new: sort cache series numerically correct when sorting by name

1 files changed, 16 insertions, 0 deletions

diff --git a/main/src/cgeo/geocaching/sorting/NameComparator.java b/main/src/cgeo/geocaching/sorting/NameComparator.java
index d301180..e17a945 100644
--- a/main/src/cgeo/geocaching/sorting/NameComparator.java
+++ b/main/src/cgeo/geocaching/sorting/NameComparator.java
@@ -4,6 +4,8 @@ import cgeo.geocaching.cgCache;
 
 import org.apache.commons.lang3.StringUtils;
 
+import java.util.Scanner;
+
 /**
  * sorts caches by name
  *
@@ -17,6 +19,20 @@ public class NameComparator extends AbstractCacheComparator {
 
     @Override
     protected int compareCaches(cgCache cache1, cgCache cache2) {
+        // if the caches have a common prefix followed by a number, sort by the numerical value
+        // so 2 is before 11, although "11" comes before "2"
+        final String prefix = StringUtils.getCommonPrefix(cache1.name, cache2.name);
+        if (StringUtils.length(prefix) > 0) {
+            final String remaining1 = cache1.name.substring(prefix.length()).trim();
+            if (remaining1.length() > 0 && Character.isDigit(remaining1.charAt(0))) {
+                final String remaining2 = cache2.name.substring(prefix.length()).trim();
+                if (remaining2.length() > 0 && Character.isDigit(remaining2.charAt(0))) {
+                    final Integer number1 = (new Scanner(remaining1)).nextInt();
+                    final Integer number2 = (new Scanner(remaining2)).nextInt();
+                    return number1.compareTo(number2);
+                }
+            }
+        }
         return cache1.name.compareToIgnoreCase(cache2.name);
     }
 }