feat: initial work on jni-rs java glue

.gitignore

@@ -12,3 +12,9 @@ node_modules/
 package-lock.json
 index.d.ts
 index.node
+
+# java
+java/*.iml
+java/.idea/
+java/*.h
+java/**/*.class

build.rs

@@ -6,93 +6,6 @@ extern crate pyo3_build_config;
 
 /// The main method of the buildscript, required by some glue modules.
 fn main() {
-	#[cfg(feature = "java")]
-	{
-		let pkg = "com.codemp.jni".to_string();
-		let pkg_folder = pkg.replace('.', "/"); // java moment
-
-		let out_dir = std::env::var("OUT_DIR").expect("cargo did not provide OUT_DIR");
-		let out_dir = std::path::Path::new(&out_dir);
-		let generated_glue_file = out_dir.join("generated_glue.in");
-		let src_dir = std::path::Path::new("src").join("ffi").join("java");
-		let typemap_file = src_dir.join("typemap.in");
-		rifgen::Generator::new(
-			rifgen::TypeCases::CamelCase,
-			rifgen::Language::Java,
-			vec![src_dir],
-		)
-		.generate_interface(&generated_glue_file);
-
-		// build java source path
-		let target = out_dir
-			.parent()
-			.unwrap()
-			.parent()
-			.unwrap()
-			.parent()
-			.unwrap()
-			.to_path_buf(); // target/debug
-
-		let mut java_target = target.clone(); // target/debug/java
-		java_target.push("java");
-
-		let mut pkg_path = java_target.clone(); // target/debug/java/src/com/codemp/intellij
-		pkg_path.push("src");
-		pkg_path.push(pkg_folder);
-
-		// delete folder if it exists, then create it
-		recreate_path(&pkg_path);
-
-		// generate java code
-		let java_cfg = flapigen::JavaConfig::new(pkg_path.clone(), pkg);
-		let java_gen = flapigen::Generator::new(flapigen::LanguageConfig::JavaConfig(java_cfg))
-			.rustfmt_bindings(true);
-		java_gen.expand_many(
-			"codemp-intellij",
-			&[&generated_glue_file, &typemap_file],
-			out_dir.join("glue.rs"),
-		);
-
-		#[cfg(feature = "java-artifact")]
-		{
-			// panic if no jdk
-			std::process::Command::new("javac")
-				.arg("--version")
-				.status()
-				.expect("java not found");
-
-			// compile java code
-			let mut java_compiled = java_target.clone(); // target/debug/java/classes
-			java_compiled.push("classes");
-			recreate_path(&java_compiled);
-
-			let mut javac_cmd = std::process::Command::new("javac");
-			javac_cmd.arg("-d").arg(java_compiled.as_os_str());
-			for java_file in pkg_path.read_dir().unwrap().filter_map(|e| e.ok()) {
-				javac_cmd.arg(java_file.path().as_os_str());
-			}
-			javac_cmd.status().expect("failed to run javac");
-
-			// jar it!
-			let mut jar_file = target.clone(); // target/debug/codemp-java.jar
-			jar_file.push("codemp-java.jar");
-
-			let mut jar_cmd = std::process::Command::new("jar");
-			jar_cmd
-				.current_dir(&java_compiled)
-				.arg("cf")
-				.arg(jar_file.as_os_str());
-			for java_file in java_compiled.read_dir().unwrap().filter_map(|e| e.ok()) {
-				let relative_path = java_file.path().clone();
-				let relative_path = relative_path.strip_prefix(&java_compiled).unwrap();
-				jar_cmd.arg(relative_path.as_os_str());
-			}
-			jar_cmd.status().expect("failed to run jar!");
-
-			println!("cargo:rerun-if-changed={}", generated_glue_file.display());
-		}
-	}
-
 	#[cfg(feature = "js")]
 	{
 		napi_build::setup();
@@ -103,11 +16,3 @@ fn main() {
 		pyo3_build_config::add_extension_module_link_args();
 	}
 }
-
-#[cfg(feature = "java")]
-fn recreate_path(path: &std::path::PathBuf) {
-	if path.exists() {
-		std::fs::remove_dir_all(path).expect("failed to delete old dir!");
-	}
-	std::fs::create_dir_all(path).expect("error while creating folder!");
-}

