org.apache.nutch.fs
Class LocalFileSystem

java.lang.Object
  org.apache.nutch.fs.NutchFileSystem
      org.apache.nutch.fs.LocalFileSystem

public class LocalFileSystem

extends NutchFileSystem

Implement the NutchFileSystem interface for the local disk. This is pretty easy. The interface exists so we can use either remote or local Files very easily.

Author:

Mike Cafarella

Field Summary

Fields inherited from class org.apache.nutch.fs.NutchFileSystem

LOG

Constructor Summary

LocalFileSystem()

Method Summary

void	close() Shut down the FS.
void	completeLocalInput(File localFile) We're done reading.
void	completeLocalOutput(File nfsWorkingFile, File tmpLocalFile) It's in the right place - nothing to do.
void	copyFromLocalFile(File src, File dst) Similar to moveFromLocalFile(), except the source is kept intact.
void	copyToLocalFile(File src, File dst) We can't delete the src file in this case.
NFSOutputStream	create(File f) Create the file at f.
NFSOutputStream	create(File f, boolean overwrite)
boolean	delete(File f) Get rid of File f, whether a true file or dir.
boolean	exists(File f) Check if exists
long	getLength(File f)
String	getName() Returns a name for this filesystem, suitable to pass to NutchFileSystem.getNamed(String).
boolean	isDirectory(File f)
File[]	listFiles(File f)
void	lock(File f, boolean shared) Obtain a filesystem lock at File f.
void	mkdirs(File f) Make the given file and all non-existent parents into directories.
void	moveFromLocalFile(File src, File dst) In the case of the local filesystem, we can just rename the file.
NFSInputStream	open(File f) Open the file at f
void	release(File f) Release a held lock
boolean	rename(File src, File dst) Rename files/dirs
File	startLocalInput(File nfsInputFile, File tmpLocalFile) We can read directly from the real local fs.
File	startLocalOutput(File nfsOutputFile, File tmpLocalFile) We can write output directly to the final location
String	toString()

Methods inherited from class org.apache.nutch.fs.NutchFileSystem

createNewFile, get, getNamed, isFile, listFiles, parseArgs

Methods inherited from class java.lang.Object

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

Constructor Detail

LocalFileSystem

public LocalFileSystem()
                throws IOException

Method Detail

getName

public String getName()

Description copied from class: NutchFileSystem

Returns a name for this filesystem, suitable to pass to NutchFileSystem.getNamed(String).

Specified by:

getName in class NutchFileSystem

open

public NFSInputStream open(File f)
                    throws IOException

Open the file at f

Specified by:

open in class NutchFileSystem

Throws:

IOException

create

public NFSOutputStream create(File f)
                       throws IOException

Create the file at f.

Specified by:

create in class NutchFileSystem

Throws:

IOException

create

public NFSOutputStream create(File f,
                              boolean overwrite)
                       throws IOException

Specified by:

create in class NutchFileSystem

Throws:

IOException

rename

public boolean rename(File src,
                      File dst)
               throws IOException

Rename files/dirs

Specified by:

rename in class NutchFileSystem

Throws:

IOException

delete

public boolean delete(File f)
               throws IOException

Get rid of File f, whether a true file or dir.

Specified by:

delete in class NutchFileSystem

Throws:

IOException

exists

public boolean exists(File f)
               throws IOException

Description copied from class: NutchFileSystem

Check if exists

Specified by:

exists in class NutchFileSystem

Throws:

IOException

isDirectory

public boolean isDirectory(File f)
                    throws IOException

Specified by:

isDirectory in class NutchFileSystem

Throws:

IOException

getLength

public long getLength(File f)
               throws IOException

Specified by:

getLength in class NutchFileSystem

Throws:

IOException

listFiles

public File[] listFiles(File f)
                 throws IOException

Specified by:

listFiles in class NutchFileSystem

Throws:

IOException

mkdirs

public void mkdirs(File f)
            throws IOException

Description copied from class: NutchFileSystem

Make the given file and all non-existent parents into directories.

Specified by:

mkdirs in class NutchFileSystem

Throws:

IOException

lock

public void lock(File f,
                 boolean shared)
          throws IOException

Obtain a filesystem lock at File f.

Specified by:

lock in class NutchFileSystem

Throws:

IOException

release

public void release(File f)
             throws IOException

Release a held lock

Specified by:

release in class NutchFileSystem

Throws:

IOException

moveFromLocalFile

public void moveFromLocalFile(File src,
                              File dst)
                       throws IOException

In the case of the local filesystem, we can just rename the file.

Specified by:

moveFromLocalFile in class NutchFileSystem

Throws:

IOException

copyFromLocalFile

public void copyFromLocalFile(File src,
                              File dst)
                       throws IOException

Similar to moveFromLocalFile(), except the source is kept intact.

Specified by:

copyFromLocalFile in class NutchFileSystem

Throws:

IOException

copyToLocalFile

public void copyToLocalFile(File src,
                            File dst)
                     throws IOException

We can't delete the src file in this case. Too bad.

Specified by:

copyToLocalFile in class NutchFileSystem

Throws:

IOException

startLocalOutput

public File startLocalOutput(File nfsOutputFile,
                             File tmpLocalFile)
                      throws IOException

We can write output directly to the final location

Specified by:

startLocalOutput in class NutchFileSystem

Throws:

IOException

completeLocalOutput

public void completeLocalOutput(File nfsWorkingFile,
                                File tmpLocalFile)
                         throws IOException

It's in the right place - nothing to do.

Specified by:

completeLocalOutput in class NutchFileSystem

Throws:

IOException

startLocalInput

public File startLocalInput(File nfsInputFile,
                            File tmpLocalFile)
                     throws IOException

We can read directly from the real local fs.

Specified by:

startLocalInput in class NutchFileSystem

Throws:

IOException

completeLocalInput

public void completeLocalInput(File localFile)
                        throws IOException

We're done reading. Nothing to clean up.

Specified by:

completeLocalInput in class NutchFileSystem

Throws:

IOException

close

public void close()
           throws IOException

Shut down the FS. Not necessary for regular filesystem.

Specified by:

close in class NutchFileSystem

Throws:

IOException

toString

public String toString()