Author: knopp
Date: Thu Jul 12 08:14:59 2007
New Revision: 555654
URL: http://svn.apache.org/viewvc?view=rev&rev=555654
Log:
WICKET-736 - Documentation improvement
Modified:
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/DiskPageStore.java
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/FileChannelPool.java
Modified:
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/DiskPageStore.java
URL:
http://svn.apache.org/viewvc/incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/DiskPageStore.java?view=diff&rev=555654&r1=555653&r2=555654
==============================================================================
---
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/DiskPageStore.java
(original)
+++
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/DiskPageStore.java
Thu Jul 12 08:14:59 2007
@@ -39,7 +39,7 @@
import org.slf4j.LoggerFactory;
/**
- * [EMAIL PROTECTED] IPageStore} implementation that stores the serialized
page grouped in
+ * [EMAIL PROTECTED] IPageStore} implementation that stores the serialized
pages grouped in
* a single file per pagemap.
* <p>
* This store was designed to overcome the problems of [EMAIL PROTECTED]
FilePageStore}
@@ -53,6 +53,11 @@
*/
public class DiskPageStore extends AbstractPageStore
{
+ /**
+ * Each PageMap is represented by this class.
+ *
+ * @author Matej Knopp
+ */
protected static class PageMapEntry
{
private String pageMapName;
@@ -60,7 +65,7 @@
private PageWindowManager manager;
/**
- * @return
+ * @return the name of pagemap
*/
public String getPageMapName()
{
@@ -68,7 +73,7 @@
}
/**
- * @return
+ * @return path of file that contains serialized pages in this
pagemap
*/
public String getFileName()
{
@@ -76,7 +81,8 @@
}
/**
- * @return
+ * @return manager that maintains information about pages
inside the
+ * file
*/
public PageWindowManager getManager()
{
@@ -84,13 +90,18 @@
}
}
+ /**
+ * Represents a session,
+ *
+ * @author Matej Knopp
+ */
protected class SessionEntry
{
private String sessionId;
private List pageMapEntryList = new ArrayList();
/**
- * @return
+ * @return session id
*/
public String getSessionId()
{
@@ -98,7 +109,7 @@
}
/**
- * @return
+ * @return summed size of all pagemap files
*/
public int getTotalSize()
{
@@ -115,14 +126,18 @@
}
/**
- * @return
+ * @return list of [EMAIL PROTECTED] PageMapEntry} for this
session
*/
- public List getPageMapEntryList()
+ public List /* <PageMapEntry> */getPageMapEntryList()
{
return Collections.unmodifiableList(pageMapEntryList);
}
/**
+ * Returns a [EMAIL PROTECTED] PageMapEntry} for specified
pagemap. If the create
+ * attribute is set and the pagemap does not exist, new
+ * [EMAIL PROTECTED] PageMapEntry} will be created.
+ *
* @param pageMapName
* @param create
* @return
@@ -151,6 +166,11 @@
return result;
}
+ /**
+ * Removes the pagemap entry and deletes the file.
+ *
+ * @param entry
+ */
private void removePageMapEntry(PageMapEntry entry)
{
fileChannelPool.closeAndDeleteFileChannel(entry.fileName);
@@ -158,6 +178,8 @@
}
/**
+ * Removes the specified pagemap and deletes the file.
+ *
* @param pageMapName
*/
public synchronized void removePageMap(String pageMapName)
@@ -170,26 +192,38 @@
}
/**
+ * Saves the serialized page to appropriate pagemap file.
+ *
* @param page
*/
public synchronized void savePage(SerializedPage page)
{
+ // only save page that has some data
if (page.getData() != null)
{
PageMapEntry entry =
getPageMapEntry(page.getPageMapName(), true);
+
+ // allocate window for page
PageWindow window =
entry.manager.createPageWindow(page.getPageId(), page
.getVersionNumber(),
page.getAjaxVersionNumber(), page.getData().length);
+
+ // remove the entry and add it to the end of
entry list (to mark
+ // it as last accessed(
pageMapEntryList.remove(entry);
pageMapEntryList.add(entry);
+ // if we exceeded maximum session size, try to
remove as many
+ // pagemap as necessary and possible
while (getTotalSize() > getMaxSizePerSession()
&& pageMapEntryList.size() > 1)
{
removePageMapEntry((PageMapEntry)pageMapEntryList.get(0));
}
+ // take the filechannel from the pool
FileChannel channel =
fileChannelPool.getFileChannel(entry.fileName, true);
try
{
+ // write the content
channel.write(ByteBuffer.wrap(page.getData()), window.getFilePartOffset());
}
catch (IOException e)
@@ -198,12 +232,14 @@
}
finally
{
+ // return the "borrowed" file channel
fileChannelPool.returnFileChannel(channel);
}
}
}
/**
+ * Removes the page from pagemap file.