java/src/mp/code/BufferController.java

@@ -0,0 +1,39 @@
+package mp.code;
+
+import mp.code.data.TextChange;
+import mp.code.exceptions.CodeMPLibException;
+
+public class BufferController {
+	private final long ptr;
+
+	BufferController(long ptr) {
+		this.ptr = ptr;
+	}
+
+	public static native String get_name(long self);
+	public String getName() {
+		return get_name(this.ptr);
+	}
+
+	public static native String get_content(long self);
+	public String getContent() {
+		return get_content(this.ptr);
+	}
+
+	private static native TextChange try_recv(long self) throws CodeMPLibException;
+	public TextChange tryRecv() throws CodeMPLibException {
+		return try_recv(this.ptr);
+	}
+
+	private static native void send(long self, TextChange change) throws CodeMPLibException;
+	public void send(TextChange change) throws CodeMPLibException {
+		send(this.ptr, change);
+	}
+
+	private static native void free(long self);
+	@Override
+	@SuppressWarnings("removal")
+	protected void finalize() throws Throwable {
+		free(this.ptr);
+	}
+}

java/src/mp/code/Client.java

@@ -0,0 +1,64 @@
+package mp.code;
+
+import mp.code.exceptions.CodeMPLibException;
+
+import java.util.Optional;
+import java.util.UUID;
+
+public class Client {
+	private final long ptr;
+	private final String url;
+
+	private static native long setup_tracing(String path);
+
+	private static native long connect(String url) throws CodeMPLibException;
+	public Client(String url) throws CodeMPLibException {
+		this.ptr = connect(url);
+		this.url = url;
+	}
+
+	public String getUrl() {
+		return this.url;
+	}
+
+	private static native void login(long self, String username, String password, String workspace) throws CodeMPLibException;
+	public void login(String username, String password, String workspace) throws CodeMPLibException {
+		login(this.ptr, username, password, workspace);
+	}
+
+	private static native long join_workspace(long self, String id) throws CodeMPLibException;
+	public Workspace joinWorkspace(String id) throws CodeMPLibException {
+		return new Workspace(join_workspace(this.ptr, id));
+	}
+
+	private static native long get_workspace(long self);
+	public Optional<Workspace> getWorkspace() {
+		long ptr = get_workspace(this.ptr);
+		if(ptr == 0) { // TODO it would be better to init in rust directly
+			return Optional.empty();
+		} else {
+			return Optional.of(new Workspace(ptr));
+		}
+	}
+	
+	private static native void free(long self);
+	@Override
+	@SuppressWarnings("removal") // muh java 8
+	protected void finalize() {
+		free(this.ptr);
+	}
+
+	// TODO - remove everything past this line
+	public static void main(String[] args) throws CodeMPLibException {
+		Client c = new Client("http://alemi.dev:50053");
+		c.login(UUID.randomUUID().toString(), "lmaodefaultpassword", "glue");
+		c.joinWorkspace("glue");
+		System.out.println("Done!");
+	}
+	
+	static {
+		System.loadLibrary("codemp");
+		setup_tracing(null);
+	}
+}
+

java/src/mp/code/CursorController.java

@@ -0,0 +1,29 @@
+package mp.code;
+
+import mp.code.data.Cursor;
+import mp.code.data.TextChange;
+
+public class CursorController {
+	private final long ptr;
+
+	CursorController(long ptr) {
+		this.ptr = ptr;
+	}
+
+	private static native Cursor recv(long self);
+	public Cursor recv() {
+		return recv(this.ptr);
+	}
+
+	private static native void send(long self, Cursor cursor);
+	public void send(TextChange change, Cursor cursor) {
+		send(this.ptr, cursor);
+	}
+
+	private static native void free(long self);
+	@Override
+	@SuppressWarnings("removal")
+	protected void finalize() throws Throwable {
+		free(this.ptr);
+	}
+}

