void activate()

in src/main/java/org/apache/sling/scripting/sightly/impl/engine/compiled/SlingHTLMasterCompiler.java [122:172]
47 lines of code
8 McCabe index (conditional complexity)

    void activate() {
        LOGGER.info("Activating {}", getClass().getName());

        String version = System.getProperty("java.specification.version");
        options = new Options();
        options.put(Options.KEY_GENERATE_DEBUG_INFO, true);
        options.put(Options.KEY_SOURCE_VERSION, version);
        options.put(Options.KEY_TARGET_VERSION, version);
        options.put(Options.KEY_CLASS_LOADER_WRITER, classLoaderWriter);
        options.put(Options.KEY_FORCE_COMPILATION, true);

        InputStream is;
        boolean newVersion = true;
        String versionInfo = null;
        String newVersionString = sightlyEngineConfiguration.getEngineVersion();
        try {
            is = classLoaderWriter.getInputStream(SIGHTLY_CONFIG_FILE);
            if (is != null) {
                versionInfo = IOUtils.toString(is, StandardCharsets.UTF_8);
                if (newVersionString.equals(versionInfo)) {
                    newVersion = false;
                } else {
                    LOGGER.info(
                            "Detected stale classes generated by Apache Sling Scripting HTL engine version {}.",
                            versionInfo);
                }
                IOUtils.closeQuietly(is);
            }
        } catch (IOException e) {
            // do nothing; if we didn't find any previous version information we're considering our version to be new
        }
        if (newVersion) {
            OutputStream os = classLoaderWriter.getOutputStream(SIGHTLY_CONFIG_FILE);
            try {
                IOUtils.write(sightlyEngineConfiguration.getEngineVersion(), os, StandardCharsets.UTF_8);
            } catch (IOException e) {
                // ignore
            } finally {
                IOUtils.closeQuietly(os);
            }
            String scratchFolder = sightlyEngineConfiguration.getScratchFolder();
            boolean scratchFolderDeleted = classLoaderWriter.delete(scratchFolder);
            if (scratchFolderDeleted && StringUtils.isNotEmpty(versionInfo)) {
                LOGGER.info(
                        "Deleted stale classes generated by Apache Sling Scripting HTL engine version {}.",
                        versionInfo);
            }
        }
        sightlyCompiler =
                SightlyCompiler.withKnownExpressionOptions(sightlyEngineConfiguration.getAllowedExpressionOptions());
    }