enable use of solrcore.properties for property substitution of solrconfig.xml

- move setting of system property solr.directoryFactory=solr.MMapDirectoryFactory to solrcore.properties
- add check of os.arch for 64bit system, if it fails use default/solrcore.x86.properties (if exists) as solrcore.properties
 
reason: on 32bit MMapDirectoryFactory may fail with.....
Caused by: java.io.IOException: Map failed
	at sun.nio.ch.FileChannelImpl.map(FileChannelImpl.java:849)
	at org.apache.lucene.store.MMapDirectory.map(MMapDirectory.java:283)

defaults/solr/solrcore.properties

@@ -0,0 +1,11 @@
+## Solr solrconfig.xml System property substitution
+##
+## This is the default property file for 64bit system architectures
+##
+## depending on system architecture one default property file is copied to core/conf directory
+## is system architecture is 64bit   property file      solrcore.properties           is copied to core/conf/solrcore.properties
+## otherwise if exists               property file      solrcore.x86.properties       is copied to core/conf/solrcore.properties
+#
+# The DirectoryFactory to use for indexes.
+# Default for 32bit systems is solr.NRTCachingDirectoryFactory, for 64bit systems solr.MMapDirectoryFactory is recommended
+solr.directoryFactory=solr.MMapDirectoryFactory

defaults/solr/solrcore.x86.properties

@@ -0,0 +1,11 @@
+## Solr solrconfig.xml System property substitution
+##
+## This is the property file for 32 bit systems
+##
+## depending on system architecture one default property file is copied to core/conf directory
+## is system architecture is 64bit   property file      solrcore.properties           is copied to core/conf/solrcore.properties
+## otherwise if exists               property file      solrcore.x86.properties       is copied to core/conf/solrcore.properties
+#
+# The DirectoryFactory to use for indexes.
+# Default for 32bit systems is solr.NRTCachingDirectoryFactory, for 64bit systems solr.MMapDirectoryFactory is recommended
+solr.directoryFactory=solr.NRTCachingDirectoryFactory

source/net/yacy/cora/federate/solr/instance/EmbeddedInstance.java

@@ -39,7 +39,7 @@ import com.google.common.io.Files;
 public class EmbeddedInstance implements SolrInstance {
     
     private final static String[] confFiles = {"solrconfig.xml", "schema.xml", "stopwords.txt", "synonyms.txt", "protwords.txt", "currency.xml", "elevate.xml", "xslt/example.xsl", "xslt/json.xsl", "lang/"};
-
+                                              // additional a optional   solrcore.properties     (or solrcore.x86.properties for 32bit systems is copied
     private CoreContainer coreContainer;
     private String defaultCoreName;
     private SolrCore defaultCore;
@@ -92,7 +92,7 @@ public class EmbeddedInstance implements SolrInstance {
             throw new IOException("cannot get the default core; available = " + MemoryControl.available() + ", free = " + MemoryControl.free());
         }
         this.defaultCoreServer = new EmbeddedSolrServer(this.coreContainer, this.defaultCoreName);
-        
+
         // initialize core cache
         this.cores = new ConcurrentHashMap<String, SolrCore>();
         this.cores.put(this.defaultCoreName, this.defaultCore);
@@ -129,13 +129,37 @@ public class EmbeddedInstance implements SolrInstance {
             } else {
                 target = new File(conf, cf);
                 target.getParentFile().mkdirs();
-                try {
+                try {                                       
                     Files.copy(source, target);
                 } catch (IOException e) {
                     e.printStackTrace();
                 }
             }
         }
+        
+        // copy the solrcore.properties
+        // for 32bit systems (os.arch name not containing '64') take the solrcore.x86.properties as solrcore.properties if exists
+        String os = System.getProperty("os.arch");            
+        if (os.contains("64")) {
+            source = new File(solr_config, "solrcore.properties");
+        } else {
+            source = new File(solr_config, "solrcore.x86.properties");
+            if (source.exists()) {
+                source = new File(solr_config, "solrcore.properties");
+            }
+        }
+        // solr alwasy reads the solrcore.properties file if exists in core/conf directory
+        target = new File(conf, "solrcore.properties");
+
+        if (source.exists()) {
+            try {
+                Files.copy(source, target);
+                Log.logFine("initializeCoreConf", "overwrite " + target.getAbsolutePath() + " with " + source.getAbsolutePath());
+            } catch (IOException ex) {
+                ex.printStackTrace();
+            }
+        }
+      
     }
     
     public File getContainerPath() {

source/net/yacy/search/index/Fulltext.java

@@ -328,9 +328,9 @@ public final class Fulltext {
     
     public URIMetadataNode getMetadata(WeakPriorityBlockingQueue.Element<WordReferenceVars> element) {
         if (element == null) return null;
-        WordReferenceVars wre = element.getElement();
-        long weight = element.getWeight();
+        WordReferenceVars wre = element.getElement();        
         if (wre == null) return null; // all time was already wasted in takeRWI to get another element
+        long weight = element.getWeight();
         URIMetadataNode node = getMetadata(wre.urlhash(), wre, weight);
         return node;
     }
@@ -612,7 +612,7 @@ public final class Fulltext {
         if (urlHash == null) return null;
         String reason = (String) this.getDefaultConnector().getFieldById(urlHash, CollectionSchema.failreason_s.getSolrFieldName());
         if (reason == null) return null;
-        return reason == null ? null : reason.length() == 0 ? null : reason;
+        return reason.length() == 0 ? null : reason;
     }
     
     public List<File> dumpFiles() {

source/net/yacy/yacy.java

@@ -622,9 +622,8 @@ public final class yacy {
 	        if (OS.isWindows) headless = false;
 	        if (args.length >= 1 && args[0].toLowerCase().equals("-gui")) headless = false;
 	        System.setProperty("java.awt.headless", headless ? "true" : "false");
-            System.setProperty("java.net.preferIPv4Stack", "true");
-            System.setProperty("solr.directoryFactory","solr.MMapDirectoryFactory"); // should prevent ClosedChannelException
-
+                System.setProperty("java.net.preferIPv4Stack", "true");
+           
 	        String s = ""; for (final String a: args) s += a + " ";
 	        yacyRelease.startParameter = s.trim();