it.unimi.di.mg4j.io
Interface IOFactory

All Known Implementing Classes:

HadoopFileSystemIOFactory

public interface IOFactory

A factory for streams.

Instances of this factory are used to make (at least partially) index construction and access independent of the file system implementation. For instance, FILESYSTEM_FACTORY provides methods that are equivalent to standard Java file handling, whereas HadoopFileSystemIOFactory makes it possible to use a Hadoop file system like HDFS to build indices.

Warning: I/O factories were introduced in 5.1, and they are still somewhat experimental. Some parts of the code of MG4J might still open directly files using java.io's methods instead of factory methods. Please report issues and inconsistent behaviour.

Since:

5.1

Author:

Sebastiano Vigna

Field Summary

static IOFactory

FILESYSTEM_FACTORY

Method Summary

void	createNewFile(String name)
boolean	delete(String name)
boolean	exists(String name)
InputStream	getInputStream(String name)
OutputStream	getOutputStream(String name)
ReadableByteChannel	getReadableByteChannel(String name)
WritableByteChannel	getWritableByteChannel(String name)
long	length(String name)

Field Detail

FILESYSTEM_FACTORY

static final IOFactory FILESYSTEM_FACTORY

Method Detail

getInputStream

InputStream getInputStream(String name)
                           throws IOException

Throws:

IOException

getOutputStream

OutputStream getOutputStream(String name)
                             throws IOException

Throws:

IOException

getWritableByteChannel

WritableByteChannel getWritableByteChannel(String name)
                                           throws IOException

Throws:

IOException

getReadableByteChannel

ReadableByteChannel getReadableByteChannel(String name)
                                           throws IOException

Throws:

IOException

exists

boolean exists(String name)
               throws IOException

Throws:

IOException

delete

boolean delete(String name)
               throws IOException

Throws:

IOException

createNewFile

void createNewFile(String name)
                   throws IOException

Throws:

IOException

length

long length(String name)
            throws IOException

Throws:

IOException