Package org.wikidata.wdtk.dumpfiles

Class MwLocalDumpFile

java.lang.Object

org.wikidata.wdtk.dumpfiles.MwLocalDumpFile

All Implemented Interfaces:

MwDumpFile

public class MwLocalDumpFile
extends java.lang.Object
implements MwDumpFile

Class for representing dump files that are found at arbitrary (local) file paths. The meta-data for the dump file (content type, time stamp, etc.) can be set explicitly, or be guessed from the file name (to the extent possible).

Author:

Markus Damm, Markus Kroetzsch

Nested Class Summary

Nested classes/interfaces inherited from interface org.wikidata.wdtk.dumpfiles.MwDumpFile

MwDumpFile.DateComparator

Constructor Summary

Constructors

Constructor	Description
MwLocalDumpFile(java.lang.String filepath)	Constructor.
MwLocalDumpFile(java.lang.String filePath, DumpContentType dumpContentType, java.lang.String dateStamp, java.lang.String projectName)	Constructor.

Method Summary

Modifier and Type	Method	Description
java.lang.String	getDateStamp()	Returns the date stamp for this dump.
DumpContentType	getDumpContentType()	Returns information about the content of the dump.
java.io.BufferedReader	getDumpFileReader()	Returns a buffered reader that provides access to the (uncompressed) text content of the dump file.
java.io.InputStream	getDumpFileStream()	Returns an input stream that provides access to the (uncompressed) text content of the dump file.
java.nio.file.Path	getPath()	Returns the absolute path to this dump file.
java.lang.String	getProjectName()	Returns the project name for this dump.
boolean	isAvailable()	Checks if the dump is actually available.
void	prepareDumpFile()	Prepares the dump file for access via MwDumpFile.getDumpFileStream() or MwDumpFile.getDumpFileReader().
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

MwLocalDumpFile

public MwLocalDumpFile(java.lang.String filepath)

Constructor. The DumpContentType will be inferred by the name of the file, if possible. If it is not possible, it will be set to JSON by default.

Parameters:

filepath - Path to the dump file in the file system

MwLocalDumpFile

public MwLocalDumpFile(java.lang.String filePath,
                       DumpContentType dumpContentType,
                       java.lang.String dateStamp,
                       java.lang.String projectName)

Constructor.

Parameters:

filePath - Path to the dump file in the file system

dumpContentType - DumpContentType of the dump file, or null if not known to guess it from file name; this information is essential to invoke the correct processing code to read the dump file

dateStamp - dump date in format YYYYMMDD, or null if not known to guess it from file name; this is mainly used for logs and messages

projectName - project name string, or null to use a default string; this is mainly used for logs and messages

Method Detail

getPath

public java.nio.file.Path getPath()

Returns the absolute path to this dump file.

Returns:

path

isAvailable

public boolean isAvailable()

Description copied from interface: MwDumpFile

Checks if the dump is actually available. Should be called before MwDumpFile.getDumpFileReader(). Depending on the type of dumpfile, this will trigger one or more checks to make sure that all relevant data can be accessed for this dump file. This is still no definite guarantee that the download will succeed, since there can always be IO errors anyway, but it helps to detect cases where the dump is clearly not in a usable state.

Specified by:

isAvailable in interface MwDumpFile

Returns:

true if the dump file is likely to be available

getProjectName

public java.lang.String getProjectName()

Description copied from interface: MwDumpFile

Returns the project name for this dump. Together with the dump content type and date stamp, this identifies the dump, and it is therefore always available.

Specified by:

getProjectName in interface MwDumpFile

Returns:

a project name string

getDateStamp

public java.lang.String getDateStamp()

Description copied from interface: MwDumpFile

Returns the date stamp for this dump. Together with the project name and dump content type, this identifies the dump, and it is therefore always available.

Specified by:

getDateStamp in interface MwDumpFile

Returns:

a string that represents a date in format YYYYMMDD

getDumpContentType

public DumpContentType getDumpContentType()

Description copied from interface: MwDumpFile

Returns information about the content of the dump. Together with the project name and date stamp, this identifies the dump, and it is therefore always available.

Specified by:

getDumpContentType in interface MwDumpFile

Returns:

the content type of this dump

getDumpFileStream

public java.io.InputStream getDumpFileStream()
                                      throws java.io.IOException

Description copied from interface: MwDumpFile

Returns an input stream that provides access to the (uncompressed) text content of the dump file.

It is important to close the stream after use.

Specified by:

getDumpFileStream in interface MwDumpFile

Returns:

an input stream to read the dump file

Throws:

java.io.IOException - if the dump file contents could not be accessed

getDumpFileReader

public java.io.BufferedReader getDumpFileReader()
                                         throws java.io.IOException

Description copied from interface: MwDumpFile

Returns a buffered reader that provides access to the (uncompressed) text content of the dump file.

It is important to close the reader after use.

Specified by:

getDumpFileReader in interface MwDumpFile

Returns:

a buffered reader to read the dump file

Throws:

java.io.IOException - if the dump file contents could not be accessed

prepareDumpFile

public void prepareDumpFile()

Description copied from interface: MwDumpFile

Prepares the dump file for access via MwDumpFile.getDumpFileStream() or MwDumpFile.getDumpFileReader(). In particular, this will download any remote files.

Specified by:

prepareDumpFile in interface MwDumpFile

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object