java/src/mp/code/Workspace.java

@@ -0,0 +1,70 @@
+package mp.code;
+
+import mp.code.exceptions.CodeMPLibException;
+
+public class Workspace {
+	private final long ptr;
+
+	Workspace(long ptr) {
+		this.ptr = ptr;
+	}
+
+	private static native String get_workspace_id(long self);
+	public String getWorkspaceId() {
+		return get_workspace_id(this.ptr);
+	}
+
+	private static native long get_cursor(long self);
+	public CursorController getCursor() {
+		return new CursorController(get_cursor(this.ptr));
+	}
+
+	private static native long get_buffer(long self, String path);
+	public BufferController getBuffer(String path) {
+		return new BufferController(get_buffer(this.ptr, path));
+	}
+
+	private static native void get_file_tree(long self);
+	public void getFileTree() {
+		// TODO vector?
+	}
+
+	private static native long create_buffer(String path) throws CodeMPLibException;
+	public BufferController createBuffer(String path) throws CodeMPLibException {
+		return new BufferController(create_buffer(path));
+	}
+
+	private static native long attach_to_buffer(long self) throws CodeMPLibException;
+	public BufferController attachToBuffer() throws CodeMPLibException {
+		return new BufferController(attach_to_buffer(ptr));
+	}
+
+	private static native void fetch_buffers(long self) throws CodeMPLibException;
+	public void fetchBuffers() throws CodeMPLibException {
+		fetch_buffers(this.ptr);
+	}
+
+	private static native void fetch_users(long self) throws CodeMPLibException;
+	public void fetchUsers() throws CodeMPLibException {
+		fetch_buffers(this.ptr);
+	}
+
+	private static native void list_buffer_users(long self, String path) throws CodeMPLibException;
+	public void listBufferUsers(String path) throws CodeMPLibException {
+		// TODO pass vector
+	}
+
+	private static native void delete_buffer(long self, String path) throws CodeMPLibException;
+	public void deleteBuffer(String path) throws CodeMPLibException {
+		delete_buffer(this.ptr, path);
+	}
+
+	// TODO select_buffer
+
+	private static native void free(long self);
+	@Override
+	@SuppressWarnings("removal")
+	protected void finalize() throws Throwable {
+		free(this.ptr);
+	}
+}

java/src/mp/code/data/Cursor.java

@@ -0,0 +1,16 @@
+package mp.code.data;
+
+public class Cursor {
+	public final int startRow, startCol, endRow, endCol;
+	public final String buffer;
+	public final String user;
+
+	public Cursor(int startRow, int startCol, int endRow, int endCol, String buffer, String user) {
+		this.startRow = startRow;
+		this.startCol = startCol;
+		this.endRow = endRow;
+		this.endCol = endCol;
+		this.buffer = buffer;
+		this.user = user;
+	}
+}

java/src/mp/code/data/TextChange.java

@@ -0,0 +1,13 @@
+package mp.code.data;
+
+public class TextChange {
+	public final long start;
+	public final long end;
+	public final String content;
+
+	public TextChange(long start, long end, String content) {
+		this.start = start;
+		this.end = end;
+		this.content = content;
+	}
+}

java/src/mp/code/exceptions/ChannelException.java

@@ -0,0 +1,7 @@
+package mp.code.exceptions;
+
+public class ChannelException extends CodeMPLibException {
+	public ChannelException(String input) {
+		super(input);
+	}
+}

java/src/mp/code/exceptions/CodeMPLibException.java

@@ -0,0 +1,10 @@
+package mp.code.exceptions;
+
+/**
+ * A generic class for all our exceptions coming through the JNI from the library.
+ */
+public abstract class CodeMPLibException extends Exception {
+	protected CodeMPLibException(String msg) {
+		super(msg);
+	}
+}

java/src/mp/code/exceptions/DeadlockedException.java

@@ -0,0 +1,7 @@
+package mp.code.exceptions;
+
+public class DeadlockedException extends CodeMPLibException {
+	public DeadlockedException(String s) {
+		super(s);
+	}
+}

