• Java Development Kit (JDK) 21 (LTS)

  • Windows suggested path: C:\Program Files\Java\jdk-21 (or similar jdk-21.x.x)
  • Verify:
    • PowerShell:

      java -version
      javac -version

    • If javac is missing, you installed a JRE instead of a JDK.

• Apache Maven 3.8+ (обычно ставится вместе с IDE плагином, но лучше установить отдельно)

  • Verify:

    mvn -v

• VS Code or Cursor with extensions:

  • Extension Pack for Java
  • Language Support for Java by Red Hat
  • Debugger for Java
  • Maven for Java
  • Project Manager for Java

1. Open Folder: open the project root (the folder containing pom.xml, src/, and .vscode/).
2. Trust the workspace if asked (otherwise Java extensions run in Restricted Mode).
3. Extensions will prompt to Import Maven Project — accept it.

Recommended: set JDK 21 in workspace settings so IntelliSense and debug use the same JDK.

Edit .vscode/settings.json (already present here):

{
  "java.configuration.updateBuildConfiguration": "automatic",
  "java.import.maven.enabled": true,
  "java.jdt.ls.java.home": "C:\\Program Files\\Java\\jdk-21",
  "java.configuration.runtimes": [
    { "name": "JavaSE-21", "path": "C:\\Program Files\\Java\\jdk-21", "default": true }
  ]
}

If your JDK path differs, adjust the path accordingly.

Additionally, this repo’s .vscode/launch.json and .vscode/tasks.json are configured to:

• run mvn package automatically before debug
• and enforce JAVA_HOME for debug launch if needed

PowerShell (Windows):

mvn -q -DskipTests package
mvn -q exec:java

1. Open src/main/java/io/example/calciteclickhouse/Main.java
2. Set a breakpoint in main
3. Press F5 and choose "Debug Main (CalciteTest)"
   • This will:
     • run Maven package as a preLaunchTask
     • start the app with the proper classpath
4. When stopped on breakpoint, use the Run and Debug view (Ctrl+Shift+D) to inspect variables and call stack.

If you see "invalid target release: 21": Maven/Java runs under an older JDK. Either:

• set system JAVA_HOME to JDK 21 and restart the IDE, or
• set JDK 21 for the task/launch env (already configured in .vscode), or
• temporarily set PowerShell env vars:

  $env:JAVA_HOME="C:\\Program Files\\Java\\jdk-21"
  $env:Path="$env:JAVA_HOME\\bin;$env:Path"

• Parses SQL with Calcite, converts to RelNode
• Runs a HepPlanner with rules (including a custom Filter→Project transpose rule)
• Prints SQL before/after optimization

Change the demo SQL in Main.java to experiment with different queries and rules.