*
* @param pageMapName
* @param pageId
@@ -218,6 +254,8 @@
}
/**
+ * Loads the part of pagemap file specified by the given
PageWindow.
+ *
* @param window
* @param pageMapFileName
* @return
@@ -250,11 +288,13 @@
}
/**
+ * Loads the specified page data.
+ *
* @param pageMapName
* @param id
* @param versionNumber
* @param ajaxVersionNumber
- * @return
+ * @return page data or null if the page is no longer in
pagemap file
*/
public synchronized byte[] loadPage(String pageMapName, int id,
int versionNumber,
int ajaxVersionNumber)
@@ -274,7 +314,7 @@
}
/**
- *
+ * Deletes all files for this session.
*/
public synchronized void unbind()
{
@@ -285,6 +325,14 @@
}
}
+ /**
+ * Returns the folder for the specified sessions. If the folder doesn't
+ * exist and the create flag is set, the folder will be created.
+ *
+ * @param sessionId
+ * @param create
+ * @return
+ */
private File getSessionFolder(String sessionId, boolean create)
{
File storeFolder = new File(fileStoreFolder, appName +
"-filestore");
@@ -296,9 +344,15 @@
return sessionFolder;
}
- // for some reason, simple file.mkdirs sometimes fails under heavy load
+
+ /**
+ * Utility method for creating a directory
+ *
+ * @param file
+ */
private void mkdirs(File file)
{
+ // for some reason, simple file.mkdirs sometimes fails under
heavy load
for (int j = 0; j < 5; ++j)
{
for (int i = 0; i < 10; ++i)
@@ -319,6 +373,16 @@
log.error("Failed to make directory " + file);
}
+ /**
+ * Returns the file name for specified pagemap. If the session folder
+ * (folder that contains the file) does not exist and
createSessionFolder is
+ * true, the folder will becreated.
+ *
+ * @param sessionId
+ * @param pageMapName
+ * @param createSessionFolder
+ * @return file name for pagemap
+ */
private String getPageMapFileName(String sessionId, String pageMapName,
boolean createSessionFolder)
{
@@ -328,6 +392,11 @@
private final int maxSizePerPageMap;
+ /**
+ * Return maximum pagemap file size (in bytes).
+ *
+ * @return
+ */
protected int getMaxSizePerPageMap()
{
return maxSizePerPageMap;
@@ -335,6 +404,13 @@
private final int maxSizePerSession;
+ /**
+ * Returns maximum size per session (in bytes). After the session
exceeds
+ * this size, appropriate number of last recently used pagemap files
will be
+ * removed.
+ *
+ * @return
+ */
protected int getMaxSizePerSession()
{
return maxSizePerSession;
@@ -344,6 +420,11 @@
private final File fileStoreFolder;
+ /**
+ * Returns the "root" file store folder.
+ *
+ * @return
+ */
protected File getFileStoreFolder()
{
return fileStoreFolder;
@@ -352,12 +433,18 @@
private final String appName;
/**
- * Construct.
+ * Creates a new [EMAIL PROTECTED] DiskPageStore} instance.
*
* @param fileStoreFolder
+ * folder in which the session folders containing pagemap
files
+ * will be stored
* @param maxSizePerPagemap
+ * the maximum size of pagemap file (in bytes)
* @param maxSizePerSession
+ * the maximum size of session (in bytes)
* @param fileChannelPoolCapacity
+ * the maximum number of concurrently opened files (higher
number
+ * improves performance under heavy load).
*/
public DiskPageStore(File fileStoreFolder, int maxSizePerPagemap, int
maxSizePerSession,
int fileChannelPoolCapacity)
@@ -367,6 +454,12 @@
this.fileChannelPool = new
FileChannelPool(fileChannelPoolCapacity);
this.fileStoreFolder = fileStoreFolder;
+ if (maxSizePerSession < maxSizePerPageMap)
+ {
+ throw new IllegalArgumentException(
+ "Provided maximum session size must be
bigger than maximum pagemap size");
+ }
+
this.fileStoreFolder.mkdirs();
appName = Application.get().getApplicationKey();
@@ -380,11 +473,16 @@
}
/**
- * Construct.
