broke out the object cache functionality; generalized ReadOnlyVector;

finally implemented background sweeps of unreferenced cache objects;
anonymous user, when viewing profiles, now sees them as if all "privacy"
flags were switched on

src/com/silverwrist/util/collections/ReadOnlyVector.java

@@ -0,0 +1,72 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.util.collections;
+
+import java.util.*;
+
+public class ReadOnlyVector extends AbstractList
+{
+  /*--------------------------------------------------------------------------------
+   * Attributes
+   *--------------------------------------------------------------------------------
+   */
+
+  private Vector my_vec;  // local vector
+
+  /*--------------------------------------------------------------------------------
+   * Constructor
+   *--------------------------------------------------------------------------------
+   */
+
+  public ReadOnlyVector(Vector vec)
+  {
+    my_vec = vec;
+    my_vec.trimToSize();
+
+  } // end constructor
+
+  /*--------------------------------------------------------------------------------
+   * finalize() method
+   *--------------------------------------------------------------------------------
+   */
+
+  protected void finalize() throws Throwable
+  {
+    my_vec = null;
+    super.finalize();
+
+  } // end finalize
+
+  /*--------------------------------------------------------------------------------
+   * Implementations from superclass AbstractList
+   *--------------------------------------------------------------------------------
+   */
+
+  public Object get(int index)
+  {
+    return my_vec.elementAt(index);
+
+  } // end get
+
+  public int size()
+  {
+    return my_vec.size();
+
+  } // end size
+
+} // end class ReadOnlyVector

src/com/silverwrist/util/rcache/ReferenceCache.java

@@ -0,0 +1,162 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.util.rcache;
+
+import java.util.*;
+import com.silverwrist.util.collections.*;
+
+public class ReferenceCache
+{
+  /*--------------------------------------------------------------------------------
+   * Attributes
+   *--------------------------------------------------------------------------------
+   */
+
+  private HashMap the_data;
+
+  /*--------------------------------------------------------------------------------
+   * Constructor
+   *--------------------------------------------------------------------------------
+   */
+
+  public ReferenceCache()
+  {
+    the_data = new HashMap();
+
+  } // end constructor
+
+  /*--------------------------------------------------------------------------------
+   * External operations
+   *--------------------------------------------------------------------------------
+   */
+
+  public synchronized ReferencedData get(Object key)
+  {
+    ReferencedData rc = (ReferencedData)(the_data.get(key));
+    if (rc!=null)
+      rc.rd_addRef();
+    return rc;
+
+  } // end get
+
+  public synchronized ReferencedData getOrCreate(Object key, ReferencedDataBuilder builder)
+      throws ReferencedDataBuilderException
+  {
+    ReferencedData rc = (ReferencedData)(the_data.get(key));
+    if (rc==null)
+    { // use the builder to build one
+      rc = builder.build(key);
+      if (rc!=null)
+	the_data.put(key,rc);
+
+    } // end if
+    else  // just add a reference
+      rc.rd_addRef();
+
+    return rc;
+
+  } // end getOrCreate
+
+  public void register(ReferencedData data)
+  {
+    Object key = data.rd_getKey();
+
+    synchronized (this)
+    { // see if it's in the cache, if not, add it
+      if (the_data.get(key)!=null)
+	throw new ReferenceCacheException("object already in cache",key);
+
+      // dump it in the object cache
+      the_data.put(key,data);
+
+    } // end synchronized block
+    
+  } // end register
+
+  public synchronized void detach(Object key)
+  {
+    the_data.remove(key);
+
+  } // end detach
+
+  public void sweep()
+  {
+    int count = 0;
+
+    synchronized (this)
+    { // bail out early if possible
+      if (the_data.size()==0)
+	return;
+
+      // provide a storage bin for all keys we decide to 86
+      Object keyzap[] = new Object[the_data.size()];
+      Iterator it = the_data.values().iterator();
+
+      while (it.hasNext())
+      { // check each value we contain in turn
+	ReferencedData rd = (ReferencedData)(it.next());
+	if (rd.rd_unreferenced())
+	  keyzap[count++] = rd.rd_getKey();
+
+      } // end while
+
+      for (int i=0; i<count; i++)
+	the_data.remove(keyzap[i]);
+
+    } // end synchronized block
+
+  } // end sweep
+
+  public List sweepReturn()
+  {
+    Vector rc = new Vector();
+    int count = 0;
+
+    synchronized (this)
+    { // bail out early if possible
+      if (the_data.size()>0)
+      { // provide a storage bin for all keys we decide to 86
+	Object keyzap[] = new Object[the_data.size()];
+	Iterator it = the_data.values().iterator();
+
+	while (it.hasNext())
+	{ // check each value we contain in turn
+	  ReferencedData rd = (ReferencedData)(it.next());
+	  if (rd.rd_unreferenced())
+	    keyzap[count++] = rd.rd_getKey();
+	  else
+	  { // add another reference and tack it onto the list
+	    rd.rd_addRef();
+	    rc.add(rd);
+
+	  } // end else
+
+	} // end while
+
+	for (int i=0; i<count; i++)
+	  the_data.remove(keyzap[i]);
+
+      } // end if
+
+    } // end synchronized block
+
+    return new ReadOnlyVector(rc);
+
+  } // end sweepReturn
+
+} // end ReferenceCache

