org.dspace.app.util

Class IndexVersion

java.lang.Object

org.dspace.app.util.IndexVersion

public class IndexVersion
extends Object

This utility class simply determines the version of a given Solr/Lucene index, so that they can be upgraded to the latest version.

You must pass it the full path of the index directory, e.g. [dspace]/solr/statistics/data/index/

The response is simply a version number (e.g. 4.4), as this is utilized by the ant update_solr_indexes target in [src]/dspace/src/main/config/build.xml

Author:

tdonohue

Constructor Summary

Constructors

Constructor and Description
IndexVersion()

Method Summary

Modifier and Type	Method and Description
static int	compareSoftwareVersions(String firstVersion, String secondVersion) Compare two software version numbers to see which is greater.
static String	getIndexVersion(String indexDirPath) Determine the version of Solr/Lucene which was used to create a given index directory.
static String	getLatestVersion() Determine the version of Solr/Lucene which DSpace is currently running.
static void	main(String[] argv)

Methods inherited from class java.lang.Object

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

Constructor Detail

IndexVersion

public IndexVersion()

Method Detail

main

public static void main(String[] argv)
                 throws IOException

Throws:

IOException

getIndexVersion

public static String getIndexVersion(String indexDirPath)
                              throws IOException

Determine the version of Solr/Lucene which was used to create a given index directory.

Parameters:

indexDirPath - Full path of the Solr/Lucene index directory

Returns:

version as a string (e.g. "4.4"), empty string ("") if index directory is empty, or null if directory doesn't exist.

Throws:

IOException - if IO error

compareSoftwareVersions

public static int compareSoftwareVersions(String firstVersion,
                                          String secondVersion)
                                   throws IOException

Compare two software version numbers to see which is greater. ONLY does a comparison of *major* and *minor* versions (any sub-minor versions are stripped and ignored).

This method returns -1 if firstVersion is less than secondVersion, 1 if firstVersion is greater than secondVersion, and 0 if equal.

However, since we ignore sub-minor versions, versions "4.2.1" and "4.2.5" will be seen as EQUAL (as "4.2" = "4.2").

NOTE: In case it is not obvious, software version numbering does NOT behave like normal decimal numbers. For example, in software versions the following statement is TRUE: 4.1 < 4.4 < 4.5 < 4.10 < 4.21 < 4.51

Parameters:

firstVersion - First version to compare, as a String

secondVersion - Second version to compare as a String

Returns:

-1 if first less than second, 1 if first greater than second, 0 if equal

Throws:

IOException - if IO error

getLatestVersion

public static String getLatestVersion()

Determine the version of Solr/Lucene which DSpace is currently running. This is the latest version of Solr/Lucene which we can upgrade the index to.

Returns:

version as a string (e.g. "4.4")