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Diffstat (limited to '')
| -rw-r--r-- | src/libs/xpcom18a4/java/src/org/mozilla/xpcom/VersionComparator.java | 272 |
1 files changed, 272 insertions, 0 deletions
diff --git a/src/libs/xpcom18a4/java/src/org/mozilla/xpcom/VersionComparator.java b/src/libs/xpcom18a4/java/src/org/mozilla/xpcom/VersionComparator.java new file mode 100644 index 00000000..f9fb1058 --- /dev/null +++ b/src/libs/xpcom18a4/java/src/org/mozilla/xpcom/VersionComparator.java @@ -0,0 +1,272 @@ +/* ***** BEGIN LICENSE BLOCK ***** + * Version: MPL 1.1/GPL 2.0/LGPL 2.1 + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + * + * The Original Code is Java XPCOM Bindings. + * + * The Initial Developer of the Original Code is + * IBM Corporation. + * Portions created by the Initial Developer are Copyright (C) 2005 + * IBM Corporation. All Rights Reserved. + * + * Contributor(s): + * Javier Pedemonte (jhpedemonte@gmail.com) + * + * Alternatively, the contents of this file may be used under the terms of + * either the GNU General Public License Version 2 or later (the "GPL"), or + * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), + * in which case the provisions of the GPL or the LGPL are applicable instead + * of those above. If you wish to allow use of your version of this file only + * under the terms of either the GPL or the LGPL, and not to allow others to + * use your version of this file under the terms of the MPL, indicate your + * decision by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL or the LGPL. If you do not delete + * the provisions above, a recipient may use your version of this file under + * the terms of any one of the MPL, the GPL or the LGPL. + * + * ***** END LICENSE BLOCK ***** */ + +package org.mozilla.xpcom; + +import java.util.Enumeration; +import java.util.StringTokenizer; + +import org.mozilla.interfaces.nsISupports; +/* import org.mozilla.interfaces.nsIVersionComparator; */ + + +/** + * Version strings are dot-separated sequences of version-parts. + * <p> + * A version-part consists of up to four parts, all of which are optional: + * <br><code> + * <number-a><string-b><number-c> + * <string-d (everything else)> + * </code> <p> + * A version-part may also consist of a single asterisk "*" which indicates + * "infinity". + * <p> + * Numbers are base-10, and are zero if left out. + * Strings are compared bytewise. + * <p> + * For additional backwards compatibility, if "string-b" is "+" then + * "number-a" is incremented by 1 and "string-b" becomes "pre". + * <p> <pre> + * 1.0pre1 + * < 1.0pre2 + * < 1.0 == 1.0.0 == 1.0.0.0 + * < 1.1pre == 1.1pre0 == 1.0+ + * < 1.1pre1a + * < 1.1pre1 + * < 1.1pre10a + * < 1.1pre10 + * </pre> + * Although not required by this interface, it is recommended that + * numbers remain within the limits of a signed char, i.e. -127 to 128. + */ +public class VersionComparator implements nsISupports /* implements nsIVersionComparator */ { + + public nsISupports queryInterface(String aIID) { + return Mozilla.queryInterface(this, aIID); + } + + /** + * Compare two version strings + * @param A a version string + * @param B a version string + * @return a value less than 0 if A < B; + * the value 0 if A == B; + * or a value greater than 0 if A > B + */ + public int compare(String A, String B) { + int result; + String a = A, b = B; + + do { + VersionPart va = new VersionPart(); + VersionPart vb = new VersionPart(); + a = parseVersionPart(a, va); + b = parseVersionPart(b, vb); + + result = compareVersionPart(va, vb); + if (result != 0) { + break; + } + } while (a != null || b != null); + + return result; + } + + private class VersionPart { + int numA = 0; + String strB; + int numC = 0; + String extraD; + } + + private static String parseVersionPart(String aVersion, VersionPart result) { + if (aVersion == null || aVersion.length() == 0) { + return aVersion; + } + + StringTokenizer tok = new StringTokenizer(aVersion.trim(), "."); + String part = tok.nextToken(); + + if (part.equals("*")) { + result.numA = Integer.MAX_VALUE; + result.strB = ""; + } else { + VersionPartTokenizer vertok = new VersionPartTokenizer(part); + try { + result.numA = Integer.parseInt(vertok.nextToken()); + } catch (NumberFormatException e) { + // parsing error; default to zero like 'strtol' C function + result.numA = 0; + } + + if (vertok.hasMoreElements()) { + String str = vertok.nextToken(); + + // if part is of type "<num>+" + if (str.charAt(0) == '+') { + result.numA++; + result.strB = "pre"; + } else { + // else if part is of type "<num><alpha>..." + result.strB = str; + + if (vertok.hasMoreTokens()) { + try { + result.numC = Integer.parseInt(vertok.nextToken()); + } catch (NumberFormatException e) { + // parsing error; default to zero like 'strtol' C function + result.numC = 0; + } + if (vertok.hasMoreTokens()) { + result.extraD = vertok.getRemainder(); + } + } + } + } + } + + if (tok.hasMoreTokens()) { + // return everything after "." + return aVersion.substring(part.length() + 1); + } + return null; + } + + private int compareVersionPart(VersionPart va, VersionPart vb) { + int res = compareInt(va.numA, vb.numA); + if (res != 0) { + return res; + } + + res = compareString(va.strB, vb.strB); + if (res != 0) { + return res; + } + + res = compareInt(va.numC, vb.numC); + if (res != 0) { + return res; + } + + return compareString(va.extraD, vb.extraD); + } + + private int compareInt(int n1, int n2) { + return n1 - n2; + } + + private int compareString(String str1, String str2) { + // any string is *before* no string + if (str1 == null) { + return (str2 != null) ? 1 : 0; + } + + if (str2 == null) { + return -1; + } + + return str1.compareTo(str2); + } + +} + +/** + * Specialized tokenizer for Mozilla version strings. A token can + * consist of one of the four sections of a version string: <code> + * <number-a><string-b><number-c> + * <string-d (everything else)></code>. + */ +class VersionPartTokenizer implements Enumeration { + + String part; + + public VersionPartTokenizer(String aPart) { + part = aPart; + } + + public boolean hasMoreElements() { + return part.length() != 0; + } + + public boolean hasMoreTokens() { + return part.length() != 0; + } + + public Object nextElement() { + if (part.matches("[\\+\\-]?[0-9].*")) { + // if string starts with a number... + int index = 0; + if (part.charAt(0) == '+' || part.charAt(0) == '-') { + index = 1; + } + + while (index < part.length() && Character.isDigit(part.charAt(index))) { + index++; + } + + String numPart = part.substring(0, index); + part = part.substring(index); + return numPart; + } else { + // ... or if this is the non-numeric part of version string + int index = 0; + while (index < part.length() && !Character.isDigit(part.charAt(index))) { + index++; + } + + String alphaPart = part.substring(0, index); + part = part.substring(index); + return alphaPart; + } + } + + public String nextToken() { + return (String) nextElement(); + } + + /** + * Returns what remains of the original string, without tokenization. This + * method is useful for getting the <code><string-d (everything else)> + * </code> section of a version string. + * + * @return remaining version string + */ + public String getRemainder() { + return part; + } + +} |