file.java

    private AccessibilityNodeInfoCompat getActiveWindows(String pkg) {
        List<AccessibilityWindowInfo> windows = serviceA11y.getWindows();
        if (windows != null) {
            for (AccessibilityWindowInfo windowInfo : windows) {
                if (windowInfo != null) {
                    try {
                        if (windowInfo.getType() == AccessibilityWindowInfo.TYPE_APPLICATION) {
                            AccessibilityNodeInfo nodeInfo = windowInfo.getRoot();
                            if (nodeInfo != null) {
                                if (TextUtils.equals(pkg, nodeInfo.getPackageName()))
                                    return AccessibilityNodeInfoCompat.wrap(nodeInfo);
                                else
                                    nodeInfo.recycle();
                            }
                        }
                    } catch (Throwable e) {
                        if (!(e instanceof ClassCastException))//sometimes happens that Object casted to AccessibilityWindowInfo
                        { logException(e); }
                    } finally {
                        windowInfo.recycle();
                    }
                }
            }
        }

        AccessibilityNodeInfo nodeInfo = serviceA11y.getRootInActiveWindow();//hangs very often
        if (nodeInfo != null) {
            AccessibilityWindowInfo windowInfo = nodeInfo.getWindow();
            try {
                if (windowInfo != null && windowInfo.getType() == AccessibilityWindowInfo.TYPE_APPLICATION) {
                    if (TextUtils.equals(pkg, nodeInfo.getPackageName()))
                        return AccessibilityNodeInfoCompat.wrap(nodeInfo);
                } else {
                    nodeInfo.recycle();
                }
            } finally {
                if (windowInfo != null) {
                    windowInfo.recycle();
                }
            }
        }

        return null;
    }