Add nullability annotations

Signed-off-by: Simone Arpe <[email protected]>

Author: simoarpe

android/src/main/java/com/pspdfkit/flutter/pspdfkit/ConfigurationAdapter.java

@@ -29,6 +29,9 @@
 import java.util.EnumSet;
 import java.util.HashMap;
 
+import static com.pspdfkit.flutter.pspdfkit.util.Preconditions.requireNotNullNotEmpty;
+import static io.flutter.util.Preconditions.checkNotNull;
+
 class ConfigurationAdapter {
     private static final String LOG_TAG = "ConfigurationAdapter";
 
@@ -76,7 +79,7 @@ class ConfigurationAdapter {
     private static final String SETTINGS_MENU_ITEMS = "settingsMenuItems";
     private static final String SHOW_ACTION_NAVIGATION_BUTTONS = "showActionNavigationButtons";
 
-    private final PdfActivityConfiguration.Builder configuration;
+    @NonNull private final PdfActivityConfiguration.Builder configuration;
     @Nullable private String password = null;
 
     ConfigurationAdapter(@NonNull Context context,
@@ -187,7 +190,8 @@ private void configureShowPageNumberOverlay(boolean showPageNumberOverlay) {
         }
     }
 
-    private void configurePageScrollDirection(final String pageScrollDirection) {
+    private void configurePageScrollDirection(@NonNull final String pageScrollDirection) {
+        requireNotNullNotEmpty(pageScrollDirection, "pageScrollDirection");
         if (pageScrollDirection.equals(PAGE_SCROLL_DIRECTION_HORIZONTAL)) {
             configuration.scrollDirection(PageScrollDirection.HORIZONTAL);
         } else if (pageScrollDirection.equals(PAGE_SCROLL_DIRECTION_VERTICAL)) {
@@ -214,16 +218,25 @@ private void configureStartPage(int startPage) {
         configuration.page(startPage);
     }
 
-    private void configureUserInterfaceViewMode(String userInterfaceViewMode) {
-        UserInterfaceViewMode result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_AUTOMATIC;
-        if (userInterfaceViewMode.equals(USER_INTERFACE_VIEW_MODE_AUTOMATIC)) {
-            result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_AUTOMATIC;
-        } else if (userInterfaceViewMode.equals(USER_INTERFACE_VIEW_MODE_AUTOMATIC_BORDER_PAGES)) {
-            result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_AUTOMATIC_BORDER_PAGES;
-        } else if (userInterfaceViewMode.equals(USER_INTERFACE_VIEW_MODE_ALWAYS_VISIBLE)) {
-            result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_VISIBLE;
-        } else if (userInterfaceViewMode.equals(USER_INTERFACE_VIEW_MODE_ALWAYS_HIDDEN)) {
-            result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_HIDDEN;
+    private void configureUserInterfaceViewMode(@NonNull String userInterfaceViewMode) {
+        requireNotNullNotEmpty(userInterfaceViewMode, "userInterfaceViewMode");
+
+        UserInterfaceViewMode result;
+        switch (userInterfaceViewMode) {
+            case USER_INTERFACE_VIEW_MODE_AUTOMATIC:
+                result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_AUTOMATIC;
+                break;
+            case USER_INTERFACE_VIEW_MODE_AUTOMATIC_BORDER_PAGES:
+                result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_AUTOMATIC_BORDER_PAGES;
+                break;
+            case USER_INTERFACE_VIEW_MODE_ALWAYS_VISIBLE:
+                result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_VISIBLE;
+                break;
+            case USER_INTERFACE_VIEW_MODE_ALWAYS_HIDDEN:
+                result = UserInterfaceViewMode.USER_INTERFACE_VIEW_MODE_HIDDEN;
+                break;
+            default:
+                throw new IllegalArgumentException("Undefined user interface view mode for " + userInterfaceViewMode);
         }
         configuration.setUserInterfaceViewMode(result);
     }
@@ -240,7 +253,9 @@ private void configureImmersiveMode(boolean immersiveMode) {
         configuration.useImmersiveMode(immersiveMode);
     }
 
