improvements for resolving java home

packages/metals-languageclient/src/getJavaHome.ts

@@ -12,6 +12,7 @@ import { toPromise } from "./util";
 import fs from "fs";
 import path from "path";
 import { spawn } from "promisify-child-process";
+import { OutputChannel } from "./interfaces/OutputChannel";
 
 export type JavaVersion = "11" | "17" | "21";
 
@@ -26,44 +27,54 @@ export type JavaVersion = "11" | "17" | "21";
  * @param javaVersion metals.javaVersion value as read from the configuration or default
  */
 export async function getJavaHome(
- javaVersion: JavaVersion
+ javaVersion: JavaVersion,
+ outputChannel: OutputChannel
 ): Promise<string | undefined> {
- const fromEnvValue = await fromEnv(javaVersion);
+ const fromEnvValue = await fromEnv(javaVersion, outputChannel);
  return fromEnvValue ? fromEnvValue : await locate(javaVersion);
 }
 
 const versionRegex = /\d+\.\d+\.\d+/;
 async function validateJavaVersion(
  javaHome: string,
- javaVersion: JavaVersion
+ javaVersion: JavaVersion,
+ outputChannel: OutputChannel
 ): Promise<boolean> {
- const javaBins = [
- path.join(javaHome, "bin", "java"),
- path.join(javaHome, "bin", "java.exe"),
- path.join(javaHome, "bin", "jre", "java"),
- path.join(javaHome, "bin", "jre", "java.exe"),
- ].filter(fs.existsSync);
-
- if (javaBins.length != 0) {
- const javaBin = javaBins[0];
- const javaVersionOut = await spawn(javaBin, ["-version"], {
+ const javaBin = path.join(javaHome, "bin", "java");
+ try {
+ const javaVersionOut = spawn(javaBin, ["-version"], {
  encoding: "utf8",
  });
- const javaInfoStr = javaVersionOut.stderr as string;
+
+ javaVersionOut.stderr?.on("data", (out: Buffer) => {
+ outputChannel.appendLine(`${javaBin} -version:`);
+ const msg = out.toString().trim();
+ outputChannel.appendLine(msg);
+ });
+
+ const javaInfoStr = (await javaVersionOut).stderr as string;
  const matches = javaInfoStr.match(versionRegex);
  if (matches) {
- return matches[0].slice(0, 2) == javaVersion;
+ return +matches[0].slice(0, 2) >= +javaVersion;
  }
+ } catch (error) {
+ outputChannel.appendLine(`failed while running ${javaBin} -version`);
+ outputChannel.appendLine(`${error}`);
  }
  return false;
 }
 
 export async function fromEnv(
- javaVersion: JavaVersion
+ javaVersion: JavaVersion,
+ outputChannel: OutputChannel
 ): Promise<string | undefined> {
  const javaHome = process.env["JAVA_HOME"];
  if (javaHome) {
- const isValid = await validateJavaVersion(javaHome, javaVersion);
+ const isValid = await validateJavaVersion(
+ javaHome,
+ javaVersion,
+ outputChannel
+ );
  if (isValid) return javaHome;
  }
 
@@ -73,7 +84,7 @@ export async function fromEnv(
 function locate(javaVersion: JavaVersion): Promise<undefined | string> {
  return toPromise(
  pipe(
- locateJavaHome({ version: `~${javaVersion}` }),
+ locateJavaHome({ version: `>=${javaVersion}` }),
  chain((javaHomes) => {
  if (!javaHomes || javaHomes.length === 0) {
  return TE.right(undefined);

packages/metals-languageclient/src/setupCoursier.ts

@@ -52,7 +52,7 @@ export async function setupCoursier(
  const resolveJavaHomeWithCoursier = async (coursier: string) => {
  await run(
  coursier,
- ["java", "--jvm", javaVersion, "--setup"],
+ ["java", "--jvm", javaVersion, "-version"],
  handleOutput
  );
 
@@ -71,7 +71,7 @@ export async function setupCoursier(
  const coursier = await resolveCoursier();
  output.appendLine(`Using coursier located at ${coursier}`);
 
- var javaHome = await getJavaHome(javaVersion);
+ var javaHome = await getJavaHome(javaVersion, output);
 
  if (!javaHome) {
  output.appendLine(
@@ -100,7 +100,11 @@ export async function validateCoursier(
  };
 
  const validateDefault = async () => {
- if (defaultCoursier && fs.statSync(defaultCoursier).isFile()) {
+ if (
+ defaultCoursier &&
+ fs.existsSync(defaultCoursier) &&
+ fs.statSync(defaultCoursier).isFile()
+ ) {
  return validate(defaultCoursier);
  } else {
  return undefined;

packages/metals-vscode/src/extension.ts

@@ -193,7 +193,7 @@ async function fetchAndLaunchMetals(
  const metalsDirPath = metalsDir(ConfigurationTarget.Global);
 
  if (!fs.existsSync(metalsDirPath)) {
- fs.existsSync(metalsDirPath);
+ fs.mkdirSync(metalsDirPath);
  }
 
  const { coursier, javaHome } = await metalsLanguageClient.setupCoursier(