Adding missing class LuceneIndexFactory.java NIHVIVO-1143

webapp/src/edu/cornell/mannlib/vitro/webapp/search/lucene/LuceneIndexFactory.java

@@ -0,0 +1,97 @@
+package edu.cornell.mannlib.vitro.webapp.search.lucene;
+
+import java.io.IOException;
+import java.util.List;
+
+import javax.servlet.ServletContext;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.lucene.search.IndexSearcher;
+import org.apache.lucene.store.Directory;
+import org.apache.lucene.store.FSDirectory;
+
+import edu.cornell.mannlib.vitro.webapp.search.SearchException;
+
+public class LuceneIndexFactory {
+    
+	IndexSearcher searcher = null;	
+	private static final Log log = LogFactory.getLog(LuceneIndexFactory.class.getName());
+
+	public static final String LUCENE_INDEX_FACTORY= "LuceneIndexFactory";
+	
+	/**
+	 * Get a lucene IndexSearch. This may return null.
+	 */
+    public static IndexSearcher getIndexSearcher( ServletContext context){    	
+    	return getLuceneIndexFactoryFromContext(context).innerGetIndexSearcher(context);    	
+    }
+    
+    public static LuceneIndexFactory getLuceneIndexFactoryFromContext(ServletContext context){
+        Object obj = context.getAttribute(LUCENE_INDEX_FACTORY);
+        if( obj == null ){
+            setup(context);
+            obj = context.getAttribute(LUCENE_INDEX_FACTORY);
+        }
+        if( obj == null ){
+            log.error("cannot get LuceneIndexFactory from context.  Search is not setup correctly");
+            return null;
+        }
+        if( ! (obj instanceof LuceneIndexFactory)){
+            log.error("LuceneIndexFactory in context was not of correct type. Expected " + LuceneIndexFactory.class.getName() 
+                    + " found " + obj.getClass().getName() + " Search is not setup correctly");
+            return null;
+        }        
+        return (LuceneIndexFactory)obj;
+    }
+    
+    
+    public static void setup(ServletContext context){
+        LuceneIndexFactory lif = (LuceneIndexFactory)context.getAttribute(LuceneIndexFactory.LUCENE_INDEX_FACTORY);
+        if( lif == null ){
+            context.setAttribute(LuceneIndexFactory.LUCENE_INDEX_FACTORY, new LuceneIndexFactory());
+        }   
+    }   
+        
+    /**
+     * This method can be used to force the LuceneIndexFactory to return a new IndexSearcher.
+     * This could be useful if the index was rebult in a different directory on the file system.
+     */
+    public synchronized void forceNewIndexSearcher(){
+        searcher = null;
+    }
+    
+	private synchronized IndexSearcher innerGetIndexSearcher(ServletContext context) {
+		if (searcher == null ) {	    
+			String indexDir = getIndexDir( context );
+			if( indexDir != null ){
+				try {
+					Directory fsDir = FSDirectory.getDirectory(indexDir);
+					searcher = new IndexSearcher(fsDir);
+				} catch (IOException e) {
+					log.error("could not make indexSearcher " + e);
+					log.error("It is likely that you have not made a directory for the lucene index.  "
+								+ "Create the directory indicated in the error and set permissions/ownership so"
+								+ " that the tomcat server can read and write to it.");
+				}		
+			}else{
+			    log.error("Could not create IndexSearcher because index directory was null. It may be that the LucenSetup.indexDir is " +
+			    		" not set in your deploy.properties file.");
+			}
+	    }		
+		return searcher;
+	}
+		
+	private String getIndexDir(ServletContext servletContext){
+		Object obj = servletContext.getAttribute(LuceneSetup.INDEX_DIR);
+		if (obj == null ){
+			log.error("could not find " + LuceneSetup.INDEX_DIR + " in context. Search is not configured correctly.");
+			return null;
+		}else if ( !(obj instanceof String) ){
+			log.error( LuceneSetup.INDEX_DIR + " from context was not a String. Search is not configured correctly.");
+			return null;
+		}else
+			return (String) obj;
+	}
+		
+}