added new score comparator

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@7888 6c8d7289-2bf4-0310-a012-ef5d649a1542

source/net/yacy/cora/ranking/ScoreComparator.java

@@ -0,0 +1,57 @@
+/**
+ *  ScoreComparator
+ *  Copyright 2011 by Michael Peter Christen, mc@yacy.net, Frankfurt am Main, Germany
+ *  First released 23.08.2011 at http://yacy.net
+ *
+ *  $LastChangedDate: 2011-03-08 02:51:51 +0100 (Di, 08 Mrz 2011) $
+ *  $LastChangedRevision: 7567 $
+ *  $LastChangedBy: low012 $
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with this program in the file lgpl21.txt
+ *  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.yacy.cora.ranking;
+
+import java.util.Comparator;
+
+import net.yacy.cora.storage.ScoreMap;
+
+public class ScoreComparator<E extends Comparable<E>> implements Comparator<E>
+{
+    private final ScoreMap<E> scoreMap;
+    private final boolean reverse;
+
+    public ScoreComparator(final ScoreMap<E> scoreMap, final boolean reverse) {
+        this.scoreMap = scoreMap;
+        this.reverse = reverse;
+    }
+
+    @Override
+    public int compare(final E arg0, final E arg1) {
+        if ( arg0.equals(arg1) ) {
+            return 0;
+        }
+        final int i0 = this.scoreMap.get(arg0);
+        final int i1 = this.scoreMap.get(arg1);
+        if ( i0 < i1 ) {
+            return this.reverse ? 1 : -1;
+        }
+        if ( i0 > i1 ) {
+            return this.reverse ? -1 : 1;
+        }
+        return arg0.compareTo(arg1);
+    }
+
+}