Helper class to parse error response body on Retrofit 2

ExceptionParser.java

public static class ExceptionParser {
    private final ResponseBody body;
    private final String bodyString;
    private final Converter.Factory converterFactory;

    public ExceptionParser(Response response, Converter.Factory converterFactory) {
        this.converterFactory = converterFactory;
        this.body = cloneResponseBody(response.errorBody());
        this.bodyString = getBodyAsString(body);
    }

    public <T> T getBodyAs(Type type) {
        if (body == null) {
            return null;
        }
        try {
            //noinspection unchecked
            return (T) converterFactory.fromResponseBody(type, new Annotation[0]).convert(body);
        } catch (JsonProcessingException e) {
            Log.e(TAG, "Failed to parse error response as JSON", e);
            return null;
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    public String getBodyAsString() {
        return bodyString;
    }

    @Nullable
    private static String getBodyAsString(@Nullable ResponseBody responseBody) {
        if (responseBody == null) {
            return null;
        }
        try {
            return responseBody.string();
        } catch (IOException e) {
            Log.w(TAG, "Failed to read error ResponseBody as String");
            return null;
        }
    }

    @Nullable
    private static ResponseBody cloneResponseBody(@Nullable final ResponseBody body) {
        if (body == null) {
            return null;
        }
        final Buffer buffer = new Buffer();
        try {
            BufferedSource source = body.source();
            buffer.writeAll(source);
            source.close();
        } catch (IOException e) {
            Log.w(TAG, "Failed to clone ResponseBody");
            return null;
        }
        return new ResponseBody() {
            @Override
            public MediaType contentType() {
                return body.contentType();
            }

            @Override
            public long contentLength() {
                return buffer.size();
            }

            @Override
            public BufferedSource source() {
                return buffer.clone();
            }
        };
    }
}

how do we use it?

No such method fromResponseBody()