public List getActivateExtension()

in dubbo-common/src/main/java/org/apache/dubbo/common/extension/ExtensionLoader.java [343:438]
84 lines of code
27 McCabe index (conditional complexity)

    public List<T> getActivateExtension(URL url, String[] values, String group) {
        checkDestroyed();
        // solve the bug of using @SPI's wrapper method to report a null pointer exception.
        Map<Class<?>, T> activateExtensionsMap = new TreeMap<>(activateComparator);
        List<String> names = values == null
                ? new ArrayList<>(0)
                : Arrays.stream(values).map(StringUtils::trim).collect(Collectors.toList());
        Set<String> namesSet = new HashSet<>(names);
        if (!namesSet.contains(REMOVE_VALUE_PREFIX + DEFAULT_KEY)) {
            if (cachedActivateGroups.size() == 0) {
                synchronized (cachedActivateGroups) {
                    // cache all extensions
                    if (cachedActivateGroups.size() == 0) {
                        getExtensionClasses();
                        for (Map.Entry<String, Object> entry : cachedActivates.entrySet()) {
                            String name = entry.getKey();
                            Object activate = entry.getValue();

                            String[] activateGroup, activateValue;

                            if (activate instanceof Activate) {
                                activateGroup = ((Activate) activate).group();
                                activateValue = ((Activate) activate).value();
                            } else if (Dubbo2CompactUtils.isEnabled()
                                    && Dubbo2ActivateUtils.isActivateLoaded()
                                    && Dubbo2ActivateUtils.getActivateClass().isAssignableFrom(activate.getClass())) {
                                activateGroup = Dubbo2ActivateUtils.getGroup((Annotation) activate);
                                activateValue = Dubbo2ActivateUtils.getValue((Annotation) activate);
                            } else {
                                continue;
                            }
                            cachedActivateGroups.put(name, new HashSet<>(Arrays.asList(activateGroup)));
                            String[][] keyPairs = new String[activateValue.length][];
                            for (int i = 0; i < activateValue.length; i++) {
                                if (activateValue[i].contains(":")) {
                                    keyPairs[i] = new String[2];
                                    String[] arr = activateValue[i].split(":");
                                    keyPairs[i][0] = arr[0];
                                    keyPairs[i][1] = arr[1];
                                } else {
                                    keyPairs[i] = new String[1];
                                    keyPairs[i][0] = activateValue[i];
                                }
                            }
                            cachedActivateValues.put(name, keyPairs);
                        }
                    }
                }
            }

            // traverse all cached extensions
            cachedActivateGroups.forEach((name, activateGroup) -> {
                if (isMatchGroup(group, activateGroup)
                        && !namesSet.contains(name)
                        && !namesSet.contains(REMOVE_VALUE_PREFIX + name)
                        && isActive(cachedActivateValues.get(name), url)) {

                    activateExtensionsMap.put(getExtensionClass(name), getExtension(name));
                }
            });
        }

        if (namesSet.contains(DEFAULT_KEY)) {
            // will affect order
            // `ext1,default,ext2` means ext1 will happens before all of the default extensions while ext2 will after
            // them
            ArrayList<T> extensionsResult = new ArrayList<>(activateExtensionsMap.size() + names.size());
            for (String name : names) {
                if (name.startsWith(REMOVE_VALUE_PREFIX) || namesSet.contains(REMOVE_VALUE_PREFIX + name)) {
                    continue;
                }
                if (DEFAULT_KEY.equals(name)) {
                    extensionsResult.addAll(activateExtensionsMap.values());
                    continue;
                }
                if (containsExtension(name)) {
                    extensionsResult.add(getExtension(name));
                }
            }
            return extensionsResult;
        } else {
            // add extensions, will be sorted by its order
            for (String name : names) {
                if (name.startsWith(REMOVE_VALUE_PREFIX) || namesSet.contains(REMOVE_VALUE_PREFIX + name)) {
                    continue;
                }
                if (DEFAULT_KEY.equals(name)) {
                    continue;
                }
                if (containsExtension(name)) {
                    activateExtensionsMap.put(getExtensionClass(name), getExtension(name));
                }
            }
            return new ArrayList<>(activateExtensionsMap.values());
        }
    }