+/*\r
+ * The Alphanum Algorithm is an improved sorting algorithm for strings\r
+ * containing numbers. Instead of sorting numbers in ASCII order like\r
+ * a standard sort, this algorithm sorts numbers in numeric order.\r
+ *\r
+ * The Alphanum Algorithm is discussed at http://www.DaveKoelle.com\r
+ *\r
+ *\r
+ * This library is free software; you can redistribute it and/or\r
+ * modify it under the terms of the GNU Lesser General Public\r
+ * License as published by the Free Software Foundation; either\r
+ * version 2.1 of the License, or any later version.\r
+ *\r
+ * This library is distributed in the hope that it will be useful,\r
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of\r
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU\r
+ * Lesser General Public License for more details.\r
+ *\r
+ * You should have received a copy of the GNU Lesser General Public\r
+ * License along with this library; if not, write to the Free Software\r
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA\r
+ *\r
+ */\r
+\r
+package com.owncloud.android.datamodel;\r
+import java.util.Comparator;\r
+\r
+/**\r
+ * This is an updated version with enhancements made by Daniel Migowski,\r
+ * Andre Bogus, and David Koelle\r
+ *\r
+ * To convert to use Templates (Java 1.5+):\r
+ * - Change "implements Comparator" to "implements Comparator<String>"\r
+ * - Change "compare(Object o1, Object o2)" to "compare(String s1, String s2)"\r
+ * - Remove the type checking and casting in compare().\r
+ *\r
+ * To use this class:\r
+ * Use the static "sort" method from the java.util.Collections class:\r
+ * Collections.sort(your list, new AlphanumComparator());\r
+ */\r
+public class AlphanumComparator implements Comparator<OCFile>\r
+{\r
+ private final boolean isDigit(char ch)\r
+ {\r
+ return ch >= 48 && ch <= 57;\r
+ }\r
+\r
+ /** Length of string is passed in for improved efficiency (only need to calculate it once) **/\r
+ private final String getChunk(String s, int slength, int marker)\r
+ {\r
+ StringBuilder chunk = new StringBuilder();\r
+ char c = s.charAt(marker);\r
+ chunk.append(c);\r
+ marker++;\r
+ if (isDigit(c))\r
+ {\r
+ while (marker < slength)\r
+ {\r
+ c = s.charAt(marker);\r
+ if (!isDigit(c))\r
+ break;\r
+ chunk.append(c);\r
+ marker++;\r
+ }\r
+ } else\r
+ {\r
+ while (marker < slength)\r
+ {\r
+ c = s.charAt(marker);\r
+ if (isDigit(c))\r
+ break;\r
+ chunk.append(c);\r
+ marker++;\r
+ }\r
+ }\r
+ return chunk.toString();\r
+ }\r
+\r
+ public int compare(OCFile o1, OCFile o2)\r
+ {\r
+ String s1 = (String)o1.getRemotePath().toLowerCase();\r
+ String s2 = (String)o2.getRemotePath().toLowerCase();\r
+\r
+ int thisMarker = 0;\r
+ int thatMarker = 0;\r
+ int s1Length = s1.length();\r
+ int s2Length = s2.length();\r
+\r
+ while (thisMarker < s1Length && thatMarker < s2Length)\r
+ {\r
+ String thisChunk = getChunk(s1, s1Length, thisMarker);\r
+ thisMarker += thisChunk.length();\r
+\r
+ String thatChunk = getChunk(s2, s2Length, thatMarker);\r
+ thatMarker += thatChunk.length();\r
+\r
+ // If both chunks contain numeric characters, sort them numerically\r
+ int result = 0;\r
+ if (isDigit(thisChunk.charAt(0)) && isDigit(thatChunk.charAt(0)))\r
+ {\r
+ // Simple chunk comparison by length.\r
+ int thisChunkLength = thisChunk.length();\r
+ result = thisChunkLength - thatChunk.length();\r
+ // If equal, the first different number counts\r
+ if (result == 0)\r
+ {\r
+ for (int i = 0; i < thisChunkLength; i++)\r
+ {\r
+ result = thisChunk.charAt(i) - thatChunk.charAt(i);\r
+ if (result != 0)\r
+ {\r
+ return result;\r
+ }\r
+ }\r
+ }\r
+ } else\r
+ {\r
+ result = thisChunk.compareTo(thatChunk);\r
+ }\r
+\r
+ if (result != 0)\r
+ return result;\r
+ }\r
+\r
+ return s1Length - s2Length;\r
+ }\r
+}\r