java/src/mp/code/exceptions/InvalidStateException.java

@@ -0,0 +1,7 @@
+package mp.code.exceptions;
+
+public class InvalidStateException extends CodeMPLibException {
+    public InvalidStateException(String message) {
+        super(message);
+    }
+}

java/src/mp/code/exceptions/TransportException.java

@@ -0,0 +1,7 @@
+package mp.code.exceptions;
+
+public class TransportException extends CodeMPLibException {
+    public TransportException(String message) {
+        super(message);
+    }
+}

src/ffi/java/client.rs

@@ -0,0 +1,86 @@
+use jni::{objects::{JClass, JString}, sys::jlong, JNIEnv};
+use crate::{client::Client, Workspace};
+
+use super::{util::JExceptable, RT};
+
+/// Called by the Java GC to drop a [Client].
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Client_free(_env: JNIEnv, _class: JClass, input: jlong) {
+	super::util::dereference_and_drop::<Client>(input)
+}
+
+/// Sets up tracing subscriber
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Client_setup_1tracing<'local>(
+	mut env: JNIEnv,
+	_class: JClass<'local>,
+	path: JString<'local>
+) {
+	let path: Option<String> = if path.is_null() {
+		None
+	} else {
+		Some(env.get_string(&path).expect("Couldn't get java string!").into())
+	};
+
+	super::setup_logger(true, path);
+}
+
+/// Connects to a given URL and returns a [Client] to interact with that server.
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Client_connect<'local>(
+	mut env: JNIEnv,
+	_class: JClass<'local>,
+	input: JString<'local>
+) -> jlong {
+	let url: String = env.get_string(&input).expect("Couldn't get java string!").into();
+	RT.block_on(crate::Client::new(&url))
+		.map(|client| Box::into_raw(Box::new(client)) as jlong)
+		.jexcept(&mut env)
+}
+
+/// Logs in to a specific [Workspace].
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Client_login<'local>(
+	mut env: JNIEnv<'local>,
+	_class: JClass<'local>,
+	self_ptr: jlong,
+	user: JString<'local>,
+	pwd: JString<'local>,
+	workspace: JString<'local>
+) {
+	let client = unsafe { Box::leak(Box::from_raw(self_ptr as *mut Client)) };
+	let user: String = env.get_string(&user).expect("Couldn't get java string!").into();
+	let pwd: String = env.get_string(&pwd).expect("Couldn't get java string!").into();
+	let workspace: String = env.get_string(&workspace).expect("Couldn't get java string!").into();
+	RT.block_on(client.login(user, pwd, Some(workspace)))
+		.jexcept(&mut env)
+}
+
+/// Joins a [Workspace] and returns a pointer to it.
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Client_join_1workspace<'local>(
+	mut env: JNIEnv<'local>,
+	_class: JClass<'local>,
+	self_ptr: jlong,
+	input: JString<'local>
+) -> jlong {
+	let client  = unsafe { Box::leak(Box::from_raw(self_ptr as *mut Client)) };
+	let workspace_id = unsafe { env.get_string_unchecked(&input).expect("Couldn't get java string!") };
+	RT.block_on(client.join_workspace(workspace_id.to_str().expect("Not UTF-8")))
+		.map(|workspace| spawn_updater(workspace.clone()))
+		.map(|workspace| Box::into_raw(Box::new(workspace)) as jlong)
+		.jexcept(&mut env)
+}
+
+// TODO: this stays until we get rid of the arc then i'll have to find a better way
+fn spawn_updater(workspace: Workspace) -> Workspace {
+	let w = workspace.clone();
+	RT.spawn(async move {
+		loop {
+			tokio::time::sleep(std::time::Duration::from_secs(60)).await;
+			w.fetch_buffers().await.unwrap();
+			w.fetch_users().await.unwrap();
+		}
+	});
+	workspace
+}