src/com/silverwrist/util/rcache/ReferenceCacheException.java

@@ -0,0 +1,52 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.util.rcache;
+
+public class ReferenceCacheException extends RuntimeException
+{
+  /*--------------------------------------------------------------------------------
+   * Attributes
+   *--------------------------------------------------------------------------------
+   */
+
+  private Object keyval;
+
+  /*--------------------------------------------------------------------------------
+   * Constructor
+   *--------------------------------------------------------------------------------
+   */
+
+  public ReferenceCacheException(String msg, Object keyval)
+  {
+    super("[keyval " + keyval.toString() + "]: " + msg);
+    this.keyval = keyval;
+
+  } // end constructor
+
+  /*--------------------------------------------------------------------------------
+   * External operations
+   *--------------------------------------------------------------------------------
+   */
+
+  public Object getKeyVal()
+  {
+    return keyval;
+
+  } // end getKeyVal
+
+} // end class ReferenceCacheException

src/com/silverwrist/util/rcache/ReferencedData.java

@@ -0,0 +1,30 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.util.rcache;
+
+public interface ReferencedData
+{
+  public abstract int rd_addRef();
+
+  public abstract int rd_release();
+
+  public abstract boolean rd_unreferenced();
+
+  public abstract Object rd_getKey();
+
+} // end interface ReferencedData

src/com/silverwrist/util/rcache/ReferencedDataBuilder.java

@@ -0,0 +1,24 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.util.rcache;
+
+public interface ReferencedDataBuilder
+{
+  public abstract ReferencedData build(Object key) throws ReferencedDataBuilderException;
+
+} // end interface ReferencedDataBuilder

src/com/silverwrist/util/rcache/ReferencedDataBuilderException.java

@@ -0,0 +1,52 @@
+/*
+ * The contents of this file are subject to the Mozilla Public License Version 1.1
+ * (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.mozilla.org/MPL/>.
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
+ * WARRANTY OF ANY KIND, either express or implied. See the License for the specific
+ * language governing rights and limitations under the License.
+ * 
+ * The Original Code is the Venice Web Communities System.
+ * 
+ * The Initial Developer of the Original Code is Eric J. Bowersox <erbo@silcom.com>,
+ * for Silverwrist Design Studios.  Portions created by Eric J. Bowersox are
+ * Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios.  All Rights Reserved.
+ * 
+ * Contributor(s): 
+ */
+package com.silverwrist.util.rcache;
+
+public class ReferencedDataBuilderException extends Exception
+{
+  /*--------------------------------------------------------------------------------
+   * Attributes
+   *--------------------------------------------------------------------------------
+   */
+
+  private Exception target;
+
+  /*--------------------------------------------------------------------------------
+   * Constructors
+   *--------------------------------------------------------------------------------
+   */
+
+  public ReferencedDataBuilderException(Exception target)
+  {
+    super("Error building new object: " + target.getMessage());
+    this.target = target;
+
+  } // end constructor
+
+  /*--------------------------------------------------------------------------------
+   * External operations
+   *--------------------------------------------------------------------------------
+   */
+
+  public Exception getTarget()
+  {
+    return target;
+
+  } // end getTarget
+
+} // end class ReferencedDataBuilderException