[ci] JDK matrix Buildkite pipelines (pt 2/Windows)

This commit adds JDK matrix Buildkite pipelines for Windows 2022, 2019
and 2016.

Relates:

- elastic#15539
- elastic/ingest-dev#1725 (comment)

.buildkite/scripts/jdk-matrix-tests/generate-steps.py

@@ -60,7 +60,7 @@ def init_annotation(self) -> JobRetValues:
         Command for creating the header of a new annotation for a group step
         """
 
-        body = f"### Group: `{self.os} / {self.jdk}`\n| **Status** | **Test** |\n| --- | ----|"
+        body = f"### Group: {self.os} / {self.jdk}\n| **Status** | **Test** |\n| --- | ----|"
 
         return JobRetValues(
             step_label="Initialize annotation",
@@ -81,21 +81,23 @@ def __init__(self, os: str, jdk: str, group_key: str):
 
     def all_jobs(self):# -> list[Callable[[], JobRetValues]]:
         return [
+          self.init_annotation,
           self.unit_tests,
         ]
 
     def unit_tests(self) -> JobRetValues:
-        step_name_human = "Java Unit Test"
-        test_command = "# TODO"
+        step_name_human = "Unit Test"
+        step_key = f"{self.group_key}-unit-test"
+        test_command = f'''.\\\\.buildkite\\\\scripts\\\\jdk-matrix-tests\\\\launch-command.ps1 -JDK "{self.jdk}" -StepNameHuman "{step_name_human}" -Context "{self.group_key}" -CIScript ".\\\\ci\\\\unit_tests.bat"
+        '''
 
         return JobRetValues(
             step_label=step_name_human,
-            command=test_command,
-            step_key="java-unit-test",
-            depends="",
+            command=LiteralScalarString(test_command),
+            step_key=step_key,
+            depends=self.init_annotation_key,
         )
-        return step_name_human, test_command
-
+
 
 class LinuxJobs(Jobs):
     def __init__(self, os: str, jdk: str, group_key: str):

.buildkite/scripts/jdk-matrix-tests/launch-command.ps1

@@ -0,0 +1,34 @@
+# ********************************************************
+# This file contains prerequisite bootstrap invocations
+# required for Logstash CI JDK matrix tests
+# ********************************************************
+
+$ErrorActionPreference = "Stop"
+
+param (
+    [string]$JDK,
+    [string]$CIScript,
+    [switch]$StepNameHuman,
+    [switch]$AnnotateContext
+)
+
+# unset generic JAVA_HOME
+if (Test-Path env:JAVA_HOME) {
+    Remove-Item -Path env:JAVA_HOME
+    Write-Host "--- Environment variable 'JAVA_HOME' has been unset."
+} else {
+    Write-Host "--- Environment variable 'JAVA_HOME' doesn't exist. Continuing."
+}
+
+# LS env vars for JDK matrix tests
+$JAVA_CUSTOM_DIR = "C:\.java\$JDK"
+$env:BUILD_JAVA_HOME = $JAVA_CUSTOM_DIR
+$env:RUNTIME_JAVA_HOME = $JAVA_CUSTOM_DIR
+$env:LS_JAVA_HOME = $JAVA_CUSTOM_DIR
+
+& $CIScript
+if ($LASTEXITCODE -ne 0) {
+    buildkite-agent annotate --context=$AnnotateContext --append "| :bk-status-failed: | $StepNameHuman |\n"
+    exit 1 
+}
+buildkite-agent annotate --context=$AnnotateContext --append "| :bk-status-passed: | $StepNameHuman |\n"

.buildkite/windows_jdk_matrix_pipeline.yml

@@ -1,3 +1,65 @@
 steps:
-  - label: "Test Windows JDK matrix pipeline"
-    command: "echo 'Hello world'"
+  - input: "Test Parameters"
+    if: build.source != "schedule"
+    fields:
+      - select: "Operating System"
+        key: "matrix-os"
+        hint: "The operating system variant(s) to run on:"
+        required: true
+        multiple: true
+        default: "windows-2022"
+        options:
+          - label: "Windows 2022"
+            value: "windows-2022"
+          - label: "Windows 2019"
+            value: "windows-2019"
+          - label: "Windows 2016"
+            value: "windows-2016"
+
+      - select: "Java"
+        key: "matrix-jdk"
+        hint: "The JDK to test with:"
+        required: true
+        multiple: true
+        default: "adoptiumjdk_17"
+        options:
+          - label: "Adoptium JDK 17 (Eclipse Temurin)"
+            value: "adoptiumjdk_17"
+          - label: "Adopt OpenJDK 11"
+            value: "adoptopenjdk_11"
+          - label: "OpenJDK 17"
+            value: "openjdk_17"
+          - label: "OpenJDK 11"
+            value: "openjdk_11"
+          - label: "Zulu 17"
+            value: "zulu_17"
+          - label: "Zulu 11"
+            value: "zulu_11"
+
+  - wait: ~
+    if: build.source != "schedule"
+
+  - command: |
+      set -euo pipefail
+
+      echo "--- Downloading prerequisites"
+      python3 -m pip install ruamel.yaml
+
+      echo "--- Printing generated dynamic steps"
+      export MATRIX_OSES="$(buildkite-agent meta-data get matrix-os)"
+      export MATRIX_JDKS="$(buildkite-agent meta-data get matrix-jdk)"
+      set +eo pipefail
+      python3 .buildkite/scripts/jdk-matrix-tests/generate-steps.py >pipeline_steps.yml
+      if [[ $$? -ne 0 ]]; then
+        echo "^^^ +++"
+        echo "There was a problem rendering the pipeline steps."
+        cat pipeline_steps.yml
+        echo "Exiting now."
+        exit 1
+      else
+        set -eo pipefail
+        cat pipeline_steps.yml
+      fi
+
+      echo "--- Uploading steps to buildkite"
+      cat pipeline_steps.yml | buildkite-agent pipeline upload