src/ffi/java/mod.rs

@@ -1,333 +1,33 @@
-use api::Controller;
+pub mod client;
-use codemp_proto::{cursor::{RowCol, CursorPosition}, files::BufferNode};
+pub mod workspace;
-use rifgen::rifgen_attr::{generate_access_methods, generate_interface, generate_interface_doc};
+pub mod util;
-use std::sync::Arc;
-use std::time::Duration;
-use uuid::Uuid;
-
-use crate::{
-	Client,
-	Error,
-	Result,
-	api::TextChange,
-	buffer::{self, tools},
-	cursor,
-	workspace::Workspace
-};
-
-//rifgen generated code
-include!(concat!(env!("OUT_DIR"), "/glue.rs"));
 
 lazy_static::lazy_static! {
-	/// the tokio runtime, since we can't easily have Java and Rust async work together
+	pub(crate) static ref RT: tokio::runtime::Runtime = tokio::runtime::Runtime::new().expect("could not create tokio runtime");
-	static ref RT: tokio::runtime::Runtime = tokio::runtime::Runtime::new()
-		.expect("could not start tokio runtime");
 }
 
-#[generate_interface_doc]
+pub(crate) fn setup_logger(debug: bool, path: Option<String>) {
-/// the handler class that represent an instance of a CodeMP client
+	let format = tracing_subscriber::fmt::format()
-struct ClientHandler {
+		.with_level(true)
-	client: Client,
+		.with_target(true)
-	url: String,
+		.with_thread_ids(false)
-}
+		.with_thread_names(false)
+		.with_ansi(false)
+		.with_file(false)
+		.with_line_number(false)
+		.with_source_location(false)
+		.compact();
 
-impl ClientHandler {
+	let level = if debug { tracing::Level::DEBUG } else {tracing::Level::INFO };
-	#[generate_interface(constructor)]
-	/// construct a new [ClientHandler]
-	fn new(address: &str) -> ClientHandler {
-		ClientHandler {
-			client: RT.block_on(Client::new(address)).unwrap(),
-			url: address.to_string(),
-		}
-	}
 
-	#[generate_interface]
+	let builder = tracing_subscriber::fmt()
-	/// join a workspace by name
+		.event_format(format)
-	fn join_workspace(&mut self, workspace_id: &str) -> Result<WorkspaceHandler> {
+		.with_max_level(level);
-		RT.block_on(self.client.join_workspace(workspace_id))
-			.map(|workspace| {
-				Self::spawn_updater(workspace.clone());
-				WorkspaceHandler { workspace }
-			})
-	}
 
