From 4d471839a80b397c844d7fb365171d9e5f480dc7 Mon Sep 17 00:00:00 2001
From: "Mateusz \"Serafin\" Gajewski" <github@wendigo.pl>
Date: Fri, 22 Nov 2024 15:28:37 +0100
Subject: [PATCH] Add per-jdk version configuration support

---
 src/main/go/args/java_execution.go      | 35 +++++++++++++++++++++++++
 src/main/go/args/java_execution_test.go | 29 ++++++++++++++++++++
 src/main/go/args/java_static_config.go  | 10 +++++++
 3 files changed, 74 insertions(+)
 create mode 100644 src/main/go/args/java_execution_test.go
 create mode 100644 src/main/go/args/java_static_config.go

diff --git a/src/main/go/args/java_execution.go b/src/main/go/args/java_execution.go
index 1e7ca8d..ba12eee 100644
--- a/src/main/go/args/java_execution.go
+++ b/src/main/go/args/java_execution.go
@@ -6,6 +6,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"runtime"
 	"strings"
 )
@@ -14,6 +15,30 @@ func getArchSpecificDirectory() string {
 	return fmt.Sprintf("%s-%s", runtime.GOOS, runtime.GOARCH)
 }
 
+func DetectJvmVersion(javaBin string) (string, error) {
+	command := exec.Command(javaBin, "-version")
+	output, err := command.CombinedOutput()
+	if err != nil {
+		return "", fmt.Errorf("could not exec java to determine jvm version: %w", err)
+	}
+
+	return ExtractJvmVersion(string(output))
+}
+
+func ExtractJvmVersion(output string) (string, error) {
+	regex := regexp.MustCompile("version \"(.*)\"")
+	matches := regex.FindStringSubmatch(output)
+	if len(matches) != 2 {
+		return "", fmt.Errorf("unrecognized java version output: %s", output)
+	}
+	return matches[1], nil
+}
+
+func GetMajorJavaVersion(javaVersion string) string {
+	components := strings.Split(javaVersion, ".")
+	return components[0]
+}
+
 func (options *Options) JavaExecution(daemonize bool) ([]string, []string, error) {
 	var javaBin = "java"
 
@@ -27,6 +52,11 @@ func (options *Options) JavaExecution(daemonize bool) ([]string, []string, error
 		javaBin = filepath.Join(options.JvmDir, "bin/java")
 	}
 
+	jdkVersion, err := DetectJvmVersion(javaBin)
+	if err != nil {
+		return nil, nil, err
+	}
+
 	properties := make(map[string]string)
 	for k, v := range options.SystemProperties {
 		properties[k] = v
@@ -61,6 +91,11 @@ func (options *Options) JavaExecution(daemonize bool) ([]string, []string, error
 
 	command := []string{javaBin, "-cp", classpath}
 	command = append(command, options.JvmConfig...)
+
+	if perJdkConfig, exists := jvmSpecificConfig[GetMajorJavaVersion(jdkVersion)]; exists {
+		command = append(command, perJdkConfig...)
+	}
+
 	if len(options.JvmOptions) != 0 {
 		command = append(command, strings.Join(options.JvmOptions, " "))
 	}
diff --git a/src/main/go/args/java_execution_test.go b/src/main/go/args/java_execution_test.go
new file mode 100644
index 0000000..89b03f4
--- /dev/null
+++ b/src/main/go/args/java_execution_test.go
@@ -0,0 +1,29 @@
+package args
+
+import "testing"
+
+func TestParsingJvmVersion(t *testing.T) {
+	testCases := []struct {
+		output          string
+		expectedVersion string
+	}{
+		{
+			output:          "openjdk version \"24-ea\" 2025-03-18\nOpenJDK Runtime Environment (build 24-ea+24-2960)\nOpenJDK 64-Bit Server VM (build 24-ea+24-2960, mixed mode, sharing)",
+			expectedVersion: "24-ea",
+		},
+		{
+			output:          "openjdk version \"23\" 2024-09-17\nOpenJDK Runtime Environment Temurin-23+37 (build 23+37)\nOpenJDK 64-Bit Server VM Temurin-23+37 (build 23+37, mixed mode, sharing)",
+			expectedVersion: "23",
+		},
+	}
+
+	for _, testCase := range testCases {
+		actualVersion, err := ExtractJvmVersion(testCase.output)
+		if err != nil {
+			t.Fatalf("Unexpected error while extracting JVM version: %v", err)
+		}
+		if actualVersion != testCase.expectedVersion {
+			t.Fatalf("Expected Java version %s for output %s", testCase.expectedVersion, testCase.output)
+		}
+	}
+}
diff --git a/src/main/go/args/java_static_config.go b/src/main/go/args/java_static_config.go
new file mode 100644
index 0000000..dfd4420
--- /dev/null
+++ b/src/main/go/args/java_static_config.go
@@ -0,0 +1,10 @@
+package args
+
+const vectorApiIncubating = "--add-modules=jdk.incubator.vector"
+
+var jvmSpecificConfig = map[string][]string{
+	"22": {vectorApiIncubating},
+	"23": {vectorApiIncubating},
+	// 24 is not released yet, but vector API will be still incubating
+	"24": {vectorApiIncubating},
+}