Add native instance wrapper interface / Clean up code

.gitignore

@@ -41,6 +41,8 @@ captures/
 *.jks
 crowdin.properties
 
+# C++
+.cxx/
+
 # AndroidX Room schema JSONs
 /app/schemas/
-/app/.cxx/

app/src/main/cpp/CMakeLists.txt

@@ -17,7 +17,6 @@ add_library(
         SHARED
 
         # Sources
-        native-lib.cpp
         dev_patrickgold_florisboard_ime_nlp_SuggestionList.cpp
 )
 

app/src/main/cpp/dev_patrickgold_florisboard_ime_nlp_SuggestionList.cpp

@@ -25,8 +25,8 @@ Java_dev_patrickgold_florisboard_ime_nlp_SuggestionList_00024Companion_nativeIni
         JNIEnv *env,
         jobject thiz,
         jint max_size) {
-    auto *stagedSuggestionList = new SuggestionList(max_size);
-    return reinterpret_cast<jlong>(stagedSuggestionList);
+    auto *suggestionList = new SuggestionList(max_size);
+    return reinterpret_cast<jlong>(suggestionList);
 }
 
 extern "C"
@@ -99,6 +99,6 @@ Java_dev_patrickgold_florisboard_ime_nlp_SuggestionList_00024Companion_nativeSiz
         JNIEnv *env,
         jobject thiz,
         jlong native_ptr) {
-    auto *stagedSuggestionList = reinterpret_cast<SuggestionList *>(native_ptr);
-    return stagedSuggestionList->size();
+    auto *suggestionList = reinterpret_cast<SuggestionList *>(native_ptr);
+    return suggestionList->size();
 }

app/src/main/cpp/native-lib.cpp

@@ -1,10 +0,0 @@
-#include <jni.h>
-#include <string>
-
-extern "C" JNIEXPORT jstring JNICALL
-Java_dev_patrickgold_florisboard_ime_core_FlorisBoard_jniHelloWorld(
-        JNIEnv* env,
-        jobject /* this */) {
-    std::string hello = "Hello from C++";
-    return env->NewStringUTF(hello.c_str());
-}

app/src/main/java/dev/patrickgold/florisboard/ime/core/FlorisBoard.kt

@@ -146,8 +146,6 @@ class FlorisBoard : InputMethodService(), LifecycleOwner, FlorisClipboardManager
 
     lateinit var asyncExecutor: ExecutorService
 
-    external fun jniHelloWorld(): String
-
     companion object {
         @Synchronized
         fun getInstance(): FlorisBoard {
@@ -194,7 +192,7 @@ class FlorisBoard : InputMethodService(), LifecycleOwner, FlorisClipboardManager
                     .build()
             )
         }*/
-        flogInfo(LogTopic.IMS_EVENTS) { jniHelloWorld() }
+        flogInfo(LogTopic.IMS_EVENTS)
         serviceLifecycleDispatcher.onServicePreSuperOnCreate()
 
         imeManager = getSystemService(Context.INPUT_METHOD_SERVICE) as? InputMethodManager

app/src/main/java/dev/patrickgold/florisboard/ime/core/NativeInstanceWrapper.kt

@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2021 Patrick Goldinger
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dev.patrickgold.florisboard.ime.core
+
+/**
+ * Type alias for a native pointer.
+ */
+typealias NativePtr = Long
+
+/**
+ * Constant value for a native null pointer.
+ */
+const val NATIVE_NULLPTR: NativePtr = 0
+
+/**
+ * Generic interface for a native instance object. Defines the basic
+ * methods which each native instance wrapper should define and be able
+ * to handle to.
+ */
+interface NativeInstanceWrapper {
+    /**
+     * Returns the native pointer of this instance. The returned pointer
+     * is only valid if [dispose] has not been previously called.
+     *
+     * @return The native null pointer for this instance.
+     */
+    fun nativePtr(): NativePtr
+
+    /**
+     * Deletes the native object and frees allocated resources. After
+     * invoking this method one MUST NOT touch this instance ever again.
+     */
+    fun dispose()
+}

app/src/main/java/dev/patrickgold/florisboard/ime/nlp/SuggestionList.kt

@@ -16,10 +16,13 @@
 
 package dev.patrickgold.florisboard.ime.nlp
 
+import dev.patrickgold.florisboard.ime.core.NativeInstanceWrapper
+import dev.patrickgold.florisboard.ime.core.NativePtr
+
 @JvmInline
 value class SuggestionList private constructor(
-    private val nativePtr: NativePtr
-) : Collection<String> {
+    private val _nativePtr: NativePtr
+) : Collection<String>, NativeInstanceWrapper {
     companion object {
         fun new(maxSize: Int): SuggestionList {
             val nativePtr = nativeInitialize(maxSize)
@@ -37,18 +40,18 @@ value class SuggestionList private constructor(
     }
 
     override val size: Int
-        get() = nativeSize(nativePtr)
+        get() = nativeSize(_nativePtr)
 
     fun add(word: Word, freq: Freq): Boolean {
-        return nativeAdd(nativePtr, word, freq)
+        return nativeAdd(_nativePtr, word, freq)
     }
 
     fun clear() {
-        nativeClear(nativePtr)
+        nativeClear(_nativePtr)
     }
 
     override fun contains(element: Word): Boolean {
-        return nativeContains(nativePtr, element)
+        return nativeContains(_nativePtr, element)
     }
 
     override fun containsAll(elements: Collection<Word>): Boolean {
@@ -67,7 +70,7 @@ value class SuggestionList private constructor(
     }
 
     fun getOrNull(index: Int): Word? {
-        return nativeGetOrNull(nativePtr, index)
+        return nativeGetOrNull(_nativePtr, index)
     }
 
     override fun isEmpty(): Boolean = size <= 0
@@ -76,8 +79,12 @@ value class SuggestionList private constructor(
         return SuggestionListIterator(this)
     }
 
-    fun dispose() {
-        nativeDispose(nativePtr)
+    override fun nativePtr(): NativePtr {
+        return _nativePtr
+    }
+
+    override fun dispose() {
+        nativeDispose(_nativePtr)
     }
 
     class SuggestionListIterator internal constructor (

app/src/main/java/dev/patrickgold/florisboard/ime/nlp/nlp.kt

@@ -16,7 +16,6 @@
 
 package dev.patrickgold.florisboard.ime.nlp
 
-typealias NativePtr = Long
 typealias Word = String
 typealias Freq = Int