Update to Java 21 (Long-term support LTS)

Author: JohT

.github/workflows/public-analyze-code-graph.yml

@@ -71,7 +71,7 @@ jobs:
       matrix:
         include:
         - os: ubuntu-22.04
-          java: 17
+          java: 21
           python: 3.12
           miniforge: 24.9.0-0
     steps:

COMMANDS.md

@@ -78,7 +78,7 @@ a profile, the newest versions will be used. Other profiles can be found in the
 
 ### Notes
 
-- Be sure to use Java 17 for Neo4j v5 and Java 11 for Neo4j v4
+- Be sure to use Java 21 for Neo4j v5 and Java 11 for Neo4j v4
 - Use your own initial Neo4j password
 - For more details have a look at the script [analyze.sh](./scripts/analysis/analyze.sh)
 

README.md

@@ -25,6 +25,10 @@ Contained within this repository is a comprehensive and automated code graph ana
 - Example analysis for [AxonFramework](https://github.com/AxonFramework/AxonFramework)
 - Example analysis for [react-router](https://github.com/remix-run/react-router)
 
+### :newspaper: News
+
+- April 2025: Migrated to Java 21 in preparation for [Neo4j 2025.x](https://neo4j.com/docs/upgrade-migration-guide/current/version-2025/upgrade).
+
 ### :notebook: Jupyter Notebook Reports
 
 Here is an overview of [Jupyter Notebooks](https://jupyter.org) reports from [code-graph-analysis-examples](https://github.com/JohT/code-graph-analysis-examples). For a complete list, see the [Jupyter Notebook Report Reference](#page_with_curl-jupyter-notebook-report-reference).
@@ -66,7 +70,7 @@ Here are some fully automated graph visualizations utilizing [GraphViz](https://
 
 ## :hammer_and_wrench: Prerequisites
 
-- Java 17 is [required for Neo4j](https://neo4j.com/docs/operations-manual/current/installation/requirements/#deployment-requirements-software) (Neo4j 5.x requirement).
+- Java 21 is [required for Neo4j 2025.x](https://neo4j.com/docs/operations-manual/current/installation/requirements/#deployment-requirements-software). See also [Changes from Neo4j 5 to 2025.x](https://neo4j.com/docs/upgrade-migration-guide/current/version-2025/upgrade).
 - On Windows it is recommended to use the git bash provided by [git for windows](https://github.com/git-guides/install-git#install-git-on-windows).
 - [jq](https://github.com/jqlang/jq) the "lightweight and flexible command-line JSON processor" needs to be installed. Latest releases: https://github.com/jqlang/jq/releases/latest. Check using `jq --version`.
 - Set environment variable `NEO4J_INITIAL_PASSWORD` to a password of your choice. For example: