rights Reserved.                                                *
 *******************************************************************************
 */
package sun.util.locale;

public final class AsciiUtil {
    public static boolean caseIgnoreMatch(String s1, String s2) {
        if (s1 == s2) {
            return true;
        }
        int len = s1.length();
        if (len != s2.length()) {
            return false;
        }
        int i = 0;
        while (i < len) {
            char c1 = s1.charAt(i);
            char c2 = s2.charAt(i);
            if (c1 != c2 && toLower(c1) != toLower(c2)) {
                break;
            }
            i++;
        }
        return (i == len);
    }

    public static int caseIgnoreCompare(String s1, String s2) {
        if (s1 == s2) {
            return 0;
        }
        return AsciiUtil.toLowerString(s1).compareTo(AsciiUtil.toLowerString(s2));
    }


    public static char toUpper(char c) {
        if (c >= 'a' && c <= 'z') {
            c -= 0x20;
        }
        return c;
    }

    public static char toLower(char c) {
        if (c >= 'A' && c <= 'Z') {
            c += 0x20;
        }
        return c;
    }

    public static String toLowerString(String s) {
        int idx = 0;
        for (; idx < s.length(); idx++) {
            char c = s.charAt(idx);
            if (c >= 'A' && c <= 'Z') {
                break;
            }
        }
        if (idx == s.length()) {
            return s;
        }
        StringBuilder buf = new StringBuilder(s.substring(0, idx));
        for (; idx < s.length(); idx++) {
            buf.append(toLower(s.charAt(idx)));
        }
        return buf.toString();
    }

    public static String toUpperString(String s) {
        int idx = 0;
        for (; idx < s.length(); idx++) {
            char c = s.charAt(idx);
            if (c >= 'a' && c <= 'z') {
                break;
            }
        }
        if (idx == s.length()) {
            return s;
        }
        StringBuilder buf = new StringBuilder(s.substring(0, idx));
        for (; idx < s.length(); idx++) {
            buf.append(toUpper(s.charAt(idx)));
        }
        return buf.toString();
    }

    public static String toTitleString(String s) {
        if (s.length() == 0) {
            return s;
        }
        int idx = 0;
        char c = s.charAt(idx);
        if (!(c >= 'a' && c <= 'z')) {
            for (idx = 1; idx < s.length(); idx++) {
                if (c >= 'A' && c <= 'Z') {
                    break;
                }
            }
        }
        if (idx == s.length()) {
            return s;
        }
        StringBuilder buf = new StringBuilder(s.substring(0, idx));
        if (idx == 0) {
            buf.append(toUpper(s.charAt(idx)));
            idx++;
        }
        for (; idx < s.length(); idx++) {
            buf.append(toLower(s.charAt(idx)));
        }
        return buf.toString();
    }

    public static boolean isAlpha(char c) {
        return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
    }

    public static boolean isAlphaString(String s) {
        boolean b = true;
        for (int i = 0; i < s.length(); i++) {
            if (!isAlpha(s.charAt(i))) {
                b = false;
                break;
            }
        }
        return b;
    }

    public static boolean isNumeric(char c) {
        return (c >= '0' && c <= '9');
    }

    public static boolean isNumericString(String s) {
        boolean b = true;
        for (int i = 0; i < s.length(); i++) {
            if (!isNumeric(s.charAt(i))) {
                b = false;
                break;
            }
        }
        return b;
    }

    public static boolean isAlphaNumeric(char c) {
        return isAlpha(c) || isNumeric(c);
    }

    public static boolean isAlphaNumericString(String s) {
        boolean b = true;
        for (int i = 0; i < s.length(); i++) {
            if (!isAlphaNumeric(s.charAt(i))) {
                b = false;
                break;
            }
        }
        return b;
    }

    public static class CaseInsensitiveKey {
        private String _key;
        private int _hash;

        public CaseInsensitiveKey(String key) {
            _key = key;
            _hash = AsciiUtil.toLowerString(key).hashCode();
        }

        public boolean equals(Object o) {
            if (this == o) {
                return true;
            }
            if (o instanceof CaseInsensitiveKey) {
                return AsciiUtil.caseIgnoreMatch(_key, ((CaseInsensitiveKey)o)._key);
            }
            return false;
        }

        public int hashCode() {
            return _hash;
        }
    }
}