com.allanbank.mongodb.gridfs

Class GridFs

java.lang.Object

com.allanbank.mongodb.gridfs.GridFs

public class GridFs
extends Object

GridFs provides an interface for working with a GridFS collection.

This implementation uses a ObjectId as the id when writing and stores the name of the file in the files collection document's "filename" field. To unlink(String) or read(String, OutputStream) a file from the collection the _id field may contain any value but the filename field must be present.

API Notice:

This class is part of the driver's API. Public and protected members will be deprecated for at least 1 non-bugfix release (version numbers are <major>.<minor>.<bugfix>) before being removed or modified.

Copyright ©:

2012, Allanbank Consulting, Inc., All Rights Reserved

Field Summary

Fields

Modifier and Type	Field and Description
static String	CHUNKS_SUFFIX The suffix for the chunks collection.
static int	DEFAULT_CHUNK_SIZE The default chunk size.
static String	DEFAULT_ROOT The suffix for the files collection.
static String	FILES_SUFFIX The suffix for the files collection.

Constructor Summary

Constructors

Constructor and Description
GridFs(MongoDatabase database) Creates a new GridFs.
GridFs(MongoDatabase database, String rootName) Creates a new GridFs.
GridFs(String mongoDbUri) Creates a new GridFs.
GridFs(String mongoDbUri, String rootName) Creates a new GridFs.

Method Summary

Methods

Modifier and Type	Method and Description
int	getChunkSize() Returns the size for a chunk written.
void	read(String name, OutputStream sink) Reads a file from the GridFS collections and writes the contents to the sink
void	setChunkSize(int chunkSize) Sets the value of size for a chunk written.
boolean	unlink(String name) Unlinks (deletes) the file from the GridFS collections.
void	write(String name, InputStream source) Attempts to write a file into the GridFS collections using the specified name for the file and deriving the chunks from the data read from the source.

Methods inherited from class java.lang.Object

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

Field Detail

CHUNKS_SUFFIX

public static final String CHUNKS_SUFFIX

The suffix for the chunks collection.

See Also:

Constant Field Values

DEFAULT_CHUNK_SIZE

public static final int DEFAULT_CHUNK_SIZE

The default chunk size.

See Also:

Constant Field Values

DEFAULT_ROOT

public static final String DEFAULT_ROOT

The suffix for the files collection.

See Also:

Constant Field Values

FILES_SUFFIX

public static final String FILES_SUFFIX

The suffix for the files collection.

See Also:

Constant Field Values

Constructor Detail

GridFs

public GridFs(MongoDatabase database)

Creates a new GridFs.

The GridFS objects will be stored in the 'fs' collection.

Parameters:

database - The database containing the GridFS collections.

GridFs

public GridFs(MongoDatabase database,
      String rootName)

Creates a new GridFs.

Parameters:

database - The database containing the GridFS collections.

rootName - The rootName for the collections. The FILES_SUFFIX and CHUNKS_SUFFIX will be appended to create the two collection names.

GridFs

public GridFs(String mongoDbUri)

Creates a new GridFs.

Parameters:

mongoDbUri - The configuration for the connection to MongoDB expressed as a MongoDB URL.

Throws:

IllegalArgumentException - If the mongoDbUri is not a properly formated MongoDB style URL.

See Also:

MongoDB Connections

GridFs

public GridFs(String mongoDbUri,
      String rootName)

Creates a new GridFs.

Parameters:

mongoDbUri - The configuration for the connection to MongoDB expressed as a MongoDB URL.

rootName - The rootName for the collections. The FILES_SUFFIX and CHUNKS_SUFFIX will be appended to create the two collection names.

Throws:

IllegalArgumentException - If the mongoDbUri is not a properly formated MongoDB style URL.

See Also:

MongoDB Connections

Method Detail

getChunkSize

public int getChunkSize()

Returns the size for a chunk written.

Returns:

The size for a chunk written.

read

public void read(String name,
        OutputStream sink)
          throws IOException

Reads a file from the GridFS collections and writes the contents to the sink

Parameters:

name - The name of the file.

sink - The stream to Write the data to.

Throws:

IOException - On a failure reading the data from MongoDB or writing to the sink.

setChunkSize

public void setChunkSize(int chunkSize)

Sets the value of size for a chunk written.

Parameters:

chunkSize - The new value for the size for a chunk written.

unlink

public boolean unlink(String name)
               throws IOException

Unlinks (deletes) the file from the GridFS collections.

Parameters:

name - The name of the file to be deleted.

Returns:

True if a file was deleted, false otherwise.

Throws:

IOException - On a failure to delete the file.

write

public void write(String name,
         InputStream source)
           throws IOException

Attempts to write a file into the GridFS collections using the specified name for the file and deriving the chunks from the data read from the source.

Parameters:

name - The name of the file being written.

source - The source of the bits in the file.

Throws:

IOException - On a failure writing the documents or reading the file contents. In the case of a failure an attempt is made to remove the documents written to the collections.