Merge pull request #6753 from eugene7646/release-4.18.0

Potential NPE fix in SU Solr logic (7343)

KeywordSearch/src/org/sleuthkit/autopsy/keywordsearch/Server.java

@@ -671,9 +671,18 @@ private HttpSolrClient configureMultiUserConnection(Case theCase, Index index, S
         "Server.status.failed.msg=Local Solr server did not respond to status request. This may be because the server failed to start or is taking too long to initialize.",})
     synchronized void startLocalSolr(SOLR_VERSION version) throws KeywordSearchModuleException, SolrServerNoPortException, SolrServerException {
         
+        logger.log(Level.INFO, "Starting local Solr " + version + " server"); //NON-NLS
+        if (version == SOLR_VERSION.SOLR8) {
+            localSolrFolder = InstalledFileLocator.getDefault().locate("solr", Server.class.getPackage().getName(), false); //NON-NLS
+        } else {
+            // solr4
+            localSolrFolder = InstalledFileLocator.getDefault().locate("solr4", Server.class.getPackage().getName(), false); //NON-NLS
+        }
+
         if (isLocalSolrRunning()) {
             if (localServerVersion.equals(version)) {
                 // this version of local server is already running
+                logger.log(Level.INFO, "Local Solr " + version + " server is already running"); //NON-NLS
                 return;
             } else {
                 // wrong version of local server is running, stop it
@@ -715,12 +724,10 @@ synchronized void startLocalSolr(SOLR_VERSION version) throws KeywordSearchModul
             try {
                 if (version == SOLR_VERSION.SOLR8) {
                     logger.log(Level.INFO, "Starting Solr 8 server"); //NON-NLS
-                    localSolrFolder = InstalledFileLocator.getDefault().locate("solr", Server.class.getPackage().getName(), false); //NON-NLS
                     curSolrProcess = runLocalSolr8ControlCommand(new ArrayList<>(Arrays.asList("start", "-p", //NON-NLS
                         Integer.toString(localSolrServerPort)))); //NON-NLS
                 } else {
                     // solr4
-                    localSolrFolder = InstalledFileLocator.getDefault().locate("solr4", Server.class.getPackage().getName(), false); //NON-NLS
                     logger.log(Level.INFO, "Starting Solr 4 server"); //NON-NLS
                     curSolrProcess = runLocalSolr4ControlCommand(new ArrayList<>(
                         Arrays.asList("-Dbootstrap_confdir=../solr/configsets/AutopsyConfig/conf", //NON-NLS