package com.example.app; import android.os.Bundle; import android.app.Activity; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } public String getMessage() { return "Hello"; } public int add(int a, int b) { return a + b; } } まず、src/配下に「instrumentTest」ディレクトリを作成します