/*
* JBoss, Home of Professional Open Source
* Copyright 2006, JBoss Inc., 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.virtual.plugins.context;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.io.ObjectInputStream.GetField;
import java.io.ObjectOutputStream.PutField;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
import org.jboss.logging.Logger;
import org.jboss.virtual.VFSUtils;
import org.jboss.virtual.VirtualFile;
import org.jboss.virtual.plugins.vfs.helpers.PathTokenizer;
import org.jboss.virtual.spi.VFSContext;
import org.jboss.virtual.spi.VFSContextFactory;
import org.jboss.virtual.spi.VFSContextFactoryLocator;
import org.jboss.virtual.spi.VirtualFileHandler;
/**
* AbstractVirtualFileHandler.
*
* @author <a href="adrian@jboss.com">Adrian Brock</a>
* @author Scott.Stark@jboss.org
* @version $Revision: 1.1 $
*/
public abstract class AbstractVirtualFileHandler implements VirtualFileHandler
{
/** The log */
protected Logger log = Logger.getLogger(getClass());
/** serialVersionUID */
private static final long serialVersionUID = 1L;
/** The class serial fields */
private static final ObjectStreamField[] serialPersistentFields = {
new ObjectStreamField("rootURI", URI.class),
new ObjectStreamField("parent", VirtualFileHandler.class),
new ObjectStreamField("name", String.class),
new ObjectStreamField("vfsUrl", URL.class)
};
/** The VFS context
* @serialField rootURI URI the VFS context rootURI
*/
private VFSContext context;
/** The parent
* @serialField parent VirtualFileHandler the virtual file parent
*/
private VirtualFileHandler parent;
/** The name
* @serialField name String the virtual file name
*/
private String name;
/** The vfsPath */
private transient String vfsPath;
protected URL vfsUrl;
/** The reference count */
private transient AtomicInteger references = new AtomicInteger(0);
protected transient long cachedLastModified;
/**
* Create a new handler
*
* @param context the context
* @param parent the parent
* @param name the name
* @throws IllegalArgumentException if the context or name is null;
*/
protected AbstractVirtualFileHandler(VFSContext context, VirtualFileHandler parent, String name)
{
if (context == null)
throw new IllegalArgumentException("Null context");
if (name == null)
throw new IllegalArgumentException("Null name");
this.context = context;
this.parent = parent;
this.name = VFSUtils.fixName(name);
}
public boolean hasBeenModified() throws IOException
{
long last = getLastModified();
if (cachedLastModified != last)
{
cachedLastModified = last;
return true;
}
return false;
}
public String getName()
{
return name;
}
public String getPathName()
{
if (vfsPath == null)
{
StringBuilder pathName = new StringBuilder();
initPath(pathName);
vfsPath = pathName.toString();
}
return vfsPath;
}
public URL toURL() throws MalformedURLException, URISyntaxException
{
return toURI().toURL();
}
public URL toVfsUrl() throws MalformedURLException, URISyntaxException
{
return vfsUrl;
}
/**
* Initialise the path into the path name
*
* @param pathName the path name
* @return whether it added anything
*/
private boolean initPath(StringBuilder pathName)
{
if (parent != null)
{
if (parent instanceof AbstractVirtualFileHandler)
{
AbstractVirtualFileHandler handler = (AbstractVirtualFileHandler) parent;
if (handler.initPath(pathName))
pathName.append('/');
}
else
{
pathName.append(parent.getPathName());
}
pathName.append(getName());
return true;
}
return false;
}
public VirtualFile getVirtualFile()
{
checkClosed();
increment();
return new VirtualFile(this);
}
public VirtualFileHandler getParent() throws IOException
{
checkClosed();
return parent;
}
public VFSContext getVFSContext()
{
checkClosed();
return context;
}
/**
* Increment the reference count
*
* @return the resulting count
*/
private int increment()
{
return references.incrementAndGet();
}
/**
* Decrement the reference count
*
* @return the resulting count
*/
private int decrement()
{
return references.decrementAndGet();
}
/**
* Check whether we are closed
*
* @throws IllegalStateException when closed
*/
protected void checkClosed() throws IllegalStateException
{
if (references.get() < 0)
throw new IllegalStateException("Closed " + this);
}
public void close()
{
if (decrement() == 0)
doClose();
}
/**
* The real close
*/
protected void doClose()
{
// nothing
}
/**
* Structured implementation of find child
*
* @param path the path
* @return the handler
* @throws IOException for any error accessing the virtual file system
* @throws IllegalArgumentException for a null name
*/
public VirtualFileHandler structuredFindChild(String path) throws IOException
{
checkClosed();
// Parse the path
String[] tokens = PathTokenizer.getTokens(path);
if (tokens == null || tokens.length == 0)
return this;
// Go through each context starting from ours
// check the parents are not leaves.
