org.conqat.lib.commons.filesystem

Class PathBasedContentProviderBase

java.lang.Object

org.conqat.lib.commons.filesystem.PathBasedContentProviderBase

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public abstract class PathBasedContentProviderBase
extends java.lang.Object
implements java.io.Closeable

Base class for objects that provide access to the content of various elements using a path for access. This basically abstracts the differences between plain directories and ZIP files (containing multiple entries).

Constructor Summary

Constructors

Constructor and Description
PathBasedContentProviderBase()

Method Summary

Modifier and Type	Method and Description
abstract void	close()
static PathBasedContentProviderBase	createProvider(java.io.File file) Creates a suitable provider for a file.
abstract java.util.Collection<java.lang.String>	getPaths() Returns the relative paths to all available elements that carry content.
java.util.Collection<java.lang.String>	getPathsWithPrefix(java.lang.String prefix) Returns all paths starting with a given prefix.
abstract java.io.InputStream	openStream(java.lang.String relativePath) Opens a stream to the element identified by the given path.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PathBasedContentProviderBase

public PathBasedContentProviderBase()

Method Detail

getPaths

public abstract java.util.Collection<java.lang.String> getPaths()
                                                         throws java.io.IOException

Returns the relative paths to all available elements that carry content. These correspond to file names or names of ZIP file entries. The returned paths are guaranteed to use a forward slash as the path separator.

Throws:

java.io.IOException

close

public abstract void close()
                    throws java.io.IOException

This closes the content provider itself, i.e. after closing, no new streams may be opened. Whether existing streams are closed depends on the implementation, but it is recommended to close any streams returned from openStream(String) yourself and to not use any of these streams after calling this method.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Throws:

java.io.IOException

openStream

public abstract java.io.InputStream openStream(java.lang.String relativePath)
                                        throws java.io.IOException

Opens a stream to the element identified by the given path. This should be one of the paths returned by the getPaths() method. The returned stream must be closed by the caller.

Throws:

java.io.IOException

getPathsWithPrefix

public java.util.Collection<java.lang.String> getPathsWithPrefix(java.lang.String prefix)
                                                          throws java.io.IOException

Returns all paths starting with a given prefix.

Throws:

java.io.IOException

createProvider

public static PathBasedContentProviderBase createProvider(java.io.File file)
                                                   throws java.io.IOException

Creates a suitable provider for a file. This works for directories as well as ZIP/JAR files. The returned provider has to be closed at the end.

Throws:

java.io.IOException - if accessing the file fails or the file is not of suitable format (i.e. no directory or ZIP file).