+ * Creates a new [EMAIL PROTECTED] DiskPageStore} instance.
*
* @param maxSizePerPagemap
+ * the maximum size of pagemap file (in bytes)
* @param maxSizePerSession
+ * the maximum size of session (in bytes)
* @param fileChannelPoolCapacity
+ * the maximum number of concurrently opened files (higher
number
+ * improves performance under heavy load).
+ *
*/
public DiskPageStore(int maxSizePerPagemap, int maxSizePerSession, int
fileChannelPoolCapacity)
{
@@ -393,13 +491,16 @@
}
/**
- * Construct.
+ * Creates a new [EMAIL PROTECTED] DiskPageStore} instance.
*/
public DiskPageStore()
{
this((int)Bytes.megabytes(10).bytes(),
(int)Bytes.megabytes(100).bytes(), 50);
}
+ /**
+ * @see
org.apache.wicket.protocol.http.SecondLevelCacheSessionStore.IPageStore#destroy()
+ */
public void destroy()
{
fileChannelPool.destroy();
@@ -411,6 +512,15 @@
private Map /* <String, SessionEntry> */sessionIdToEntryMap = new
ConcurrentHashMap();
+ /**
+ * Returns the SessionEntry for session with given id. If the entry
does not
+ * yet exist and the createIfDoesNotExist attribute is set, new
SessionEntry
+ * will be created.
+ *
+ * @param sessionId
+ * @param createIfDoesNotExist
+ * @return
+ */
protected SessionEntry getSessionEntry(String sessionId, boolean
createIfDoesNotExist)
{
SessionEntry entry =
(SessionEntry)sessionIdToEntryMap.get(sessionId);
@@ -430,6 +540,10 @@
return entry;
}
+ /**
+ * @see
org.apache.wicket.protocol.http.SecondLevelCacheSessionStore.IPageStore#getPage(java.lang.String,
+ * java.lang.String, int, int, int)
+ */
public Page getPage(String sessionId, String pagemap, int id, int
versionNumber,
int ajaxVersionNumber)
{
@@ -444,6 +558,8 @@
}
else
{
+ // we need to make sure that the there are no
pending pages to
+ // be saved before loading a page
List pages = getPagesToSaveList(sessionId);
synchronized (pages)
{
@@ -461,10 +577,22 @@
return null;
}
+ /**
+ * @see
org.apache.wicket.protocol.http.SecondLevelCacheSessionStore.IPageStore#pageAccessed(java.lang.String,
+ * org.apache.wicket.Page)
+ */
public void pageAccessed(String sessionId, Page page)
{
}
+ /**
+ * Removes the page (or entire pagemap) from specified session.
+ *
+ * @param entry
+ * @param pageMap
+ * @param id
+ * page id to remove or -1 if the whole pagemap should be
removed
+ */
private void removePage(SessionEntry entry, String pageMap, int id)
{
if (id != -1)
@@ -477,6 +605,10 @@
}
}
+ /**
+ * @see
org.apache.wicket.protocol.http.SecondLevelCacheSessionStore.IPageStore#removePage(java.lang.String,
+ * java.lang.String, int)
+ */
public void removePage(String sessionId, String pageMap, int id)
{
SessionEntry entry = getSessionEntry(sessionId, false);
@@ -488,6 +620,8 @@
}
else
{
+ // we need to make sure that the there are no
pending pages to
+ // be saved before removing the page (or
pagemap)
List pages = getPagesToSaveList(sessionId);
synchronized (pages)
{
@@ -498,6 +632,13 @@
}
}
+ /**
+ * Stores the serialized pages. The storing is done either immediately
(in
+ * synchronous mode) or it's scheduled to be stored by the worker
thread.