VirtualFileHandler current = this;
for (int i = 0; i < tokens.length; ++i)
{
if (current.isLeaf())
throw new IOException("File cannot have children: " + current);
if (current instanceof StructuredVirtualFileHandler)
{
StructuredVirtualFileHandler structured = (StructuredVirtualFileHandler) current;
current = structured.createChildHandler(tokens[i]);
}
else
{
String remainingPath = PathTokenizer.getRemainingPath(tokens, i);
return current.findChild(remainingPath);
}
}
// The last one is the result
return current;
}
/**
* Simple implementation of findChild
*
* @param path the path
* @return the handler
* @throws IOException for any error accessing the virtual file system
* @throws IllegalArgumentException for a null name
*/
public VirtualFileHandler simpleFindChild(String path) throws IOException
{
if (path == null)
throw new IllegalArgumentException("Null path");
if (path.length() == 0)
return this;
List<VirtualFileHandler> children = getChildren(false);
for (VirtualFileHandler child : children)
{
if (child.getName().equals(path))
return child;
}
throw new IOException("Child not found " + path + " for " + this);
}
@Override
public String toString()
{
StringBuilder buffer = new StringBuilder();
buffer.append(getClass().getSimpleName());
buffer.append('@');
buffer.append(System.identityHashCode(this));
buffer.append("[path=").append(getPathName());
buffer.append(" context=").append(context.getRootURI());
buffer.append(" real=").append(safeToURLString());
buffer.append(']');
return buffer.toString();
}
@Override
public int hashCode()
{
return getPathName().hashCode();
}
@Override
public boolean equals(Object obj)
{
if (this == obj)
return true;
if (obj == null || obj instanceof VirtualFileHandler == false)
return false;
VirtualFileHandler other = (VirtualFileHandler) obj;
if (getVFSContext().equals(other.getVFSContext()) == false)
return false;
if (getPathName().equals(other.getPathName()) == false)
return false;
return true;
}
@Override
protected void finalize() throws Throwable
{
close();
}
/**
* Safely get a url version of the string
*
* @return the string or unknown if there is an error
*/
private String safeToURLString()
{
try
{
return toURI().toString();
}
catch (URISyntaxException ignored)
{
return "<unknown>";
}
}
private void writeObject(ObjectOutputStream out)
throws IOException
{
PutField fields = out.putFields();
fields.put("rootURI", this.getVFSContext().getRootURI());
fields.put("parent", parent);
fields.put("name", name);
fields.put("vfsUrl", vfsUrl);
out.writeFields();
}
private void readObject(ObjectInputStream in)
throws IOException, ClassNotFoundException
{
// Read in the serialPersistentFields
GetField fields = in.readFields();
URI rootURI = (URI) fields.get("rootURI", null);
this.parent = (VirtualFileHandler) fields.get("parent", null);
this.name = (String) fields.get("name", null);
VFSContextFactory factory = VFSContextFactoryLocator.getFactory(rootURI);
this.context = factory.getVFS(rootURI);
this.references = new AtomicInteger(0);
this.vfsUrl = (URL)fields.get("vfsUrl", null);
// Restore the log
log = Logger.getLogger(getClass());
}
}