Implemented server.getOfflinePlayers

src/main/java/org/bukkit/craftbukkit/util/DatFileFilter.java

@@ -0,0 +1,10 @@
+package org.bukkit.craftbukkit.util;
+
+import java.io.File;
+import java.io.FilenameFilter;
+
+public class DatFileFilter implements FilenameFilter {
+    public boolean accept(File dir, String name) {
+        return name.endsWith(".dat");
+    }
+}