MyJSONParser.java

package com.android.example;

import java.lang.reflect.Array;
import java.lang.reflect.Field;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

public class MyJSONParser {

    public static Object populateObjectFromJSON(Class<?> classname, JSONObject js) {
        Object obj = null;
        System.out.println("Populating " + classname.getSimpleName()+ " -with- " + js.toString());
        try {
            obj = classname.newInstance();
        } catch (InstantiationException e1) {
            System.err.println(e1.getMessage());
            return null;
        } catch (IllegalAccessException e1) {
            System.err.println(e1.getMessage());
            return null;
        }

        Field[] fields = classname.getFields();
        for (Field f : fields) {
            try {
                if (js.has(f.getName())) {
                        String type = f.getType().getSimpleName();
                    if (type.equalsIgnoreCase("boolean")) {
                        f.setBoolean(obj, js.getBoolean(f.getName()));
                    } else if (type.equalsIgnoreCase("int")) {
                        f.setInt(obj, js.getInt(f.getName()));
                    } else if (type.equalsIgnoreCase("double")) {
                        f.setDouble(obj, js.getDouble(f.getName()));
                    } else if (type.equalsIgnoreCase("float")) {
                        f.setFloat(obj, (float) js.getDouble(f.getName()));
                    } else if (type.equalsIgnoreCase("string")) {
                        f.set(obj, js.getString(f.getName()));
                    } else if (f.getType().isArray()) {
                        // System.out.println("This is an ARRAY: " + f.getName());
                        insertArrayFromJSON(obj, f, js.getJSONArray(f.getName()));
                    } else {
                        f.set(obj,populateObjectFromJSON(f.getType(),js.getJSONObject(f.getName())));
                    }
                }
            } catch (IllegalArgumentException e) {
                System.err.println(e.getMessage());
            } catch (IllegalAccessException e) {
                System.err.println(e.getMessage());
            } catch (JSONException e) {
                System.err.println(e.getMessage());
            }
        }

        return obj;
    }

    public static void insertArrayFromJSON(Object obj, Field f, JSONArray js, int pos) throws IllegalArgumentException, NegativeArraySizeException, IllegalAccessException, JSONException {
        f.set(obj,Array.newInstance(f.getType().getComponentType(), js.length()));
        String type = f.getType().getComponentType().getSimpleName();

        for (int i = 0; i < js.length(); i++) {
            if (f.getType().getComponentType().isArray()) {
                System.out.println("An array!! " + f.getName());
                //TO-DO
            } else if (!f.getType().getComponentType().isPrimitive()&& (!type.equalsIgnoreCase("string"))) {
                //System.out.println(f.getType().getSimpleName() + " isn't primitive " + f.getName());
                Array.set(f.get(obj),i,populateObjectFromJSON(f.getType().getComponentType(),js.getJSONObject(i)));
                //Array.set(f.get(obj),i,populateObjectFromJSON(f.getType().getComponentType(), new JSONObject(js.getJSONArray(i).toString())));
            } else {
                //Primitive
                Array.set(f.get(obj), i, js.get(i));
            }
        }
    }

    public static JSONObject parseObjectToJSONClass(Object obj) {JSONObject js = new JSONObject();
        Class<?> c = obj.getClass();
        Field[] fields = c.getFields();

        for (Field f : fields) {
            try {
            System.out.println(f.getName() + " - "+ f.getType().getSimpleName() + " - " + f.get(obj));

            String name = f.getName();
            String type = f.getType().getSimpleName();
            if (f.get(obj) != null) {
                if (type.equalsIgnoreCase("boolean")) {
                    js.put(name, f.getBoolean(obj));
                } else if (type.equalsIgnoreCase("int")) {
                    js.put(name, f.getInt(obj));
                } else if (type.equalsIgnoreCase("double")) {
                    js.put(name, f.getDouble(obj));
                } else if (type.equalsIgnoreCase("float")) {
                    js.put(name, f.getFloat(obj));
                } else if (type.equalsIgnoreCase("string")) {
                    js.put(name, (String) f.get(obj));
                } else if (type.endsWith("]")) {
                    JSONArray ar = new JSONArray();
                    for (int i = 0; i < Array.getLength(f.get(obj)); i++) {
                        ar.put(i, Array.get(f.get(obj), i));
                    }
                    js.put(name, ar);
                } else {
                js.put(name, parseObjectToJSONClass(f.get(obj)));
                }
            }
            } catch (IllegalArgumentException e) {
            System.err.println(e.getMessage());
            } catch (IllegalAccessException e) {
            System.err.println(e.getMessage());
            } catch (JSONException e) {
            System.err.println(e.getMessage());
            }
        }
        return js;
    }
}