diff --git a/src/ffi/java/buffer.rs b/src/ffi/java/buffer.rs
index 93225f5..4b6cbc2 100644
--- a/src/ffi/java/buffer.rs
+++ b/src/ffi/java/buffer.rs
@@ -147,8 +147,8 @@ pub extern "system" fn Java_mp_code_BufferController_send<'local>(
 	self_ptr: jlong,
 	input: JObject<'local>,
 ) {
-	let Ok(start) = env.get_field(&input, "start", "I")
-		.and_then(|sr| sr.i())
+	let Ok(start) = env.get_field(&input, "start", "J")
+		.and_then(|sr| sr.j())
 		.jexcept(&mut env)
 		.try_into()
 	else {
@@ -157,8 +157,8 @@ pub extern "system" fn Java_mp_code_BufferController_send<'local>(
 		return;
 	};
 	
-	let Ok(end) = env.get_field(&input, "end", "I")
-		.and_then(|er| er.i())
+	let Ok(end) = env.get_field(&input, "end", "J")
+		.and_then(|er| er.j())
 		.jexcept(&mut env)
 		.try_into()
 	else {
@@ -175,7 +175,7 @@ pub extern "system" fn Java_mp_code_BufferController_send<'local>(
 		.map(|b| b.into())
 		.jexcept(&mut env);
 
-	let hash = env.get_field(&input, "hash", "Ljava/util/OptionalLong")
+	let hash = env.get_field(&input, "hash", "Ljava/util/OptionalLong;")
 		.and_then(|hash| hash.l())
 		.and_then(|hash| {
 			if env.call_method(&hash, "isPresent", "()Z", &[]).and_then(|r| r.z()).jexcept(&mut env) {
diff --git a/src/ffi/java/mod.rs b/src/ffi/java/mod.rs
index 50379bb..16bb9fa 100644
--- a/src/ffi/java/mod.rs
+++ b/src/ffi/java/mod.rs
@@ -110,8 +110,12 @@ impl<T> JExceptable<T> for Result<T, jni::errors::Error> where T: Default {
 	fn jexcept(self, env: &mut jni::JNIEnv) -> T {
 		if let Err(err) = &self {
 			let msg = format!("{err}");
-			env.throw_new("mp/code/exceptions/JNIException", msg)
-				.expect("A severe error occurred: we were unable to create a JNIException. This is an unrecoverable state.");
+			if let Err(err) = env.throw_new("mp/code/exceptions/JNIException", msg) {
+				if let Err(err) = env.exception_describe() {
+					tracing::error!("An exception occurred and we failed to even describe it: {err:#?}.");
+				}
+				panic!("A severe error occurred: we were unable to create a JNIException from {err:#?}. This is an unrecoverable state.");
+			}
 		}
 		self.unwrap_or_default()
 	}
@@ -121,8 +125,12 @@ impl<T> JExceptable<T> for Result<T, uuid::Error> where T: Default {
 	fn jexcept(self, env: &mut jni::JNIEnv) -> T {
 		if let Err(err) = &self {
 			let msg = format!("{err}");
-			env.throw_new("java/lang/IllegalArgumentException", msg) 
-				.expect("A severe error occurred: we were unable to create a JNIException. This is an unrecoverable state.");
+			if let Err(err) = env.throw_new("java/lang/IllegalArgumentException", msg) {
+				if let Err(err) = env.exception_describe() {
+					tracing::error!("An exception occurred and we failed to even describe it: {err:#?}.");
+				}
+				panic!("A severe error occurred: we were unable to create a JNIException from {err:#?}. This is an unrecoverable state.");
+			}
 		}
 		self.unwrap_or_default()
 	}
diff --git a/src/ffi/java/workspace.rs b/src/ffi/java/workspace.rs
index 504a4fa..9298e08 100644
--- a/src/ffi/java/workspace.rs
+++ b/src/ffi/java/workspace.rs
@@ -33,6 +33,10 @@ pub extern "system" fn Java_mp_code_Workspace_get_1buffer<'local>(
 	self_ptr: jlong,
 	input: JString<'local>
 ) -> jobject {
+	if input.is_null() {
+		return std::ptr::null_mut();
+	}
+
 	let workspace = unsafe { Box::leak(Box::from_raw(self_ptr as *mut Workspace)) };
 	let path = unsafe { env.get_string_unchecked(&input) }
 		.map(|path| path.to_string_lossy().to_string())