Adjust mergeDocuments to keep youngest last-modified date of document

collection

source/net/yacy/document/Document.java

@@ -924,7 +924,7 @@ dc_rights
         final Set<String> languages = new HashSet<>();
         double lon = 0.0d, lat = 0.0d;
         boolean indexingDenied = false;
-        Date date = new Date();
+        Date date = null;
         String charset = null;
 
         int mindepth = 999;
@@ -968,7 +968,7 @@ dc_rights
             rss.putAll(doc.getRSS());
             images.putAll(doc.getImages());
             if (doc.lon() != 0.0 && doc.lat() != 0.0) { lon = doc.lon(); lat = doc.lat(); }
-            if (doc.lastModified.before(date)) date = doc.lastModified;
+            if (date == null || doc.lastModified.after(date)) date = doc.lastModified; // set youngest lastModified date from doc collection
             
             if (doc.getDepth() < mindepth) mindepth = doc.getDepth();
             if (doc.dc_language() != null) languages.add(doc.dc_language());

test/java/net/yacy/document/DocumentTest.java

@@ -0,0 +1,98 @@
+/**
+ *  DomainsTest
+ *  part of YaCy
+ *  Copyright 2017 by reger24; https://github.com/reger24
+ *
+ *  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.document;
+
+import java.net.MalformedURLException;
+import java.nio.charset.Charset;
+import java.util.Date;
+import net.yacy.cora.document.id.DigestURL;
+import org.junit.Test;
+import static org.junit.Assert.*;
+
+/**
+ * Unit tests for Document class.
+ */
+public class DocumentTest {
+
+    /**
+     * Test of lastmodified calculation after mergeDocuments method, of class
+     * Document.
+     */
+    @Test
+    public void testMergeDocuments_lastModified() throws MalformedURLException {
+
+        Date lastmodDateMin = new Date(10*1000); // min test date
+        Date lastmodDateMax = new Date(20*1000); // max test date
+
+        DigestURL location = new DigestURL("http://localhost/test.html");
+        String mimeType = "test/html";
+        String charset = Charset.defaultCharset().name();
+        Document[] docs = new Document[2];
+        // prepare simple document with min modified-date
+        docs[0] = new Document(
+                location,
+                mimeType,
+                charset,
+                null,
+                null,
+                null,
+                null, // title
+                null, // author
+                location.getHost(),
+                null,
+                null,
+                0.0d, 0.0d,
+                location.toTokens(),
+                null,
+                null,
+                null,
+                false,
+                lastmodDateMin);
+
+        // prepare simple document with max modified-date
+        docs[1] = new Document(
+                location,
+                mimeType,
+                charset,
+                null,
+                null,
+                null,
+                null, // title
+                null, // author
+                location.getHost(),
+                null,
+                null,
+                0.0d, 0.0d,
+                location.toTokens(),
+                null,
+                null,
+                null,
+                false,
+                lastmodDateMax);
+
+        // get last-modified after merge
+        Document result = Document.mergeDocuments(location, charset, docs);
+
+        // expected to be newest test date
+        assertEquals("merged last-modified Date",lastmodDateMax.getTime(), result.getLastModified().getTime());
+
+    }
+
+}