More robust method to check for JDK

Author: BoykoAlex

Diff for: nodejs-packages/jvm-launch-utils/package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@pivotal-tools/jvm-launch-utils",
-  "version": "0.0.17",
+  "version": "0.0.18",
   "description": "Provides utilities useful for launching Java processes from node packages.",
   "files": [
     "src",
@@ -29,6 +29,7 @@
   "homepage": "https://github.com/spring-projects/sts4/nodejs-packages/jvm-launch-utils/README.md",
   "devDependencies": {
     "@types/node": "^16.6.0",
+    "ts-node": "^10.4.0",
     "typescript": "^4.2.4"
   }
 }

Diff for: nodejs-packages/jvm-launch-utils/package.json

@@ -181,7 +181,9 @@ class JVMImpl implements JVM {
         return this.javaExe;
     }
     isJdk(): boolean {
-        return FS.existsSync(Path.resolve(this.getJavaHome(), "jmods", "jdk.management.jmod"));
+        const javaExecutable = this.getJavaExecutable();
+        const str = ChildProcess.execSync(javaExecutable + ' --list-modules', {windowsHide: true, encoding: 'utf8'});
+        return str.search(/^jdk.management@.*$/m) >= 0;
     }
     jarLaunch(jar: string, vmargs?: [string], execFileOptions?: ChildProcess.ExecFileOptions): ChildProcess.ChildProcess {
         let args = [];