SOLR-1184: Add option to not reopen readers

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@781716 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -491,6 +491,10 @@ Other Changes
 
 36. SOLR-458: Add equals and hashCode methods to NamedList (Stefan Rinner, shalin) 
 
+37. SOLR-1184: Add option in solrconfig to open a new IndexReader rather than
+    using reopen. Done mainly as a fail-safe in the case that a user runs into
+    a reopen bug/issue.  (Mark Miller)
+
 Build
 ----------------------
  1. SOLR-776: Added in ability to sign artifacts via Ant for releases (gsingers)

example/solr/conf/solrconfig.xml

@@ -113,7 +113,12 @@
          This is not needed if lock type is 'none' or 'single'
      -->
     <unlockOnStartup>false</unlockOnStartup>
-
+    
+    <!-- If true, IndexReaders will be reopened (often more efficient) instead
+         of closed and then opened.
+    -->
+    <reopenReaders>true</reopenReaders>
+	  
     <!--
         Custom deletion policies can specified here. The class must
         implement org.apache.lucene.index.IndexDeletionPolicy.

src/java/org/apache/solr/core/SolrConfig.java

@@ -116,6 +116,7 @@ public class SolrConfig extends Config {
     super(loader, name, is, "/config/");
     defaultIndexConfig = new SolrIndexConfig(this, null, null);
     mainIndexConfig = new SolrIndexConfig(this, "mainIndex", defaultIndexConfig);
+    reopenReaders = getBool("mainIndex/reopenReaders", true);
     
     booleanQueryMaxClauseCount = getInt("query/maxBooleanClauses", BooleanQuery.getMaxClauseCount());
     filtOptEnabled = getBool("query/boolTofilterOptimizer/@enabled", false);
@@ -188,6 +189,7 @@ public class SolrConfig extends Config {
   public final int queryResultWindowSize;
   public final int queryResultMaxDocsCached;
   public final boolean enableLazyFieldLoading;
+  public final boolean reopenReaders;
   // DocSet
   public final float hashSetInverseLoadFactor;
   public final int hashDocSetMaxSize;

src/java/org/apache/solr/core/SolrCore.java

@@ -1055,7 +1055,7 @@ public final class SolrCore implements SolrInfoMBean {
       String newIndexDir = getNewIndexDir();
       if (newestSearcher != null) {
         IndexReader currentReader = newestSearcher.get().getReader();
-        if(new File(getIndexDir()).getCanonicalFile().equals(new File(newIndexDir).getCanonicalFile()))  {
+        if(solrConfig.reopenReaders && new File(getIndexDir()).getCanonicalFile().equals(new File(newIndexDir).getCanonicalFile()))  {
           IndexReader newReader = currentReader.reopen();
 
           if(newReader == currentReader) {