Add missing nullability annotations to Remote Config. (#608)

Author: vkryachko

firebase-config/firebase-config.gradle

@@ -22,7 +22,6 @@ plugins {
 firebaseLibrary {
     testLab.enabled = true
     publishSources = true
-    staticAnalysis.disableKotlinInteropLint()
 }
 
 protobuf {

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfig.java

@@ -72,12 +72,14 @@ public class FirebaseRemoteConfig {
    * @return A singleton instance of {@link FirebaseRemoteConfig} for the default {@link
    *     FirebaseApp}.
    */
+  @NonNull
   public static FirebaseRemoteConfig getInstance() {
     return getInstance(FirebaseApp.getInstance());
   }
 
   /** Returns an instance of Firebase Remote Config for the given {@link FirebaseApp}. */
-  public static FirebaseRemoteConfig getInstance(FirebaseApp app) {
+  @NonNull
+  public static FirebaseRemoteConfig getInstance(@NonNull FirebaseApp app) {
     return app.get(RemoteConfigComponent.class).getDefault();
   }
 
@@ -178,6 +180,7 @@ public static FirebaseRemoteConfig getInstance(FirebaseApp app) {
    * Returns a {@link Task} representing the initialization status of this Firebase Remote Config
    * instance.
    */
+  @NonNull
   public Task<FirebaseRemoteConfigInfo> ensureInitialized() {
     Task<ConfigContainer> activatedConfigsTask = activatedConfigsCache.get();
     Task<ConfigContainer> defaultsConfigsTask = defaultConfigsCache.get();
@@ -202,6 +205,7 @@ public Task<FirebaseRemoteConfigInfo> ensureInitialized() {
    *     configs; if no configs were fetched from the backend and the local fetched configs have
    *     already been activated, returns a {@link Task} with a {@code false} result.
    */
+  @NonNull
   public Task<Boolean> fetchAndActivate() {
     return fetch().onSuccessTask(executor, (unusedVoid) -> activate());
   }
@@ -248,6 +252,7 @@ public boolean activateFetched() {
    *     configs; if the fetched configs were already activated by a previous call, returns a {@link
    *     Task} with a {@code false} result.
    */
+  @NonNull
   public Task<Boolean> activate() {
     Task<ConfigContainer> fetchedConfigsTask = fetchedConfigsCache.get();
     Task<ConfigContainer> activatedConfigsTask = activatedConfigsCache.get();
@@ -293,6 +298,7 @@ public Task<Boolean> activate() {
    *
    * @return {@link Task} representing the {@code fetch} call.
    */
+  @NonNull
   public Task<Void> fetch() {
     Task<FetchResponse> fetchTask = fetchHandler.fetch();
 
@@ -317,6 +323,7 @@ public Task<Void> fetch() {
    *     this many seconds ago, configs are served from the backend instead of local storage.
    * @return {@link Task} representing the {@code fetch} call.
    */
+  @NonNull
   public Task<Void> fetch(long minimumFetchIntervalInSeconds) {
     Task<FetchResponse> fetchTask = fetchHandler.fetch(minimumFetchIntervalInSeconds);
 
@@ -339,7 +346,8 @@ public Task<Void> fetch(long minimumFetchIntervalInSeconds) {
    * @return {@link String} representing the value of the Firebase Remote Config parameter with the
    *     given key.
    */
-  public String getString(String key) {
+  @NonNull
+  public String getString(@NonNull String key) {
     return getHandler.getString(key);
   }
 
@@ -364,7 +372,7 @@ public String getString(String key) {
    * @return {@code boolean} representing the value of the Firebase Remote Config parameter with the
    *     given key.
    */
-  public boolean getBoolean(String key) {
+  public boolean getBoolean(@NonNull String key) {
     return getHandler.getBoolean(key);
   }
 
@@ -383,8 +391,9 @@ public boolean getBoolean(String key) {
    * @return {@code byte[]} representing the value of the Firebase Remote Config parameter with the
    *     given key.
    */
+  @NonNull
   @Deprecated
-  public byte[] getByteArray(String key) {
+  public byte[] getByteArray(@NonNull String key) {
     return getHandler.getByteArray(key);
   }
 
@@ -405,7 +414,7 @@ public byte[] getByteArray(String key) {
    * @return {@code double} representing the value of the Firebase Remote Config parameter with the
    *     given key.
    */
-  public double getDouble(String key) {
+  public double getDouble(@NonNull String key) {
     return getHandler.getDouble(key);
   }
 