-	fn spawn_updater(workspace: Arc<Workspace>) {
+	if let Some(path) = path {
-		tokio::spawn(async move {
+		let logfile = std::fs::File::create(path).expect("failed creating logfile");
-			loop {
+		builder.with_writer(std::sync::Mutex::new(logfile)).init();
-				tokio::time::sleep(Duration::from_secs(60)).await;
+	} else {
-				workspace.fetch_buffers().await.unwrap();
+		builder.with_writer(std::sync::Mutex::new(std::io::stdout())).init();
-				workspace.fetch_users().await.unwrap();
-			}
-		});
-	}
-
-	#[generate_interface]
-	/// get the url you are currently connected to
-	fn get_url(&self) -> String {
-		self.url.clone()
-	}
-}
-
-#[generate_interface_doc]
-/// wraps a [codemp::workspace::Workspace] to be handled by Java
-struct WorkspaceHandler {
-	workspace: Arc<Workspace>,
-}
-
-impl WorkspaceHandler { // TODO: workspace leave / buffer detach ?
-	#[generate_interface(constructor)]
-	/// constructor required by flapigen, DO NOT CALL THIS
-	fn new() -> WorkspaceHandler {
-		unimplemented!()
-	}
-
-	#[generate_interface]
-	/// create a new buffer in current workspace
-	fn create_buffer(&mut self, path: &str) -> Result<BufferHandler> {
-		RT.block_on(self.workspace.create(path))?;
-		Ok(self.get_buffer(path).unwrap())
-	}
-
-	#[generate_interface]
-	/// attach to a buffer and get a [crate::BufferHandler] for it
-	fn attach_to_buffer(&mut self, path: &str) -> Result<BufferHandler> {
-		RT.block_on(self.workspace.attach(path))
-			.map(|buffer| BufferHandler { buffer })
-	}
-
-	#[generate_interface]
-	/// updates the local list of the workspace's buffers
-	fn fetch_buffers(&mut self) -> Result<()> {
-		RT.block_on(self.workspace.fetch_buffers())
-	}
-
-	#[generate_interface]
-	/// updates the local list of the workspace's users
-	fn fetch_users(&mut self) -> Result<()> {
-		RT.block_on(self.workspace.fetch_users())
-	}
-
-	#[generate_interface]
-	/// gets a list of all users in a buffer
-	fn list_buffer_users(&mut self, path: &str) -> Result<StringVec> {
-		let mut res = StringVec::new();
-		RT.block_on(self.workspace.list_buffer_users(path))?
-			.iter()
-			.for_each(|u| res.push(Uuid::from(u.clone()).to_string()));
-		Ok(res)
-	}
-
-	#[generate_interface]
-	/// delete a buffer
-	fn delete_buffer(&mut self, path: &str) -> Result<()> {
-		RT.block_on(self.workspace.delete(path))
-	}
-
-	#[generate_interface]
-	/// get the workspace id
-	fn get_workspace_id(&self) -> String {
-		self.workspace.id().clone()
-	}
-
-	#[generate_interface]
-	/// get a [crate::CursorHandler] for the workspace's cursor
-	fn get_cursor(&self) -> CursorHandler {
-		CursorHandler {
-			cursor: self.workspace.cursor().clone(),
-		}
-	}
-
-	#[generate_interface]
-	/// get a [crate::BufferHandler] for one of the workspace's buffers
-	fn get_buffer(&self, path: &str) -> Option<BufferHandler> {
-		self.workspace
-			.buffer_by_name(path)
-			.map(|buffer| BufferHandler { buffer })
-	}
-
-	#[generate_interface]
-	/// get the names of all buffers available in the workspace
-	fn get_filetree(&self) -> StringVec {
-		StringVec {
-			v: self.workspace.filetree()
-		}
-	}
-
-	#[generate_interface]
-	/// polls a list of buffers, returning the first ready one
-	fn select_buffer(
-		&mut self,
-		mut buffer_ids: StringVec,
-		timeout: i64,
-	) -> Result<Option<BufferHandler>> {
-		let mut buffers = Vec::new();
-		for id in buffer_ids.v.iter_mut() {
-			match self.get_buffer(id.as_str()) {
-				Some(buf) => buffers.push(buf.buffer),
-				None => continue,
-			}
-		}
-
-		let result = RT.block_on(tools::select_buffer(
-			buffers.as_slice(),
-			Some(Duration::from_millis(timeout as u64)),
-		));
-
-		match result {
-			Err(e) => Err(e),
-			Ok(buffer) => Ok(buffer.map(|buffer| BufferHandler { buffer })),
-		}
-	}
-}
-
-#[generate_interface_doc]
-#[generate_access_methods]
