Refactor the JNI interface to make it more modular and maintainable (#802)

sherpa-onnx/kotlin-api/WaveReader.kt

@@ -0,0 +1,29 @@
+// Copyright (c)  2023  Xiaomi Corporation
+package com.k2fsa.sherpa.onnx
+
+import android.content.res.AssetManager
+
+class WaveReader {
+    companion object {
+        // Read a mono wave file asset
+        // The returned array has two entries:
+        //  - the first entry contains an 1-D float array
+        //  - the second entry is the sample rate
+        external fun readWaveFromAsset(
+            assetManager: AssetManager,
+            filename: String,
+        ): Array<Any>
+
+        // Read a mono wave file from disk
+        // The returned array has two entries:
+        //  - the first entry contains an 1-D float array
+        //  - the second entry is the sample rate
+        external fun readWaveFromFile(
+            filename: String,
+        ): Array<Any>
+
+        init {
+            System.loadLibrary("sherpa-onnx-jni")
+        }
+    }
+}