svn commit: r980192 - /directory/apacheds/branches/apacheds-dnfactory-experiment/core/src/main/java/org/apache/directory/server/core/DNFactory.java

[ka...@apache.org]

Author: kayyagari
Date: Wed Jul 28 20:04:57 2010
New Revision: 980192

URL: http://svn.apache.org/viewvc?rev=980192&view=rev
Log:
o a simple cached DN factory implementation

Added:
    directory/apacheds/branches/apacheds-dnfactory-experiment/core/src/main/java/org/apache/directory/server/core/DNFactory.java

Added: directory/apacheds/branches/apacheds-dnfactory-experiment/core/src/main/java/org/apache/directory/server/core/DNFactory.java
URL: http://svn.apache.org/viewvc/directory/apacheds/branches/apacheds-dnfactory-experiment/core/src/main/java/org/apache/directory/server/core/DNFactory.java?rev=980192&view=auto
==============================================================================
--- directory/apacheds/branches/apacheds-dnfactory-experiment/core/src/main/java/org/apache/directory/server/core/DNFactory.java (added)
+++ directory/apacheds/branches/apacheds-dnfactory-experiment/core/src/main/java/org/apache/directory/server/core/DNFactory.java Wed Jul 28 20:04:57 2010
@@ -0,0 +1,137 @@
+/*
+ *   Licensed to the Apache Software Foundation (ASF) under one
+ *   or more contributor license agreements.  See the NOTICE file
+ *   distributed with this work for additional information
+ *   regarding copyright ownership.  The ASF licenses this file
+ *   to you under the Apache License, Version 2.0 (the
+ *   "License"); you may not use this file except in compliance
+ *   with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *   Unless required by applicable law or agreed to in writing,
+ *   software distributed under the License is distributed on an
+ *   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ *   KIND, either express or implied.  See the License for the
+ *   specific language governing permissions and limitations
+ *   under the License.
+ *
+ */
+
+package org.apache.directory.server.core;
+
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.apache.directory.shared.ldap.exception.LdapInvalidDnException;
+import org.apache.directory.shared.ldap.name.DN;
+import org.apache.directory.shared.ldap.schema.SchemaManager;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+
+/**
+ * A DN factory.
+ *
+ * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
+ */
+public class DNFactory
+{
+
+    /** a map of <DN-upName, DN> tuples */
+    // NOTE: currently a map is used, will eventually be replaced with ehCache if thie experiment succeeds
+    private static final Map<String, DN> DN_CACHE = new ConcurrentHashMap<String, DN>();
+
+    private static final Logger LOG = LoggerFactory.getLogger( DNFactory.class );
+
+    // stat counters
+    private static int hitCount = 0;
+    private static int missCount = 0;
+
+
+    /**
+     * searches the cache first for a possible DN value based on the given 'upName' match.
+     * If a DN is present in the cache will return it (after normalizing if required)
+     * otherwise will create a new DN instance and stores in the cache before returning it
+     * 
+     * Note that the DN cache is maintained by using user provided DN name as key
+     *
+     * @param dn the upName of the DN
+     * @param schemaManager the schema manager (optional)
+     * @return a DN
+     * @throws LdapInvalidDnException
+     */
+    public static DN create( String dn, SchemaManager schemaManager ) throws LdapInvalidDnException
+    {
+        if ( dn == null || dn.trim().length() == 0 )
+        {
+            return null;
+        }
+
+        DN cachedDN = DN_CACHE.get( dn );
+
+        if ( cachedDN == null )
+        {
+            LOG.debug( "DN {} not found in the cache, creating", dn );
+
+            cachedDN = new DN( dn, schemaManager );
+
+            DN_CACHE.put( dn, cachedDN );
+            missCount++;
+        }
+        else
+        {
+            if ( !cachedDN.isNormalized() && ( schemaManager != null ) )
+            {
+                cachedDN.normalize( schemaManager.getNormalizerMapping() );
+            }
+
+            hitCount++;
+        }
+
+        LOG.debug( "DN {} found in the cache", dn );
+        System.out.println( "DN cache hit - " + hitCount + ", miss - " + missCount + " and is normalized = "
+            + cachedDN.isNormalized() );
+        return cachedDN;
+    }
+
+
+    public static DN create( String... upRdns ) throws LdapInvalidDnException
+    {
+        return create( null, upRdns );
+    }
+
+
+    public static DN create( SchemaManager schemaManager, String... upRdns ) throws LdapInvalidDnException
+    {
+        StringBuilder sb = new StringBuilder();
+        for ( String s : upRdns )
+        {
+            sb.append( s ).append( ',' );
+        }
+
+        String dn = sb.toString();
+        dn = dn.substring( 0, dn.length() - 1 );
+        return create( dn, schemaManager );
+    }
+
+
+    public static DN create( DN dn ) throws LdapInvalidDnException
+    {
+        return create( dn.getName(), null );
+    }
+
+
+    public static DN create( DN dn, SchemaManager schemaManager ) throws LdapInvalidDnException
+    {
+        return create( dn.getName(), schemaManager );
+    }
+
+
+    public static DN create( String dn ) throws LdapInvalidDnException
+    {
+        return create( dn, null );
+    }
+
+}