-/// wraps a [codemp::proto::cursor::CursorEvent] to be handled by Java
-struct CursorEventWrapper {
-	user: String,
-	buffer: String,
-	start_row: i32,
-	start_col: i32,
-	end_row: i32,
-	end_col: i32,
-}
-
-#[generate_interface_doc]
-/// a handler providing Java access to [codemp::cursor::Controller] methods
-struct CursorHandler {
-	pub cursor: Arc<cursor::Controller>,
-}
-
-impl CursorHandler {
-	#[generate_interface(constructor)]
-	/// constructor required by flapigen, DO NOT CALL THIS
-	fn new() -> CursorHandler {
-		unimplemented!()
-	}
-
-	#[generate_interface]
-	/// get next cursor event from current workspace, or block until one is available
-	fn recv(&self) -> Result<CursorEventWrapper> {
-		match RT.block_on(self.cursor.recv()) {
-			Err(err) => Err(err),
-			Ok(event) => Ok(CursorEventWrapper {
-				user: Uuid::from(event.user).to_string(),
-				buffer: event.position.buffer.path.clone(),
-				start_row: event.position.start.row,
-				start_col: event.position.start.col,
-				end_row: event.position.end.row,
-				end_col: event.position.end.col,
-			}),
-		}
-	}
-
-	#[generate_interface]
-	/// broadcast a cursor event
-	/// will automatically fix start and end if they are accidentally inverted
-	fn send(
-		&self,
-		buffer: String,
-		start_row: i32,
-		start_col: i32,
-		end_row: i32,
-		end_col: i32,
-	) -> Result<()> {
-		self.cursor.send(CursorPosition {
-			buffer: BufferNode { path: buffer },
-			start: RowCol::from((start_row, start_col)),
-			end: RowCol::from((end_row, end_col)),
-		})
-	}
-}
-
-#[generate_interface_doc]
-#[generate_access_methods]
-/// wraps a [codemp::api::change::TextChange] to make it accessible from Java
-struct TextChangeWrapper {
-	start: usize,
-	end: usize, //not inclusive
-	content: String,
-}
-
-#[generate_interface_doc]
-/// a handler providing Java access to [codemp::buffer::Controller] methods
-struct BufferHandler {
-	pub buffer: Arc<buffer::Controller>,
-}
-
-impl BufferHandler {
-	#[generate_interface(constructor)]
-	/// constructor required by flapigen, DO NOT CALL THIS
-	fn new() -> BufferHandler {
-		unimplemented!()
-	}
-
-	#[generate_interface]
-	/// get the name of the buffer
-	fn get_name(&self) -> String {
-		self.buffer.name().to_string()
-	}
-
-	#[generate_interface]
-	/// get the contents of the buffer
-	fn get_content(&self) -> String {
-		self.buffer.content()
-	}
-
-	#[generate_interface]
-	/// if a text change is available on the buffer, return it immediately
-	fn try_recv(&self) -> Result<Option<TextChangeWrapper>> {
-		match self.buffer.try_recv() {
-			Err(err) => Err(err),
-			Ok(None) => Ok(None),
-			Ok(Some(change)) => Ok(Some(TextChangeWrapper {
-				start: change.span.start,
-				end: change.span.end,
-				content: change.content.clone(),
-			})),
-		}
-	}
-
-	#[generate_interface]
-	/// broadcast a text change on the buffer
-	fn send(&self, start_offset: usize, end_offset: usize, content: String) -> Result<()> {
-		self.buffer.send(TextChange {
-			span: start_offset..end_offset,
-			content,
-		})
-	}
-}
-
-#[generate_interface_doc]
-/// a convenience struct allowing Java access to a Rust vector
-struct StringVec {
-	//jni moment
-	v: Vec<String>,
-}
-
-impl StringVec {
-	#[generate_interface(constructor)]
-	/// initialize an empty vector
-	fn new() -> StringVec {
-		Self { v: Vec::new() }
-	}
-
-	#[generate_interface]
-	/// push a new value onto the vector
-	fn push(&mut self, s: String) {
-		self.v.push(s);
-	}
-
-	#[generate_interface]
-	/// get the length of the underlying vector
-	fn length(&self) -> i64 {
-		self.v.len() as i64
-	}
-
-	#[generate_interface]
-	/// access the element at a given index
-	fn get(&self, idx: i64) -> Option<String> {
-		let elem: Option<&String> = self.v.get(idx as usize);
-		elem.map(|s| s.clone())
 	}
 }

