Rafael Sanchez Rafael Sanchez - 10 months ago 216
Java Question

Error trying to use GSON with own class

I'm trying to use Google's GSON for the first time in my Android app. I want to use GSON with a class called

, which keeps most of my ArrayList, booleans, Strings and other basic objects in one place. My goal is to save an instance of
. I wrote:

Gson gson = new Gson();
String userValuesJSON=gson.toJson(userValues);
getSharedPreferences(myAppKey, MODE_PRIVATE).edit().putString("JSON", userValuesJSON).commit();

The error I get:

java.lang.SecurityException: Can't make method constructor accessible
at java.lang.reflect.Constructor.setAccessible(Constructor.java:336)
at com.google.gson.internal.ConstructorConstructor.newDefaultConstructor(ConstructorConstructor.java:97)
at com.google.gson.internal.ConstructorConstructor.get(ConstructorConstructor.java:79)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:71)
at com.google.gson.Gson.getAdapter(Gson.java:356)

when I added GSON I added the following to

repositories {

dependencies {
compile 'com.google.code.gson:gson:2.2.4'

Any brainstorming greatly appreciated!

EDIT: This is how the constructor looks like:

public class UserValues implements Serializable {

private Integer period;
private Float fee;
private ArrayList<Boolean> theBooleans = new ArrayList<>();
private ArrayList<Integer> theIntegers = new ArrayList<>();
private static final ArrayList<String> theIntegerKeys = new ArrayList<>();
private static final ArrayList<String> theBooleanKeys = new ArrayList<>();
public static final String myAppKey = "Investor Playground";
private static final ArrayList<Integer> theIntDefValues = new ArrayList<>();
private ArrayList<Float> arrayList;
private ArrayList<ArrayList<Integer>> theDates;
private ArrayList<Float> strategyResult;
private int theCurrentFragment;

private int theCurrentGraph;

Context context;

public UserValues(Context context_) {



add an empty constructor to the class as this will only be used to set values this should not cause any issues if the context is not initialised

public UserValues() {