/*
* JBoss, Home of Professional Open Source
* Copyright 2007, Red Hat Middleware LLC, and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.ejb3.cache.impl;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import org.jboss.ejb3.cache.Identifiable;
import org.jboss.ejb3.cache.ObjectStore;
import org.jboss.logging.Logger;
import org.jboss.serial.io.JBossObjectInputStream;
import org.jboss.serial.io.JBossObjectOutputStream;
/**
* Stores objects in a directory via serialization.
*
* @author <a href="mailto:carlo.dewolf@jboss.com">Carlo de Wolf</a>
* @version $Revision: 65339 $
*/
public class FileObjectStore<T extends Identifiable> implements ObjectStore<T>
{
private static final Logger log = Logger.getLogger(FileObjectStore.class);
private File storageDirectory;
private static class DeleteFileAction implements PrivilegedAction<Boolean>
{
File file;
DeleteFileAction(File file)
{
this.file = file;
}
public Boolean run()
{
return file.delete();
}
static boolean delete(File file)
{
DeleteFileAction action = new DeleteFileAction(file);
return AccessController.doPrivileged(action);
}
}
private static class FISAction implements PrivilegedExceptionAction<FileInputStream>
{
File file;
FISAction(File file)
{
this.file = file;
}
public FileInputStream run() throws FileNotFoundException
{
FileInputStream fis = new FileInputStream(file);
return fis;
}
static FileInputStream open(File file) throws FileNotFoundException
{
FISAction action = new FISAction(file);
FileInputStream fis = null;
try
{
fis = AccessController.doPrivileged(action);
}
catch (PrivilegedActionException e)
{
throw (FileNotFoundException) e.getException();
}
return fis;
}
}
private static class FOSAction implements PrivilegedExceptionAction<FileOutputStream>
{
File file;
FOSAction(File file)
{
this.file = file;
}
public FileOutputStream run() throws FileNotFoundException
{
FileOutputStream fis = new FileOutputStream(file);
return fis;
}
static FileOutputStream open(File file) throws FileNotFoundException
{
FOSAction action = new FOSAction(file);
FileOutputStream fos = null;
try
{
fos = AccessController.doPrivileged(action);
}
catch (PrivilegedActionException e)
{
throw (FileNotFoundException) e.getException();
}
return fos;
}
}
private static class MkdirsFileAction implements PrivilegedAction<Boolean>
{
File file;
MkdirsFileAction(File file)
{
this.file = file;
}
public Boolean run()
{
return file.mkdirs();
}
static boolean mkdirs(File file)
{
MkdirsFileAction action = new MkdirsFileAction(file);
return AccessController.doPrivileged(action);
}
}
protected File getFile(Object key)
{
return new File(storageDirectory, String.valueOf(key) + ".ser");
}
@SuppressWarnings("unchecked")
public T load(Object key)
{
File file = getFile(key);
if(!file.exists())
return null;
log.debug("loading state from " + file);
try
{
FileInputStream fis = FISAction.open(file);
ObjectInputStream in = new JBossObjectInputStream(fis);
try
{
return (T) in.readObject();
}
finally
{
in.close();
DeleteFileAction.delete(file);
}
}
catch(ClassNotFoundException e)
{
throw new RuntimeException("failed to load object " + key, e);
}
catch(IOException e)
{
throw new RuntimeException("failed to load object " + key, e);
}
}
public void setStorageDirectory(String dirName)
{
storageDirectory = new File(dirName);
}
public void start()
{
assert storageDirectory != null : "storageDirectory is null";
if(!storageDirectory.exists())
{
if(!MkdirsFileAction.mkdirs(storageDirectory))
throw new RuntimeException("Unable to create storage directory " + storageDirectory);
storageDirectory.deleteOnExit();
}
if(!storageDirectory.isDirectory())
throw new RuntimeException("Storage directory " + storageDirectory + " is not a directory");
}
public void stop()
{
// TODO: implement
}
public void store(T obj)
{
File file = getFile(obj.getId());
file.deleteOnExit();
log.debug("saving state to " + file);
try
{
FileOutputStream fos = FOSAction.open(file);
ObjectOutputStream out = new JBossObjectOutputStream(fos);
try
{
out.writeObject(obj);
out.flush();
}
finally
{
out.close();
}
}
catch(IOException e)
{
throw new RuntimeException("failed to store object " + obj.getId(), e);
}
}
}