@@ -426,7 +435,7 @@ public double getDouble(String key) {
    * @return {@code long} representing the value of the Firebase Remote Config parameter with the
    *     given key.
    */
-  public long getLong(String key) {
+  public long getLong(@NonNull String key) {
     return getHandler.getLong(key);
   }
 
@@ -445,7 +454,8 @@ public long getLong(String key) {
    * @return {@link FirebaseRemoteConfigValue} representing the value of the Firebase Remote Config
    *     parameter with the given key.
    */
-  public FirebaseRemoteConfigValue getValue(String key) {
+  @NonNull
+  public FirebaseRemoteConfigValue getValue(@NonNull String key) {
     return getHandler.getValue(key);
   }
 
@@ -455,7 +465,8 @@ public FirebaseRemoteConfigValue getValue(String key) {
    * @param prefix The key prefix to look for. If the prefix is empty, all keys are returned.
    * @return {@link Set} of Remote Config parameter keys that start with the specified prefix.
    */
-  public Set<String> getKeysByPrefix(String prefix) {
+  @NonNull
+  public Set<String> getKeysByPrefix(@NonNull String prefix) {
     return getHandler.getKeysByPrefix(prefix);
   }
 
@@ -469,6 +480,7 @@ public Set<String> getKeysByPrefix(String prefix) {
    *   <li>The default value, if the key was set with {@link #setDefaultsAsync}.
    * </ol>
    */
+  @NonNull
   public Map<String, FirebaseRemoteConfigValue> getAll() {
     return getHandler.getAll();
   }
@@ -477,6 +489,7 @@ public Map<String, FirebaseRemoteConfigValue> getAll() {
    * Returns the state of this {@link FirebaseRemoteConfig} instance as a {@link
    * FirebaseRemoteConfigInfo}.
    */
+  @NonNull
   public FirebaseRemoteConfigInfo getInfo() {
     return frcMetadata.getInfo();
   }
@@ -488,7 +501,7 @@ public FirebaseRemoteConfigInfo getInfo() {
    * @deprecated Use {@link #setConfigSettingsAsync(FirebaseRemoteConfigSettings)} instead.
    */
   @Deprecated
-  public void setConfigSettings(FirebaseRemoteConfigSettings settings) {
+  public void setConfigSettings(@NonNull FirebaseRemoteConfigSettings settings) {
     frcMetadata.setConfigSettingsWithoutWaitingOnDiskWrite(settings);
   }
 
@@ -497,7 +510,8 @@ public void setConfigSettings(FirebaseRemoteConfigSettings settings) {
    *
    * @param settings The new settings to be applied.
    */
-  public Task<Void> setConfigSettingsAsync(FirebaseRemoteConfigSettings settings) {
+  @NonNull
+  public Task<Void> setConfigSettingsAsync(@NonNull FirebaseRemoteConfigSettings settings) {
     return Tasks.call(
         executor,
         () -> {
@@ -526,7 +540,7 @@ public Task<Void> setConfigSettingsAsync(FirebaseRemoteConfigSettings settings)
    * @deprecated Use {@link #setDefaultsAsync} instead.
    */
   @Deprecated
-  public void setDefaults(Map<String, Object> defaults) {
+  public void setDefaults(@NonNull Map<String, Object> defaults) {
     // Fetch values from the server are in the Map<String, String> format, so match that here.
     Map<String, String> defaultsStringMap = new HashMap<>();
     for (Map.Entry<String, Object> defaultsEntry : defaults.entrySet()) {
@@ -552,7 +566,8 @@ public void setDefaults(Map<String, Object> defaults) {
    * @param defaults {@link Map} of key value pairs representing Firebase Remote Config parameter
    *     keys and values.
    */
-  public Task<Void> setDefaultsAsync(Map<String, Object> defaults) {
+  @NonNull
+  public Task<Void> setDefaultsAsync(@NonNull Map<String, Object> defaults) {
     // Fetch values from the server are in the Map<String, String> format, so match that here.
     Map<String, String> defaultsStringMap = new HashMap<>();
     for (Map.Entry<String, Object> defaultsEntry : defaults.entrySet()) {
@@ -579,6 +594,7 @@ public void setDefaults(@XmlRes int resourceId) {
    * @param resourceId Id for the XML resource, which should be in your application's {@code
    *     res/xml} folder.
    */
+  @NonNull
   public Task<Void> setDefaultsAsync(@XmlRes int resourceId) {
     Map<String, String> xmlDefaults = DefaultsXmlParser.getDefaultsFromXml(context, resourceId);
     return setDefaultsWithStringsMapAsync(xmlDefaults);
@@ -590,6 +606,7 @@ public Task<Void> setDefaultsAsync(@XmlRes int resourceId) {
    *
    * @return {@link Task} representing the {@code clear} call.
    */
+  @NonNull
   public Task<Void> reset() {
     // Use a Task to avoid throwing potential file I/O errors to the caller and because
     // frcMetadata's clear call is blocking.

