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Merged
datho7561 merged 1 commit into from
Sep 29, 2026
Merged

perf: optimize Java Language Server startup time #4514

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10 changes: 8 additions & 2 deletions src/extension.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -224,7 +224,7 @@ export async function activate(context: ExtensionContext): Promise<ExtensionAPI>
const requireStandardServer = (serverMode !== ServerMode.lightWeight) && (!isDebugModeByClientPort || !!process.env['JDTLS_CLIENT_PORT']);
let initFailureReported: boolean = false;

const javaConfig = await getJavaConfig(requirementsData.java_home);
const javaConfig = await getJavaConfig(requirementsData.java_home, true);
javaConfigDeferred.resolve(javaConfig);

// Options to control the language client
Expand Down Expand Up @@ -790,6 +790,12 @@ async function doStartStandardServer(context: ExtensionContext, requirements: re
await standardClient.initialize(context, requirements, clientOptions, workspacePath, jdtEventEmitter);
standardClient.start().then(async () => {
standardClient.registerLanguageClientActions(context, await fse.pathExists(path.join(workspacePath, ".metadata", ".plugins")), jdtEventEmitter);
// Send auto-detected JDKs after server startup to avoid blocking initialization
standardClient.getClient().sendNotification(DidChangeConfigurationNotification.type, {
settings: {
java: await getJavaConfig(requirements.java_home),
}
});
});
serverStatusBarProvider.setBusy("Activating...");
return standardClient.getClient();
Expand Down Expand Up @@ -1269,7 +1275,7 @@ async function cleanJavaWorkspaceStorage() {
}

async function cleanOldGlobalStorage(context: ExtensionContext) {
const currentVersion = getVersion(context.extensionPath);
const currentVersion = getVersion(context);
const globalStoragePath = context.globalStorageUri?.fsPath; // .../Code/User/globalStorage/redhat.java

ensureExists(globalStoragePath);
Expand Down
4 changes: 2 additions & 2 deletions src/javaServerStarter.ts
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Expand Up @@ -297,7 +297,7 @@ function prepareParams(requirements: RequirementsData, workspacePath, context: E
}

const hasJDWP = params.find((param: string) => param.includes('jdwp')) !== undefined;
const extVersion = getVersion(context.extensionPath);
const extVersion = getVersion(context);
const globalStoragePath = path.resolve(context.globalStorageUri?.fsPath, extVersion); // .../Code/User/globalStorage/redhat.java/1.42.0/
const appCDSMode = workspace.getConfiguration().get('java.jdt.ls.appcds.enabled');
const useAppCDS = (appCDSMode === 'on') || (appCDSMode === 'auto' && (isPrereleaseOrInsiderVersion(context)));
Expand Down Expand Up @@ -396,7 +396,7 @@ export function getSharedIndexCache(context: ExtensionContext): string {

function resolveConfiguration(context, configDir) {
ensureExists(context.globalStoragePath);
const version = getVersion(context.extensionPath);
const version = getVersion(context);
let configuration = path.resolve(context.globalStoragePath, version);
ensureExists(configuration);
configuration = path.resolve(configuration, configDir);
Expand Down
5 changes: 2 additions & 3 deletions src/jdkUtils.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -3,7 +3,7 @@
import { existsSync } from 'fs';
import { IJavaRuntime, findRuntimes, getSources } from 'jdk-utils';
import { join } from 'path';
import { ExtensionContext, Uri, workspace } from 'vscode';
import { ExtensionContext } from 'vscode';

let cachedJdks: IJavaRuntime[];
let cachedJreNames: string[];
Expand All @@ -14,8 +14,7 @@ export async function loadSupportedJreNames(context: ExtensionContext): Promise<
}

async function getContributesConfiguration(context: ExtensionContext, configId: string): Promise<any> {
const buffer = await workspace.fs.readFile(Uri.file(context.asAbsolutePath("package.json")));
const packageJson = JSON.parse(buffer.toString());
const packageJson = context.extension.packageJSON;
/**
* contributes.configuration can either be a single object,
* representing a single category of settings, or an array
Expand Down
14 changes: 5 additions & 9 deletions src/requirements.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@

import expandHomeDir from 'expand-home-dir';
import * as fse from 'fs-extra';
import { getRuntime, getSources, JAVAC_FILENAME, JAVA_FILENAME } from 'jdk-utils';
import { getRuntime, JAVAC_FILENAME, JAVA_FILENAME } from 'jdk-utils';
import * as path from 'path';
import { env, ExtensionContext, Uri, window, workspace } from 'vscode';
import { Commands } from './commands';
Expand Down Expand Up @@ -75,10 +75,10 @@ export async function resolveRequirements(context: ExtensionContext): Promise<Re
}
}

