无法从资产文件夹Android读取.json文件

Question

我正在尝试从asstes文件夹android中读取json文件，但我无法读取它，即使在读取行后我的日志也无法显示，任何人都可以告诉我怎么了吗？ 这是我的代码：公共类MapsActivity扩展FragmentActivity实现OnMapReadyCallback {

        private GoogleMap mMap;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_maps);
            // Obtain the SupportMapFragment and get notified when the map is ready to be used.
            SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                    .findFragmentById(R.id.map);
            mapFragment.getMapAsync(this);

            loadJSONFromAsset();
        }

        public String loadJSONFromAsset() {

            String json = null;
            try {

                Log.d("entry", "loadJSONFromAsset: "+json);

                InputStream is = getAssets().open("data.json");

                int size = is.available();

                byte[] buffer = new byte[size];

                is.read(buffer);

                is.close();

                json = new String(buffer, "UTF-8");

                Log.d("json", "loadJSONFromAsset: "+json);


            } catch (IOException ex) {
                Log.d("error", "loadJSONFromAsset: "+ex.toString());
                ex.printStackTrace();
                return null;
            }
            return json;


        }

    here is the log:
    07-10 22:38:53.174 9783-9783/com.nodapp D/entry: loadJSONFromAsset: null
                                                     }
    07-10 22:38:53.174 9783-9783/com.nodapp I/ViewRootImpl: CPU Rendering VSync enable = true
    07-10 22:38:53.174 9783-9783/com.nodapp W/IInputConnectionWrapper: getExtractedText on inactive InputConnection
    07-10 22:38:53.204 9783-9783/com.nodapp W/IInputConnectionWrapper: getTextBeforeCursor on inactive InputConnection
    07-10 22:38:53.234 9783-9783/com.nodapp W/IInputConnectionWrapper: getSelectedText on inactive InputConnection
    07-10 22:38:53.234 9783-9783/com.nodapp I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@d3ecf3 time:24068058
    07-10 22:38:53.314 9783-9783/com.nodapp W/IInputConnectionWrapper: getTextAfterCursor on inactive InputConnection

Answer 1

尝试这个：

public String loadJSONFromAsset() {

    String json = null;
    try {

        Log.d("entry", "loadJSONFromAsset: "+json);

        InputStream is = getAssets().open("data.json");

        StringBuilder buf=new StringBuilder();
        BufferedReader in=
        new BufferedReader(new InputStreamReader(is, "UTF-8"));
        String str;

        while ((str=in.readLine()) != null) {
            buf.append(str);
        }

        in.close();

        json = buf.toString();

        Log.d("json", "loadJSONFromAsset: "+json);

    } catch (IOException ex) {
        Log.d("error", "loadJSONFromAsset: "+ex.toString());
        ex.printStackTrace();
        return null;
    }
    return json;
}