ca.uhn.hl7v2.util.idgenerator

Class FileBasedGenerator

java.lang.Object

ca.uhn.hl7v2.util.idgenerator.IDGenerator.OrderedSupport

ca.uhn.hl7v2.util.idgenerator.InMemoryIDGenerator

ca.uhn.hl7v2.util.idgenerator.FileBasedGenerator

All Implemented Interfaces:

IDGenerator, IDGenerator.Ordered

public class FileBasedGenerator
extends InMemoryIDGenerator

Replacement for MessageIDGenerator. You should not use this class directly, however, but wrap it into a DelegatingHiLoGenerator generator. Its primary improvement over MessageIDGenerator is that you can set path and file name.

Reading and writing to the file is thread-safe, however, you should not use the same file from different Java processes because no read/write locks are being checked.

Nested Class Summary

Nested classes/interfaces inherited from interface ca.uhn.hl7v2.util.idgenerator.IDGenerator

IDGenerator.Ordered, IDGenerator.OrderedSupport

Constructor Summary

Constructors

Constructor and Description
FileBasedGenerator()

Method Summary

Modifier and Type	Method and Description
String	getID() Generates and returns a new ID.
void	reset()
void	setDirectory(String directory)
void	setFileName(String fileName)
void	setMinimizeReads(boolean theMinimizeReads) If set to true (default is false) the generator minimizes the number of disk reads by caching the last read value.
void	setNeverFail(boolean neverFail) If set to false (default is true), retrieving a new ID may fail if the ID file in the home directory can not be written/read.

Methods inherited from class ca.uhn.hl7v2.util.idgenerator.InMemoryIDGenerator

set

Methods inherited from class ca.uhn.hl7v2.util.idgenerator.IDGenerator.OrderedSupport

getIncrement

Methods inherited from class java.lang.Object

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

Constructor Detail

FileBasedGenerator

public FileBasedGenerator()

Method Detail

getID

public String getID()
             throws IOException

Description copied from interface: IDGenerator

Generates and returns a new ID. Note: This method must be implemented to be thread-safe.

Specified by:

getID in interface IDGenerator

Overrides:

getID in class InMemoryIDGenerator

Returns:

a new ID.

Throws:

IOException

setDirectory

public void setDirectory(String directory)

setFileName

public void setFileName(String fileName)

setMinimizeReads

public void setMinimizeReads(boolean theMinimizeReads)

If set to true (default is false) the generator minimizes the number of disk reads by caching the last read value. This means one less disk read per X number of IDs generated, but also means that multiple instances of this generator may clobber each other's values.

setNeverFail

public void setNeverFail(boolean neverFail)

If set to false (default is true), retrieving a new ID may fail if the ID file in the home directory can not be written/read. If set to true, failures will be ignored, which means that IDs may be repeated after a JVM restart.

reset

public void reset()

Specified by:

reset in interface IDGenerator.Ordered

Overrides:

reset in class InMemoryIDGenerator