src/ffi/java/typemap.in

@@ -1,39 +0,0 @@
-foreign_typemap!( //thanks @tasn on GitHub for the idea
-	($p:r_type) <T> Result<T> => swig_i_type!(T) {
-		$out = match $p {
-			Ok(x) => {
-				swig_from_rust_to_i_type!(T, x, ret)
-				ret
-			}
-			Err(err) => {
-				let (msg, exception_class) = match err {
-					Error::Filler { message } => (
-						message,
-						swig_jni_find_class!(CODEMP_EXCEPTION, "com/codemp/intellij/exceptions/CodeMPException")
-					),
-					Error::Transport { status, message } => (
-						format!("Status {}: {}", status, message),
-						swig_jni_find_class!(TRANSPORT_EXCEPTION, "com/codemp/intellij/exceptions/lib/TransportException")
-					),
-					Error::InvalidState { msg } => (
-						msg, swig_jni_find_class!(INVALID_STATE_EXCEPTION, "com/codemp/intellij/exceptions/lib/InvalidStateException")
-					),
-					Error::Deadlocked => (
-						"WOOT deadlocked (safe to retry)!".to_string(),
-						swig_jni_find_class!(DEADLOCKED_EXCEPTION, "com/codemp/intellij/exceptions/lib/DeadlockedException")
-					),
-					Error::Channel { send } => {
-						let verb = if send { "sending" } else { "reading" };
-						(
-							format!("Error while {} message on channel: the channel was closed!", verb),
-							swig_jni_find_class!(CHANNEL_EXCEPTION, "com/codemp/intellij/exceptions/lib/ChannelException")
-						)
-					}
-				};
-				jni_throw(env, exception_class, &msg);
-				return <swig_i_type!(T)>::jni_invalid_value();
-			}
-		};
-	};
-	($p:f_type, unique_prefix="/*err*/") => "/*err*/swig_f_type!(T)" "swig_foreign_from_i_type!(T, $p)";
-);

src/ffi/java/util.rs

@@ -0,0 +1,29 @@
+use jni::{JNIEnv, sys::jlong};
+
+/// A simple utility method that converts a pointer back into a [Box] and then drops it.
+pub(crate) fn dereference_and_drop<T>(ptr: jlong) {
+	let client : Box<T> = unsafe { Box::from_raw(ptr as *mut T) };
+	std::mem::drop(client)
+}
+
+/// A trait meant for our [crate::Result] type to make converting it to Java easier.
+pub(crate) trait JExceptable<T> {
+	/// Unwraps it and throws an appropriate Java exception if it's an error.
+	/// Theoretically it returns the type's default value, but the exception makes the value ignored.
+	fn jexcept(self, env: &mut JNIEnv) -> T;
+}
+
+impl<T> JExceptable<T> for crate::Result<T> where T: Default {
+	fn jexcept(self, env: &mut JNIEnv) -> T {
+		if let Err(err) = &self {
+			let msg = format!("{err}");
+			match err {
+				crate::Error::InvalidState { .. } => env.throw_new("mp/code/exceptions/InvalidStateException", msg),
+				crate::Error::Deadlocked => env.throw_new("mp/code/exceptions/DeadlockedException", msg),
+				crate::Error::Transport { .. } => env.throw_new("mp/code/exceptions/TransportException", msg),
+				crate::Error::Channel { .. } => env.throw_new("mp/code/exceptions/ChannelException", msg)
+			}.expect("Failed to throw exception!");
+		}
+		self.unwrap_or_default()
+	}
+}

src/ffi/java/workspace.rs

@@ -0,0 +1,23 @@
+use jni::{objects::{JClass, JString}, sys::jlong, JNIEnv};
+use crate::{Client, Workspace};
+
+use super::{util::JExceptable, RT};
+
+/// Called by the Java GC to drop a [Workspace].
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Workspace_free(_env: JNIEnv, _class: JClass, input: jlong) {
+	super::util::dereference_and_drop::<Client>(input)
+}
+
+/// Creates a [Buffer]
+#[no_mangle]
+pub extern "system" fn Java_mp_code_Workspace_create_1buffer<'local>(
+	mut env: JNIEnv,
+	_class: JClass<'local>,
+	self_ptr: jlong,
+	input: JString<'local>
+) {
+	let ws: Box<Workspace> = unsafe { Box::from_raw(self_ptr as *mut Workspace) };
+	let path: String = env.get_string(&input).expect("Couldn't get java string!").into();
+	RT.block_on(ws.create(&path)).jexcept(&mut env);
+}