Implement `IntoJava` for `Vec<T>`

2 files changed, 33 insertions, 1 deletions

diff --git a/mullvad-jni/src/into_java.rs b/mullvad-jni/src/into_java.rs
index 4f8fc3f287..471ff22c3d 100644
--- a/mullvad-jni/src/into_java.rs
+++ b/mullvad-jni/src/into_java.rs
@@ -1,6 +1,7 @@
 use crate::get_class;
 use jni::{
-    objects::{JObject, JString, JValue},
+    objects::{JList, JObject, JString, JValue},
+    sys::jint,
     JNIEnv,
 };
 use mullvad_types::{account::AccountData, settings::Settings};
@@ -34,6 +35,36 @@ impl<'env> IntoJava<'env> for String {
     }
 }
 
+impl<'env, T> IntoJava<'env> for Vec<T>
+where
+    T: IntoJava<'env>,
+    JObject<'env>: From<T::JavaType>,
+{
+    type JavaType = JObject<'env>;
+
+    fn into_java(self, env: &JNIEnv<'env>) -> Self::JavaType {
+        let class = get_class("java/util/ArrayList");
+        let initial_capacity = self.len();
+        let parameters = [JValue::Int(initial_capacity as jint)];
+
+        let list_object = env
+            .new_object(&class, "(I)V", &parameters)
+            .expect("Failed to create ArrayList object");
+
+        let list =
+            JList::from_env(env, list_object).expect("Failed to create JList from ArrayList");
+
+        for element in self {
+            let java_element = env.auto_local(JObject::from(element.into_java(env)));
+
+            list.add(java_element.as_obj())
+                .expect("Failed to add element to ArrayList");
+        }
+
+        list_object
+    }
+}
+
 impl<'env> IntoJava<'env> for AccountData {
     type JavaType = JObject<'env>;
 
diff --git a/mullvad-jni/src/lib.rs b/mullvad-jni/src/lib.rs
index 6195b56b52..61a0d602bf 100644
--- a/mullvad-jni/src/lib.rs
+++ b/mullvad-jni/src/lib.rs
@@ -19,6 +19,7 @@ use talpid_types::{tunnel::TunnelStateTransition, ErrorExt};
 const LOG_FILENAME: &str = "daemon.log";
 
 const CLASSES_TO_LOAD: &[&str] = &[
+    "java/util/ArrayList",
     "net/mullvad/mullvadvpn/model/AccountData",
     "net/mullvad/mullvadvpn/model/Settings",
 ];