org.apache.felix.framework.cache

Interface Content

All Known Implementing Classes:

ContentDirectoryContent, DirectoryContent, ExtensionManager, JarContent

public interface Content

Method Summary

Modifier and Type	Method and Description
void	close() This method must be called when the content is no longer needed so that any resourses being used (e.g., open files) can be closed.
java.util.Enumeration<java.lang.String>	getEntries() Returns an enumeration of entry names as String objects.
byte[]	getEntryAsBytes(java.lang.String name) This method returns the named entry as an array of bytes.
Content	getEntryAsContent(java.lang.String name) This method returns the named entry as an IContent Typically, this method only makes sense for entries that correspond to some form of aggregated resource (e.g., an embedded JAR file or directory), but implementations are free to interpret this however makes sense.
java.lang.String	getEntryAsNativeLibrary(java.lang.String name) This method returns the named entry as a file in the file system for use as a native library.
java.io.InputStream	getEntryAsStream(java.lang.String name) This method returns the named entry as an input stream.
java.net.URL	getEntryAsURL(java.lang.String name) This method allows retrieving an entry as a local URL.
boolean	hasEntry(java.lang.String name) This method determines if the specified named entry is contained in the associated content.

Method Detail

close

void close()

This method must be called when the content is no longer needed so that any resourses being used (e.g., open files) can be closed. Once this method is called, the content is no longer usable. If the content is already closed, then calls on this method should have no effect.

hasEntry

boolean hasEntry(java.lang.String name)

This method determines if the specified named entry is contained in the associated content. The entry name is a relative path with '/' separators.

Parameters:

name - The name of the entry to find.

Returns:

true if a corresponding entry was found, false otherwise.

getEntries

java.util.Enumeration<java.lang.String> getEntries()

Returns an enumeration of entry names as String objects. An entry name is a path constructed with '/' as path element separators and is relative to the root of the content. Entry names for entries that represent directories should end with the '/' character.

getEntryAsBytes

byte[] getEntryAsBytes(java.lang.String name)

This method returns the named entry as an array of bytes.

Parameters:

name - The name of the entry to retrieve as a byte array.

Returns:

An array of bytes if the corresponding entry was found, null otherwise.

getEntryAsStream

java.io.InputStream getEntryAsStream(java.lang.String name)
                              throws java.io.IOException

This method returns the named entry as an input stream.

Parameters:

name - The name of the entry to retrieve as an input stream.

Returns:

An input stream if the corresponding entry was found, null otherwise.

Throws:

java.io.IOException - if any error occurs.

java.io.IOException

getEntryAsContent

Content getEntryAsContent(java.lang.String name)

This method returns the named entry as an IContent Typically, this method only makes sense for entries that correspond to some form of aggregated resource (e.g., an embedded JAR file or directory), but implementations are free to interpret this however makes sense. This method should return a new IContent instance for every invocation and the caller is responsible for opening and closing the returned content object.

Parameters:

name - The name of the entry to retrieve as an IContent.

Returns:

An IContent instance if a corresponding entry was found, null otherwise.

getEntryAsNativeLibrary

java.lang.String getEntryAsNativeLibrary(java.lang.String name)

This method returns the named entry as a file in the file system for use as a native library. It may not be possible for all content implementations (e.g., memory only) to implement this method, in which case it is acceptable to return null. Since native libraries can only be associated with a single class loader, this method should return a unique file per request.

Parameters:

name - The name of the entry to retrieve as a file.

Returns:

A string corresponding to the absolute path of the file if a corresponding entry was found, null otherwise.

getEntryAsURL

java.net.URL getEntryAsURL(java.lang.String name)

This method allows retrieving an entry as a local URL.

Parameters:

name - The name of the entry to retrieve as a URL

Returns:

A URL using a local protocol such as file, jar or null if not possible.