-    private void configureShowThumbnailBar(String showThumbnailBar) {
+    private void configureShowThumbnailBar(@NonNull String showThumbnailBar) {
+        requireNotNullNotEmpty(showThumbnailBar, "showThumbnailBar");
+
         ThumbnailBarMode thumbnailBarMode;
         switch (showThumbnailBar) {
             case SHOW_THUMBNAIL_BAR_FLOATING:
@@ -365,24 +380,34 @@ private void configureDocumentInfoView(boolean enableDocumentInfoView) {
         }
     }
 
-    private void configureThemeMode(String themeMode) {
-        ThemeMode result = ThemeMode.DEFAULT;
+    private void configureThemeMode(@NonNull String themeMode) {
+        requireNotNullNotEmpty(themeMode, "themeMode");
+
+        ThemeMode result;
         if (themeMode.equals(APPEARANCE_MODE_DEFAULT)) {
             result = ThemeMode.DEFAULT;
         } else if (themeMode.equals(APPEARANCE_MODE_NIGHT)) {
             result = ThemeMode.NIGHT;
+        } else {
+            throw new IllegalArgumentException("Undefined theme mode for " + themeMode);
         }
         configuration.themeMode(result);
     }
 
-    private void configureDarkThemeRes(String darkThemeResource, Context context) {
+    private void configureDarkThemeRes(@NonNull String darkThemeResource, @NonNull Context context) {
+        requireNotNullNotEmpty(darkThemeResource, "darkThemeResource");
+        checkNotNull(context);
+
         @StyleRes int darkThemeId = getStyleResourceId(darkThemeResource, context);
         if (darkThemeId != 0) {
             configuration.themeDark(darkThemeId);
         }
     }
 
-    private void configureDefaultThemeRes(String defaultThemeResource, Context context) {
+    private void configureDefaultThemeRes(@NonNull String defaultThemeResource, @NonNull Context context) {
+        requireNotNullNotEmpty(defaultThemeResource, "defaultThemeResource");
+        checkNotNull(context);
+
         @StyleRes int defaultThemeId = getStyleResourceId(defaultThemeResource, context);
         if (defaultThemeId != 0) {
             configuration.theme(defaultThemeId);
@@ -397,15 +422,20 @@ private void configureShowNavigationButtons(boolean showNavigationButtons) {
         }
     }
 
-    private static int getStyleResourceId(String styleName, Context context) {
+    private static int getStyleResourceId(@NonNull String styleName, @NonNull Context context) {
+        requireNotNullNotEmpty(styleName, "styleName");
+        checkNotNull(context);
+
         int resourceId = context.getResources().getIdentifier(styleName, "style", context.getPackageName());
         if (resourceId == 0) {
             Log.e(LOG_TAG, String.format("Style resource not found for %s", styleName));
         }
         return resourceId;
     }
 
-    private <T> void configureSettingsMenuItems(ArrayList<T> settingsMenuItems) {
+    private <T> void configureSettingsMenuItems(@NonNull ArrayList<T> settingsMenuItems) {
+        checkNotNull(settingsMenuItems);
+
         EnumSet<SettingsMenuItemType> settingsMenuItemTypes = EnumSet.noneOf(SettingsMenuItemType.class);
         for (T settingsMenuItem : settingsMenuItems) {
             if (!(settingsMenuItem instanceof String)) {
@@ -429,7 +459,9 @@ private <T> void configureSettingsMenuItems(ArrayList<T> settingsMenuItems) {
         configuration.setSettingsMenuItems(settingsMenuItemTypes);
     }
 
-    private <T> boolean containsKeyOfType(HashMap<String, Object> configurationMap, String key, Class<T> clazz) {
+    private <T> boolean containsKeyOfType(@NonNull HashMap<String, Object> configurationMap,
+                                          @NonNull String key,
+                                          @NonNull Class<T> clazz) {
         if (configurationMap.get(key) != null) {
             checkCast(configurationMap.get(key), clazz, key);
             return true;