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigClientException.java

@@ -14,6 +14,9 @@
 
 package com.google.firebase.remoteconfig;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
 /**
  * A Firebase Remote Config internal issue that isn't caused by an interaction with the Firebase
  * Remote Config server.
@@ -22,12 +25,13 @@
  */
 public class FirebaseRemoteConfigClientException extends FirebaseRemoteConfigException {
   /** Creates a Firebase Remote Config client exception with the given message. */
-  public FirebaseRemoteConfigClientException(String detailMessage) {
+  public FirebaseRemoteConfigClientException(@NonNull String detailMessage) {
     super(detailMessage);
   }
 
   /** Creates a Firebase Remote Config client exception with the given message and cause. */
-  public FirebaseRemoteConfigClientException(String detailMessage, Throwable cause) {
+  public FirebaseRemoteConfigClientException(
+      @NonNull String detailMessage, @Nullable Throwable cause) {
     super(detailMessage, cause);
   }
 }

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigException.java

@@ -14,17 +14,19 @@
 
 package com.google.firebase.remoteconfig;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import com.google.firebase.FirebaseException;
 
 /** Base class for {@link FirebaseRemoteConfig} exceptions. */
 public class FirebaseRemoteConfigException extends FirebaseException {
   /** Creates a Firebase Remote Config exception with the given message. */
-  public FirebaseRemoteConfigException(String detailMessage) {
+  public FirebaseRemoteConfigException(@NonNull String detailMessage) {
     super(detailMessage);
   }
 
   /** Creates a Firebase Remote Config exception with the given message and cause. */
-  public FirebaseRemoteConfigException(String detailMessage, Throwable cause) {
+  public FirebaseRemoteConfigException(@NonNull String detailMessage, @Nullable Throwable cause) {
     super(detailMessage, cause);
   }
 }

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigFetchException.java

@@ -14,6 +14,9 @@
 
 package com.google.firebase.remoteconfig;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
 /**
  * Exception thrown when the {@link FirebaseRemoteConfig#fetch()} operation cannot be completed
  * successfully.
@@ -24,12 +27,13 @@
 @Deprecated
 public class FirebaseRemoteConfigFetchException extends FirebaseRemoteConfigException {
   /** Creates a Firebase Remote Config fetch exception with the given message. */
-  public FirebaseRemoteConfigFetchException(String detailMessage) {
+  public FirebaseRemoteConfigFetchException(@NonNull String detailMessage) {
     super(detailMessage);
   }
 
   /** Creates a Firebase Remote Config fetch exception with the given message and cause. */
-  public FirebaseRemoteConfigFetchException(String detailMessage, Throwable cause) {
+  public FirebaseRemoteConfigFetchException(
+      @NonNull String detailMessage, @Nullable Throwable cause) {
     super(detailMessage, cause);
   }
 }

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigInfo.java

@@ -14,6 +14,8 @@
 
 package com.google.firebase.remoteconfig;
 
+import androidx.annotation.NonNull;
+
 /** Wraps the current state of the FirebaseRemoteConfig singleton object. */
 public interface FirebaseRemoteConfigInfo {
   /**
@@ -23,7 +25,7 @@ public interface FirebaseRemoteConfigInfo {
    * @return -1 if no fetch attempt has been made yet. Otherwise, returns the timestamp of the last
    *     successful fetch operation.
    */
-  public long getFetchTimeMillis();
+  long getFetchTimeMillis();
 
