Lucene Upgrader

This project attempts to make a single tool to upgrade Lucene indexes all the way through multiple versions. It does this by repackaging older versions of Lucene and using the IndexUpgrader tool from each version in turn.

Usage as a Library

Getting the dependency:

dependencies {
    implementation("org.trypticon.luceneupgrader:luceneupgrader:VERSION")
}

To upgrade an index all the way to version 8:

new IndexUpgrader(textIndexPath, null)
    .upgradeTo(LuceneVersion.VERSION_8);

The upgrade will be a no-op if the index is already at that version.

Upgrades can be done one step at a time by passing a different target version.

Usage of Command-Line Interface

Running the tool:

java -jar luceneupgrader-VERSION.jar

Given no additional arguments, the tool will output the available commands.

Building

To build and run all tests:

./gradlew build

To generate test Lucene indices, e.g. from one of the lucene subdirectories under testgen/:

../../gradlew runAll