feat(setup-check): add JavaSetupCheck

Adds JavaSetupCheck to verify Java installation, path, version and encoding.

Related issue: #6590
Type: Feature

Checklist:
- [x] Implement ISetupCheck interface
- [x] Use SetupCheckUtils trait
- [x] Verify Java path exists
- [x] Check Java version matches required version
- [x] Check native.encoding for UTF-8
- [x] Return SetupResult with appropriate severity and translated messages
- [x] Add unit tests covering all scenarios

Author: guilhermercarvalho

lib/SetupCheck/JavaSetupCheck.php

@@ -0,0 +1,154 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2026 LibreCode coop and contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Libresign\SetupCheck;
+
+use OCA\Libresign\Helper\JavaHelper;
+use OCA\Libresign\Service\Install\SignSetupService;
+use OCA\Libresign\Service\Install\InstallService;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\App\IAppManager;
+use OCP\SetupCheck\ISetupCheck;
+use OCP\SetupCheck\SetupResult;
+use OCP\IConfig;
+use Psr\Log\LoggerInterface;
+
+class JavaSetupCheck implements ISetupCheck
+{
+  use SetupCheckUtils;
+
+  private IL10N $l10n;
+  private JavaHelper $javaHelper;
+  private IConfig $systemConfig;
+
+  private SignSetupService $signSetupService;
+  private IURLGenerator $urlGenerator;
+  private IAppManager $appManager;
+  private LoggerInterface $logger;
+
+  public function __construct(
+    IL10N $l10n,
+    JavaHelper $javaHelper,
+    SignSetupService $signSetupService,
+    IURLGenerator $urlGenerator,
+    IAppManager $appManager,
+    LoggerInterface $logger,
+    IConfig $systemConfig
+  ) {
+    $this->l10n = $l10n;
+    $this->javaHelper = $javaHelper;
+    $this->signSetupService = $signSetupService;
+    $this->urlGenerator = $urlGenerator;
+    $this->appManager = $appManager;
+    $this->logger = $logger;
+    $this->systemConfig = $systemConfig;
+  }
+
+  public function getName(): string
+  {
+    return $this->l10n->t('Java');
+  }
+
+  public function getCategory(): string
+  {
+    return 'system';
+  }
+
+  public function run(): SetupResult
+  {
+    $debugEnabled = $this->systemConfig->getSystemValueBool('debug', false);
+    $javaPath = $this->javaHelper->getJavaPath();
+
+    if (!$javaPath) {
+      return SetupResult::error(
+        $this->l10n->t('Java not installed'),
+        $this->l10n->t('Run occ libresign:install --java')
+      );
+    }
+
+    $verifyResult = $this->verifyResourceIntegrity('java', $debugEnabled);
+    if (!empty($verifyResult)) {
+      [$errorMsg, $tip] = $this->getErrorAndTipFromVerify($verifyResult, 'java', $debugEnabled, $this->l10n);
+      return SetupResult::error($errorMsg, $tip);
+    }
+
+    if (!file_exists($javaPath)) {
+      return SetupResult::error(
+        $this->l10n->t('Java binary not found: %s', [$javaPath]),
+        $this->l10n->t('Run occ libresign:install --java')
+      );
+    }
+
+    exec($javaPath . ' -version 2>&1', $output, $returnCode);
+    if (empty($output)) {
+      return SetupResult::error(
+        $this->l10n->t('Failed to execute Java. Sounds that your operational system is blocking the JVM.'),
+        'https://github.com/LibreSign/libresign/issues/2327#issuecomment-1961988790'
+      );
+    }
+    if ($returnCode !== 0) {
+      return SetupResult::error(
+        $this->l10n->t('Failure to check Java version.'),
+        $this->l10n->t('Run occ libresign:install --java')
+      );
+    }
+
+    $javaVersion = trim($output[0] ?? '');
+    if ($javaVersion !== InstallService::JAVA_VERSION) {
+      return SetupResult::error(
+        $this->l10n->t('Invalid java version. Found: %s expected: %s', [$javaVersion, InstallService::JAVA_VERSION]),
+        $this->l10n->t('Run occ libresign:install --java')
+      );
+    }
+
+    exec($javaPath . ' -XshowSettings:properties -version 2>&1', $encodingOutput);
+    $fullOutput = implode("\n", $encodingOutput);
+    preg_match('/native.encoding = (?<encoding>.*?)(\n|$)/', $fullOutput, $matches);
+    $encoding = $matches['encoding'] ?? null;
+
+    if (!$encoding) {
+      return SetupResult::error(
+        $this->l10n->t('Java encoding not found.'),
+        sprintf('The command %s need to have native.encoding', $javaPath . ' -XshowSettings:properties -version')
+      );
+    }
+
+    if (!str_contains($encoding, 'UTF-8')) {
+      $detectedEncoding = trim($encoding);
+      $phpLocale = setlocale(LC_CTYPE, 0) ?: 'not set';
+      $phpLcAll = getenv('LC_ALL') ?: 'not set';
+      $phpLang = getenv('LANG') ?: 'not set';
+
+      $tip = sprintf(
+        "Java detected encoding \"%s\" but UTF-8 is required.\n\n"
+          . "**Current PHP environment:**\n"
+          . "- LC_CTYPE: %s\n"
+          . "- LC_ALL: %s\n"
+          . "- LANG: %s\n\n"
+          . "**To fix this issue:**\n"
+          . "1. Set LC_ALL and LANG environment variables (e.g., LC_ALL=en_US.UTF-8) for your web server user\n"
+          . "2. Restart your web server after making changes\n"
+          . "3. Verify with command: `locale charmap` (should return UTF-8)\n\n"
+          . 'For more details, see: [Issue #4872](https://github.com/LibreSign/libresign/issues/4872)',
+        $detectedEncoding,
+        $phpLocale,
+        $phpLcAll,
+        $phpLang
+      );
+      return SetupResult::info(
+        $this->l10n->t('Non-UTF-8 encoding detected: %s. This may cause issues with accented or special characters', [$detectedEncoding]),
+        $tip
+      );
+    }
+
+    $message = $this->l10n->t('Java version: %s', [$javaVersion]) . "\n" .
+      $this->l10n->t('Java binary: %s', [$javaPath]);
+    return SetupResult::success($message);
+  }
+}