// search valid JDKs from env.JAVA_HOME, env.PATH, SDKMAN, jEnv, jabba, Common directories
const javaRuntimes = await listJdks();
if (!toolingJre) { // universal version
// search valid JDKs from env.JAVA_HOME, env.PATH, SDKMAN, jEnv, jabba, Common directories
// as latest version as possible.
const javaRuntimes = await listJdks();
sortJdksByVersion(javaRuntimes);
const validJdks = javaRuntimes.filter(r => r.version.major >= REQUIRED_JDK_VERSION);
if (validJdks.length > 0) {
Expand All @@ -100,16 +100,12 @@ export async function resolveRequirements(context: ExtensionContext): Promise<Re
*/
if (javaHome) {
logger.info(`Use the JDK from '${preferenceName}' setting as the initial default project JDK.`);
} else if (javaRuntimes.length) {
sortJdksBySource(javaRuntimes);
javaHome = javaRuntimes[0].homedir;
javaVersion = javaRuntimes[0].version?.major;
logger.info(`Use the JDK from '${getSources(javaRuntimes[0])}' as the initial default project JDK.`);
} else if (javaHome = await findDefaultRuntimeFromSettings()) {
javaVersion = await getMajorVersion(javaHome);
logger.info("Use the JDK from 'java.configuration.runtimes' as the initial default project JDK.");
} else {
openJDKDownload(reject, "Please download and install a JDK to compile your project. You can configure your projects with different JDKs by the setting ['java.configuration.runtimes'](https://github.com/redhat-developer/vscode-java/wiki/JDK-Requirements#java.configuration.runtimes)");
javaHome = toolingJre;
javaVersion = toolingJreVersion;
}
}

Expand Down
23 changes: 8 additions & 15 deletions src/utils.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -220,7 +220,7 @@ function getDirectoriesByBuildFile(inclusions: string[], exclusions: string[], f

const detectJdksAtStart: boolean = getJavaConfiguration().get<boolean>('configuration.detectJdksAtStart');

export async function getJavaConfig(javaHome: string) {
export async function getJavaConfig(javaHome: string, skipAutoDetection?: boolean) {
const origConfig = getJavaConfiguration();
const javaConfig = JSON.parse(JSON.stringify(origConfig));
javaConfig.home = javaHome;
Expand Down Expand Up @@ -274,7 +274,7 @@ export async function getJavaConfig(javaHome: string) {
}

javaConfig.telemetry = { enabled: workspace.getConfiguration('redhat.telemetry').get('enabled', false) };
if (detectJdksAtStart) {
if (detectJdksAtStart && !skipAutoDetection) {
const userConfiguredJREs: any[] = javaConfig.configuration.runtimes;
javaConfig.configuration.runtimes = await addAutoDetectedJdks(userConfiguredJREs);
}
Expand Down Expand Up @@ -344,14 +344,8 @@ export function resolveActualCause(callstack: any): any {
return callstack;
}

export function getVersion(extensionPath: string): string {
const packagePath = path.resolve(extensionPath, "package.json");
const packageFile = JSON.parse(fs.readFileSync(packagePath, 'utf8'));
if (packageFile) {
return packageFile.version;
}

return '0.0.0';
export function getVersion(context: ExtensionContext): string {
return context.extension.packageJSON?.version || '0.0.0';
}

export function getVSCodeVariablesMap(): any {
Expand All @@ -368,19 +362,18 @@ export function getVSCodeVariablesMap(): any {
* @param context The extension context or extension path
* @returns true if the version is a pre-release version or running an insider editor
*/
export function isPrereleaseOrInsiderVersion(context: ExtensionContext | string): boolean {
export function isPrereleaseOrInsiderVersion(context: ExtensionContext): boolean {
return isInsiderEditor() || isPreReleaseVersion(context);
}

/**
* Check if the extension version is a pre-release version.
* Pre-release versions follow the pattern: major.minor.timestamp (e.g., 1.47.1234567890)
* @param context The extension context or extension path
* @param context The extension context
* @returns true if the version is a pre-release version
*/
export function isPreReleaseVersion(context: ExtensionContext | string): boolean {
const extensionPath = typeof context === 'string' ? context : context.extensionPath;
const extVersion = getVersion(extensionPath);
export function isPreReleaseVersion(context: ExtensionContext): boolean {
const extVersion = getVersion(context);
return /^\d+\.\d+\.\d{10}/.test(extVersion);
}

Expand Down
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