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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.vfs2;
import java.io.File;
import java.lang.reflect.Constructor;
import java.net.URI;
import java.net.URL;
import java.net.URLStreamHandlerFactory;
import java.util.Collection;
import org.apache.commons.logging.Log;
import org.apache.commons.vfs2.operations.FileOperationProvider;
/**
* A FileSystemManager manages a set of file systems. This interface is used to locate a {@link FileObject} by name from
* one of those file systems.
*
* To locate a {@link FileObject}, use one of the {@code resolveFile()} methods.
*
*
File Naming
*
* A file system manager can recognise several types of file names:
*
* - Absolute URI. These must start with a scheme, such as {@code file:} or {@code ftp:}, followed by a scheme
* dependent file name. Some examples: {@code file:/c:/somefile} or {@code ftp://somewhere.org/somefile}.
* - Absolute local file name. For example, {@code /home/someuser/a-file} or {@code c:\dir\somefile.html}. Elements in
* the name can be separated using any of the following characters: {@code /}, {@code \}, or the native file separator
* character. For example, the following file names are the same: {@code c:\somedir\somefile.xml} and
* {@code c:/somedir/somefile.xml}.
* - Relative path. For example: {@code ../somefile} or {@code somedir/file.txt}. The file system manager resolves
* relative paths against its base file. Elements in the relative path can be separated using {@code /},
* {@code \}, or file system specific separator characters. Relative paths may also contain {@code ..} and {@code .}
* elements. See {@link FileObject#resolveFile} for more details.
*
*/
public interface FileSystemManager {
/**
* Returns the base file used to resolve relative paths.
*
* @return The base FileObject.
* @throws FileSystemException if an error occurs.
*/
FileObject getBaseFile() throws FileSystemException;
/**
* Locates a file by name. Equivalent to calling {@code resolveFile(getBaseFile(), name)}.
*
* @param name The name of the file.
* @return The file. Never returns null.
* @throws FileSystemException On error parsing the file name.
*/
FileObject resolveFile(String name) throws FileSystemException;
/**
* Locates a file by name. Equivalent to calling {@code resolveFile(getBaseFile(), name)}.
*
* @param name The name of the file.
* @param fileSystemOptions The FileSystemOptions used for FileSystem creation. All files that are later resolved
* relative to the returned {@code FileObject} share the options.
* @return The file. Never returns null.
* @throws FileSystemException On error parsing the file name.
*/
FileObject resolveFile(String name, FileSystemOptions fileSystemOptions) throws FileSystemException;
/**
* Locates a file by name. The name is resolved as described above. That is, the name can be
* either an absolute URI, an absolute file name, or a relative path to be resolved against {@code baseFile}.
*
* Note that the file does not have to exist when this method is called.
*
* @param baseFile The base file to use to resolve relative paths. May be null if the name is an absolute file name.
* @param name The name of the file.
* @return The file. Never returns null.
* @throws FileSystemException On error parsing the file name.
*/
FileObject resolveFile(FileObject baseFile, String name) throws FileSystemException;
/**
* Locates a file by name. See {@link #resolveFile(FileObject, String)} for details.
*
* @param baseFile The base file to use to resolve relative paths. Must not be {@code null}, not even if the
* name is absolute.
* @param name The name of the file.
* @return The file. Never returns null.
* @throws FileSystemException On error parsing the file name.
*/
FileObject resolveFile(File baseFile, String name) throws FileSystemException;
/**
* Resolves a name, relative to this file name. Equivalent to calling
* {@code resolveName( path, NameScope.FILE_SYSTEM )}.
*
* @param root the base filename
* @param name The name to resolve.
* @return A {@link FileName} object representing the resolved file name.
* @throws FileSystemException If the name is invalid.
*/
FileName resolveName(FileName root, String name) throws FileSystemException;
/**
* Resolves a name, relative to the "root" file name. Refer to {@link NameScope} for a description of how names are
* resolved.
*
* @param root the base filename
* @param name The name to resolve.
* @param scope The {@link NameScope} to use when resolving the name.
* @return A {@link FileName} object representing the resolved file name.
* @throws FileSystemException If the name is invalid.
*/
FileName resolveName(FileName root, String name, NameScope scope) throws FileSystemException;
/**
* Converts a local file into a {@link FileObject}.
*
* @param file The file to convert.
* @return The {@link FileObject} that represents the local file. Never returns null.
* @throws FileSystemException On error converting the file.
*/
FileObject toFileObject(File file) throws FileSystemException;
/**
* Creates a layered file system. A layered file system is a file system that is created from the contents of a
* file, such as a zip or tar file.
*
* @param provider The name of the file system provider to use. This name is the same as the scheme used in URI to
* identify the provider.
* @param file The file to use to create the file system.
* @return The root file of the new file system.
* @throws FileSystemException On error creating the file system.
*/
FileObject createFileSystem(String provider, FileObject file) throws FileSystemException;
/**
* Closes the given filesystem.
*
* If you use VFS as singleton it is VERY dangerous to call this method.
*
* @param filesystem The FileSystem to close.
*/
void closeFileSystem(FileSystem filesystem);
/**
* Creates a layered file system. A layered file system is a file system that is created from the contents of a
* file, such as a zip or tar file.
*
* @param file The file to use to create the file system.
