org.nees.data.store.permanent
Class LocalFileStorage

java.lang.Object
  org.nees.data.store.permanent.LocalFileStorage

All Implemented Interfaces:

InstantiationContractInterface, PermanentStorageInterface

public class LocalFileStorage

extends java.lang.Object

implements PermanentStorageInterface

Author:

USER

Field Summary

static java.lang.String

LOCAL_FILE_STORAGE_ROOT_KEY

Fields inherited from interface org.nees.data.store.permanent.PermanentStorageInterface

__CLASS_KEY, __IO_KEY

Constructor Summary

LocalFileStorage()
Creates a new instance of LocalFileStorage

Method Summary

void	append(java.net.URI tailURI, java.net.URI headURI) Binary concatenate of the tail file to the head.
void	copy(java.net.URI sourceURI, java.net.URI targetURI, boolean overwriteOK) Copies the existing source to the target, overwriting the target if specified.
java.net.URI	createNewEntryURI(LogicalName logicalName, int version) This just creates the name, but does not validate it, beyond basic correctness, so whether this exists or not must be checked elsewhere.
boolean	delete(java.net.URI targetURI) Remove an entry from this store.
boolean	exists(java.net.URI targetURI) This returns a true if the specified target exists in this store.
java.io.File	getRepoRootDirectory()
void	initialize(java.util.Properties p, InitializationObjectInterface ioi)
void	isValidLogicalname(LogicalName logicalName) TODO This needs to have something more comprehensive in the way of checking.
java.io.File	logicalNameToFile(LogicalName ln, java.lang.String suffix) This will take a logical name and change it into either a path representation on the local file system or create a hash of it.
long	size(java.net.URI targetURI) The size of the entry in bytes.

Methods inherited from class java.lang.Object

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

Field Detail

LOCAL_FILE_STORAGE_ROOT_KEY

public static java.lang.String LOCAL_FILE_STORAGE_ROOT_KEY

Constructor Detail

LocalFileStorage

public LocalFileStorage()

Creates a new instance of LocalFileStorage

Method Detail

copy

public void copy(java.net.URI sourceURI,
                 java.net.URI targetURI,
                 boolean overwriteOK)
          throws NFMSException

Description copied from interface: PermanentStorageInterface

Copies the existing source to the target, overwriting the target if specified. If the target exists and the overwriteOK flag is false then an exception is thrown. The append flag supercedes the overwrite flag.

Specified by:

copy in interface PermanentStorageInterface

Throws:

NFMSException

delete

public boolean delete(java.net.URI targetURI)
               throws NFMSException

Description copied from interface: PermanentStorageInterface

Remove an entry from this store. This is a true delete and the file is then completely removed.

Specified by:

delete in interface PermanentStorageInterface

Throws:

NFMSException

exists

public boolean exists(java.net.URI targetURI)
               throws NFMSException

Description copied from interface: PermanentStorageInterface

This returns a true if the specified target exists in this store.

Specified by:

exists in interface PermanentStorageInterface

Throws:

NFMSException

createNewEntryURI

public java.net.URI createNewEntryURI(LogicalName logicalName,
                                      int version)
                               throws NFMSException

This just creates the name, but does not validate it, beyond basic correctness, so whether this exists or not must be checked elsewhere.

Specified by:

createNewEntryURI in interface PermanentStorageInterface

Throws:

NFMSException

initialize

public void initialize(java.util.Properties p,
                       InitializationObjectInterface ioi)
                throws java.lang.Exception

Specified by:

initialize in interface InstantiationContractInterface

Throws:

java.lang.Exception

size

public long size(java.net.URI targetURI)
          throws NFMSException

Description copied from interface: PermanentStorageInterface

The size of the entry in bytes.

Specified by:

size in interface PermanentStorageInterface

Throws:

NFMSException

append

public void append(java.net.URI tailURI,
                   java.net.URI headURI)
            throws NFMSException

Description copied from interface: PermanentStorageInterface

Binary concatenate of the tail file to the head. Note that the target does not need to exist in which case this has the same functionality as the copy command.

Specified by:

append in interface PermanentStorageInterface

Throws:

NFMSException

getRepoRootDirectory

public java.io.File getRepoRootDirectory()
                                  throws NFMSException

Throws:

NFMSException

isValidLogicalname

public void isValidLogicalname(LogicalName logicalName)
                        throws NFMSIllegalLogicalNameException

TODO This needs to have something more comprehensive in the way of checking. Now it just checks that the path is valid on the system.

Specified by:

isValidLogicalname in interface PermanentStorageInterface

Throws:

NFMSIllegalLogicalNameException

logicalNameToFile

public java.io.File logicalNameToFile(LogicalName ln,
                                      java.lang.String suffix)
                               throws NFMSException

This will take a logical name and change it into either a path representation on the local file system or create a hash of it. If these two operations fail, then an exception is thrown. The failure modes are related to the underlying storage mechanism, specifically that most operating systems have a maximum length for the full path and it is possible to exceed this (hence the fallback position of making a hash). There could also be other failures beyond the control of the JVM (mounted drives vanishing and such). Suffice to say that every logical name can be munged into a platform neutral format, but there are still file system vagaries to contend with.

Throws:

NFMSException