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package org.xmldb.api.reference;
/*
* The XML:DB Initiative Software License, Version 1.0
*
*
* Copyright (c) 2000-2003 The XML:DB Initiative. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* XML:DB Initiative (http://www.xmldb.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The name "XML:DB Initiative" must not be used to endorse or
* promote products derived from this software without prior written
* permission. For written permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "XML:DB",
* nor may "XML:DB" appear in their name, without prior written
* permission of the XML:DB Initiative.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the XML:DB Initiative. For more information
* on the XML:DB Initiative, please see Collection is implemented as a directory in the file system.
*/
public class CollectionImpl extends SimpleCollection {
protected File collection = null;
public CollectionImpl(String path) throws FileNotFoundException,
XMLDBException {
super();
collection = new File(path);
if ( ! collection.isDirectory() ) {
throw new FileNotFoundException();
}
registerService(new XPathQueryServiceImpl());
registerService(new CollectionManagementServiceImpl(path));
}
/**
* Returns the name of the collection
*
* @return the name of the object.
*/
public String getName() throws XMLDBException {
return collection.getName();
}
/**
* Returns the parent collection for this collection or null if no parent
* collection exists.
*
* @return the parent Collection instance.
*/
public Collection getParentCollection() throws XMLDBException {
if ( collection.getParent() == null ) {
return null;
}
try {
return (Collection) new CollectionImpl(collection.getParent());
}
catch (FileNotFoundException e) {
return null;
}
}
/**
* Returns the number of child collections under this
* Collection.
*
* @return the number of child collections.
*/
public int getChildCollectionCount() throws XMLDBException {
return collection.list(new DirectoryFilter()).length;
}
/**
* Returns a list of collection names naming all child collections
* of the current collection.
*
* @return an array containing collection names for all child
* collections.
*/
public String[] listChildCollections() throws XMLDBException {
return collection.list(new DirectoryFilter());
}
/**
* Returns a Collection instance for the requested child collection
* if it exists.
*
* @param name the name of the child collection to retrieve.
* @return the requested child collection or null if it couldn't be found.
*/
public Collection getChildCollection(String name) throws XMLDBException {
try {
return (Collection) new CollectionImpl(collection.getPath() +
File.separator + name);
}
catch (FileNotFoundException e) {
return null;
}
}
/**
* Returns the number of resources currently stored in this collection or 0
* if the collection is empty.
*
* @return the number of resources in the collection.
*/
public int getResourceCount() throws XMLDBException {
return collection.list(new FileFilter()).length;
}
/**
* Returns a list of the ids for all resources stored in the collection.
*
* @return a string array containing the names for all
* Resources in the collection.
*/
public String[] listResources() throws XMLDBException {
return collection.list(new FileFilter());
}
/**
* Creates a new empty Resource with the provided id.
*
* @param id the unique id to associate with the created Resource.
* @param type the Resource type to create.
* @return an empty Resource instance.
*/
public Resource createResource(String id, String type) throws XMLDBException {
if ( ( id == null ) || ( id.equals("") ) ) {
id = createId();
}
if ( type.equals(XMLResource.RESOURCE_TYPE) ) {
return new XMLResourceImpl(this, id, id);
}
else if ( type.equals(BinaryResource.RESOURCE_TYPE) ) {
return new BinaryResourceImpl(this, id);
}
else {
throw new XMLDBException(ErrorCodes.UNKNOWN_RESOURCE_TYPE);
}
}
/**
* Removes the Resource from the database.
*
* @param res the resource to remove.
*/
public void removeResource(Resource res) throws XMLDBException {
if ( (res.getId() == null) || (res.getId().equals("")) ) {
throw new XMLDBException(ErrorCodes.INVALID_RESOURCE);
}
File target = new File(collection, res.getId());
if ( (target == null) || (target.isDirectory()) ) {
throw new XMLDBException(ErrorCodes.NO_SUCH_RESOURCE);
}
target.delete();
}
/**
* Stores the provided resource into the database.
*
* @param res the resource to store in the database.
*/
public void storeResource(Resource res) throws XMLDBException {
try {
validateResource(res);
File target = new File(collection, res.getId());
FileOutputStream file = new FileOutputStream(target);
if ( res.getResourceType().equals(XMLResource.RESOURCE_TYPE) ) {
file.write(((String) res.getContent()).getBytes());
}
else if ( res.getResourceType().equals(BinaryResource.RESOURCE_TYPE) ) {
file.write((byte[]) res.getContent());
}
else {
throw new XMLDBException(ErrorCodes.INVALID_RESOURCE);
}
file.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
/**
* Retrieves a Resource from the database.
*
* @param id the unique id for the requested resource.
* @return The retrieved Resource instance.
*/
public Resource getResource(String id) throws XMLDBException {
try {
File target = new File(collection, id);
if ( target.isFile() ) {
FileInputStream file = new FileInputStream(target);
byte[] contents = new byte[file.available()];
file.read(contents);
file.close();
// If the file starts with < we'll assume XML. All test data has
// the XML header. TODO: add a better test
if ( contents[0] == '<' ) {
return new XMLResourceImpl(this, id, id, new String(contents));
}
else {
return new BinaryResourceImpl(this, id, contents);
}
}
}
catch (IOException e) {
e.printStackTrace();
}
return null;
}
/**
* Creates a new unique ID within the context of the Collection
*
* @return the created id as a string.
*/
public String createId() throws XMLDBException {
// This isn't robust but for this impl it is good enough
return collection.getName() + System.currentTimeMillis() +
new Random().nextLong();
}
/**
* Releases all resources consumed by the Collection.
*/
public void close() throws XMLDBException {
// nothing to do here.
}
/**
* Makes sure the resource is valid.
*/
protected void validateResource(Resource res) throws XMLDBException {
if ( (res.getId() == null) || (res.getId().equals("")) ||
(res.getContent() == null) ) {
throw new XMLDBException(ErrorCodes.INVALID_RESOURCE);
}
}
}
/**
* Only accept directories
*/
class DirectoryFilter implements FilenameFilter {
public boolean accept(File dir, String name) {
if ( new File(dir, name).isDirectory() ) {
return true;
}
return false;
}
}
/**
* Only accept files
*/
class FileFilter implements FilenameFilter {
public boolean accept(File dir, String name) {
if ( new File(dir, name).isFile() ) {
return true;
}
return false;
}
}