   /**
    * Gets the status of the most recent fetch attempt.
@@ -33,12 +35,13 @@ public interface FirebaseRemoteConfigInfo {
    *     FirebaseRemoteConfig#LAST_FETCH_STATUS_THROTTLED}, or {@link
    *     FirebaseRemoteConfig#LAST_FETCH_STATUS_NO_FETCH_YET}.
    */
-  public int getLastFetchStatus();
+  int getLastFetchStatus();
 
   /**
    * Gets the current settings of the FirebaseRemoteConfig singleton object.
    *
    * @return A {@link FirebaseRemoteConfigSettings} object indicating the current settings.
    */
-  public FirebaseRemoteConfigSettings getConfigSettings();
+  @NonNull
+  FirebaseRemoteConfigSettings getConfigSettings();
 }

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigServerException.java

@@ -14,6 +14,9 @@
 
 package com.google.firebase.remoteconfig;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
 /**
  * A Firebase Remote Config internal issue caused by an interaction with the Firebase Remote Config
  * server.
@@ -26,7 +29,7 @@ public class FirebaseRemoteConfigServerException extends FirebaseRemoteConfigExc
   /**
    * Creates a Firebase Remote Config server exception with the given message and HTTP status code.
    */
-  public FirebaseRemoteConfigServerException(int httpStatusCode, String detailMessage) {
+  public FirebaseRemoteConfigServerException(int httpStatusCode, @NonNull String detailMessage) {
     super(detailMessage);
     this.httpStatusCode = httpStatusCode;
   }
@@ -35,7 +38,7 @@ public FirebaseRemoteConfigServerException(int httpStatusCode, String detailMess
    * Creates a Firebase Remote Config server exception with the given message, HTTP status code and
    */
   public FirebaseRemoteConfigServerException(
-      int httpStatusCode, String detailMessage, Throwable cause) {
+      int httpStatusCode, @NonNull String detailMessage, @Nullable Throwable cause) {
     super(detailMessage, cause);
     this.httpStatusCode = httpStatusCode;
   }

firebase-config/src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigSettings.java

@@ -17,6 +17,8 @@
 import static com.google.firebase.remoteconfig.RemoteConfigComponent.NETWORK_CONNECTION_TIMEOUT_IN_SECONDS;
 import static com.google.firebase.remoteconfig.internal.ConfigFetchHandler.DEFAULT_MINIMUM_FETCH_INTERVAL_IN_SECONDS;
 
+import androidx.annotation.NonNull;
+
 /**
  * Wraps the settings for {@link FirebaseRemoteConfig} operations.
  *
@@ -60,6 +62,7 @@ public long getMinimumFetchIntervalInSeconds() {
   }
 
   /** Constructs a builder initialized with the current FirebaseRemoteConfigSettings. */
+  @NonNull
   public FirebaseRemoteConfigSettings.Builder toBuilder() {
     FirebaseRemoteConfigSettings.Builder frcBuilder = new FirebaseRemoteConfigSettings.Builder();
     frcBuilder.setDeveloperModeEnabled(this.isDeveloperModeEnabled());
@@ -82,6 +85,7 @@ public static class Builder {
      *     setting.
      * @deprecated Use {@link #setMinimumFetchIntervalInSeconds(long)} instead.
      */
+    @NonNull
     @Deprecated
     public Builder setDeveloperModeEnabled(boolean enabled) {
       enableDeveloperMode = enabled;
@@ -97,6 +101,7 @@ public Builder setDeveloperModeEnabled(boolean enabled) {
      *
      * @param duration Timeout duration in seconds. Should be a non-negative number.
      */
+    @NonNull
     public Builder setFetchTimeoutInSeconds(long duration) throws IllegalArgumentException {
       if (duration < 0) {
         throw new IllegalArgumentException(
@@ -117,6 +122,7 @@ public Builder setFetchTimeoutInSeconds(long duration) throws IllegalArgumentExc
      *
      * @param duration Interval duration in seconds. Should be a non-negative number.
      */
+    @NonNull
     public Builder setMinimumFetchIntervalInSeconds(long duration) {
       if (duration < 0) {
         throw new IllegalArgumentException(
@@ -131,6 +137,7 @@ public Builder setMinimumFetchIntervalInSeconds(long duration) {
     /**
      * Returns a {@link FirebaseRemoteConfigSettings} with the settings provided to this builder.
      */
+    @NonNull
     public FirebaseRemoteConfigSettings build() {
       return new FirebaseRemoteConfigSettings(this);
     }