* @return The root file of the new file system.
* @throws FileSystemException On error creating the file system.
*/
FileObject createFileSystem(FileObject file) throws FileSystemException;
/**
* Creates an empty virtual file system. Can be populated by adding junctions to it.
*
* @param rootUri The root URI to use for the new file system. Can be null.
* @return The root file of the new file system.
* @throws FileSystemException if an error occurs creating the VirtualFileSystem.
*/
FileObject createVirtualFileSystem(String rootUri) throws FileSystemException;
/**
* Creates a virtual file system. The file system will contain a junction at the fs root to the supplied root file.
*
* @param rootFile The root file to backs the file system.
* @return The root of the new file system.
* @throws FileSystemException if an error occurs creating the VirtualFileSystem.
*/
FileObject createVirtualFileSystem(FileObject rootFile) throws FileSystemException;
/**
* Returns a stream handler factory to enable URL lookup using this FileSystemManager.
*
* @return the URLStreamHandlerFactory.
*/
URLStreamHandlerFactory getURLStreamHandlerFactory();
/**
* Determines if a layered file system can be created for a given file.
*
* @param file The file to check for.
* @return true if the FileSystem can be created.
* @throws FileSystemException if an error occurs.
*/
boolean canCreateFileSystem(FileObject file) throws FileSystemException;
/**
* Get the cache used to cache file objects.
*
* @return The FilesCache.
*/
FilesCache getFilesCache();
/**
* Get the cache strategy used.
*
* @return the CacheStrategy.
*/
CacheStrategy getCacheStrategy();
/**
* Get the file object decorator used.
*
* @return the file object decorator Class.
*/
Class getFileObjectDecorator();
/**
* The constructor associated to the fileObjectDecorator. We cache it here for performance reasons.
*
* @return the Constructor associated with the FileObjectDecorator.
*/
Constructor getFileObjectDecoratorConst();
/**
* The class to use to determine the content-type (mime-type).
*
* @return the FileContentInfoFactory.
*/
FileContentInfoFactory getFileContentInfoFactory();
/**
* Returns true if this manager has a provider for a particular scheme.
*
* @param scheme The scheme for which a provider should be checked.
* @return true if a provider for the scheme is available.
*/
boolean hasProvider(String scheme);
/**
* Get the schemes currently available.
*
* @return An array of available scheme names that are supported.
*/
String[] getSchemes();
/**
* Get the capabilities for a given scheme.
*
* @param scheme The scheme to use to locate the provider's capabilities.
* @return A Collection of the various capabilities.
* @throws FileSystemException if the given scheme is not konwn.
*/
Collection getProviderCapabilities(String scheme) throws FileSystemException;
/**
* Sets the logger to use.
*
* @param log The logger to use.
*/
void setLogger(Log log);
/**
* Get the configuration builder for the given scheme.
*
* @param scheme The schem to use to obtain the FileSystemConfigBuidler.
* @return A FileSystemConfigBuilder appropriate for the given scheme.
* @throws FileSystemException if the given scheme is not konwn.
*/
FileSystemConfigBuilder getFileSystemConfigBuilder(String scheme) throws FileSystemException;
/**
* Resolve the uri to a filename.
*
* @param uri The uri to resolve.
* @return A FileName that matches the uri.
* @throws FileSystemException if this is not possible.
*/
FileName resolveURI(String uri) throws FileSystemException;
// -- OPERATIONS --
/**
* Adds the specified FileOperationProvider for the specified scheme.
*
* Several FileOperationProvider's might be registered for the same scheme. For example, for {@code "file"} scheme
* we can register {@code SvnWsOperationProvider} and {@code CvsOperationProvider.}
*
* @param scheme The scheme assoicated with this provider.
* @param operationProvider The FileOperationProvider to add.
* @throws FileSystemException if an error occurs.
*/
void addOperationProvider(String scheme, FileOperationProvider operationProvider) throws FileSystemException;
/**
* @see FileSystemManager#addOperationProvider(String, org.apache.commons.vfs2.operations.FileOperationProvider)
*
* @param schemes The schemes that will be associated with the provider.
* @param operationProvider The FileOperationProvider to add.
* @throws FileSystemException if an error occurs.
*/
void addOperationProvider(String[] schemes, FileOperationProvider operationProvider) throws FileSystemException;
/**
* Get Providers for file operations.
*
* @param scheme the scheme for wich we want to get the list af registered providers.
*
* @return the registered FileOperationProviders for the specified scheme. If there were no providers registered for
* the scheme, it returns null.
*
* @throws FileSystemException if an error occurs.
*/
FileOperationProvider[] getOperationProviders(String scheme) throws FileSystemException;
/**
* Resolves a URI into a {@link FileObject}.
*
* @param uri The URI to convert.
* @return The {@link FileObject} that represents the URI. Never returns null.
* @throws FileSystemException On error converting the file.
* @since 2.1
*/
FileObject resolveFile(URI uri) throws FileSystemException;
/**
* Resolves a URL into a {@link FileObject}.
*
* @param url The URL to convert.
* @return The {@link FileObject} that represents the URL. Never returns null.
* @throws FileSystemException On error converting the file.
* @since 2.1
*/
FileObject resolveFile(URL url) throws FileSystemException;
}