Bindings for injectable Java video encoders.

webrtc/sdk/android/src/jni/jni_helpers.cc

Index: webrtc/sdk/android/src/jni/jni_helpers.cc
diff --git a/webrtc/sdk/android/src/jni/jni_helpers.cc b/webrtc/sdk/android/src/jni/jni_helpers.cc
index f6b4b6f6e5a732b97b108bf41b341d9671506826..03847666dad9db5788756b728ed519b74c956712 100644
--- a/webrtc/sdk/android/src/jni/jni_helpers.cc
+++ b/webrtc/sdk/android/src/jni/jni_helpers.cc
@@ -307,6 +307,41 @@ std::string GetJavaEnumName(JNIEnv* jni,
   return JavaToStdString(jni, name);
 }
 
+std::map<std::string, std::string> JavaToStdMapStrings(JNIEnv* jni,
+                                                       jobject j_map) {
+  jclass map_class = jni->FindClass("java/util/Map");
+  jclass set_class = jni->FindClass("java/util/Set");
+  jclass iterator_class = jni->FindClass("java/util/Iterator");
+  jclass entry_class = jni->FindClass("java/util/Map$Entry");
+  jmethodID entry_set_method =
+      jni->GetMethodID(map_class, "entrySet", "()Ljava/util/Set;");
+  jmethodID iterator_method =
+      jni->GetMethodID(set_class, "iterator", "()Ljava/util/Iterator;");
+  jmethodID has_next_method =
+      jni->GetMethodID(iterator_class, "hasNext", "()Z");
+  jmethodID next_method =
+      jni->GetMethodID(iterator_class, "next", "()Ljava/lang/Object;");
+  jmethodID get_key_method =
+      jni->GetMethodID(entry_class, "getKey", "()Ljava/lang/Object;");
+  jmethodID get_value_method =
+      jni->GetMethodID(entry_class, "getValue", "()Ljava/lang/Object;");
+
+  jobject j_entry_set = jni->CallObjectMethod(j_map, entry_set_method);
+  jobject j_iterator = jni->CallObjectMethod(j_entry_set, iterator_method);
+
+  std::map<std::string, std::string> result;
+  while (jni->CallBooleanMethod(j_iterator, has_next_method)) {
+    jobject j_entry = jni->CallObjectMethod(j_iterator, next_method);
+    jstring j_key =
+        static_cast<jstring>(jni->CallObjectMethod(j_entry, get_key_method));
+    jstring j_value =
+        static_cast<jstring>(jni->CallObjectMethod(j_entry, get_value_method));
+    result[JavaToStdString(jni, j_key)] = JavaToStdString(jni, j_value);
+  }
+
+  return result;
+}
+
 jobject NewGlobalRef(JNIEnv* jni, jobject o) {
   jobject ret = jni->NewGlobalRef(o);
   CHECK_EXCEPTION(jni) << "error during NewGlobalRef";