+ *
+ * @param sessionId
+ * @param pages
+ */
protected void storeSerializedPages(String sessionId, List /*
<SerializedPage> */pages)
{
SessionEntry entry = getSessionEntry(sessionId, true);
@@ -527,6 +668,10 @@
}
+ /**
+ * @see
org.apache.wicket.protocol.http.SecondLevelCacheSessionStore.IPageStore#storePage(java.lang.String,
+ * org.apache.wicket.Page)
+ */
public void storePage(String sessionId, Page page)
{
List pages = serializePage(page);
@@ -536,6 +681,9 @@
storeSerializedPages(sessionId, pages);
}
+ /**
+ * @see
org.apache.wicket.protocol.http.SecondLevelCacheSessionStore.IPageStore#unbind(java.lang.String)
+ */
public void unbind(String sessionId)
{
SessionEntry entry =
(SessionEntry)sessionIdToEntryMap.get(sessionId);
@@ -565,6 +713,13 @@
// contains list of serialized pages to be saved - only non empty lists
private Map /* <String, List<SerializedPage>> */pagesToSaveActive = new
ConcurrentHashMap();
+ /**
+ * Returns the list of pages to be saved for the specified session id.
If
+ * the list is not found, new list is created.
+ *
+ * @param sessionId
+ * @return
+ */
protected List getPagesToSaveList(String sessionId)
{
List list = (List)pagesToSaveAll.get(sessionId);
@@ -583,7 +738,13 @@
return list;
}
- protected void flushPagesToSaveList(String sessionId, List list)
+ /**
+ * Saves all entries from the specified list.
+ *
+ * @param sessionId
+ * @param list
+ */
+ protected void flushPagesToSaveList(String sessionId, List /*
<SerializedPage> */list)
{
if (list != null)
{
@@ -596,7 +757,13 @@
}
}
- private void schedulePagesSave(String sessionId, List/* <SerializedPage
*/pages)
+ /**
+ * Schedules the pages to be saved by the worker thread.
+ *
+ * @param sessionId
+ * @param pages
+ */
+ private void schedulePagesSave(String sessionId, List/*
<SerializedPage> */pages)
{
List list = getPagesToSaveList(sessionId);
synchronized (list)
@@ -610,6 +777,12 @@
}
}
+ /**
+ * Worker thread that saves the serialized pages. Saving pages in the
+ * separate thread results in smoother performance under load.
+ *
+ * @author Matej Knopp
+ */
private class PageSavingThread implements Runnable
{
private volatile boolean stop = false;
@@ -618,6 +791,7 @@
{
while (stop == false)
{
+ // wait until we have something to save
while (pagesToSaveActive.isEmpty())
{
try
@@ -629,6 +803,7 @@
}
}
+ // iterate through lists of pages to be saved
for (Iterator i =
pagesToSaveActive.entrySet().iterator(); i.hasNext();)
{
Map.Entry entry = (Map.Entry)i.next();
@@ -655,7 +830,7 @@
}
/**
- *
+ * Stops the worker thread.
*/
public void stop()
{
@@ -663,6 +838,9 @@
}
};
+ /**
+ * Initializes the worker thread.
+ */
private void initPageSavingThread()
{
if (isSynchronous() == false)
@@ -677,11 +855,24 @@
private PageSavingThread pageSavingThread = null;
+ /**
+ * Returns the amount time in milliseconds for the saving thread to
sleep between
+ * checking whether there are pending serialized pages to be saved.
+ *
+ * @return
+ */
protected int getSavingThreadSleepTime()
{
return 100;
}
+ /**
+ * Returns whether the [EMAIL PROTECTED] DiskPageStore} should work in
synchronous or
+ * asynchronous mode. Asynchronous mode uses a worker thread to save
pages,
+ * which results in smoother performance.
+ *
+ * @return
+ */
protected boolean isSynchronous()
{
return false;
Modified:
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/FileChannelPool.java
URL:
http://svn.apache.org/viewvc/incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/FileChannelPool.java?view=diff&rev=555654&r1=555653&r2=555654
==============================================================================
---
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/FileChannelPool.java
(original)
+++
incubator/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/protocol/http/pagestore/FileChannelPool.java
Thu Jul 12 08:14:59 2007
@@ -267,9 +267,9 @@
}
/**
- * Closes the file channel with given name and removes it from pool. If
the
- * channel is in use, the pool first waits until the chanel is returned
to
- * the pool and then closes it.
+ * Closes the file channel with given name and removes it from pool.
Also
+ * removes the file from file system. If the channel is in use, the pool
+ * first waits until the chanel is returned to the pool and then closes
it.
*
* @param name
*/
