JSON

//class1.isAssignableFrom(class2) est vrai si class 1 est parent de class2
    public static String toJson(Object bean) throws IllegalAccessException {
        String json ="";
        if(bean.getClass()== String.class || bean.getClass() == Date.class){
            return "\""+bean+"\"";
        }
        if(Number.class.isAssignableFrom(bean.getClass())){
            return String.valueOf(bean);
        }

        if(Collection.class.isAssignableFrom(bean.getClass()) ){
            json+="[";
            for(Object o:(Collection)bean){
                json+= ","+toJson(o);
            }
            json = json.replaceFirst(",","");
            json+="]";
            return json;
        }
        if(bean.getClass().isArray()){
            json+="[";
            int length = Array.getLength(bean);
            for (int i = 0; i < length; i ++) {
                Object arrayElement = Array.get(bean, i);
                json+= ","+toJson(arrayElement);
            }

            json = json.replaceFirst(",","");
            json+="]";
            return json;
        }
        json += "{" ;
        for(Field f:bean.getClass().getDeclaredFields()){
            f.setAccessible(true);
            json+= ",\""+f.getName()+"\":";
            if(f.getType() == String.class || f.getType() == Date.class) {
                json += "\""+f.get(bean)+"\"";
                continue;
            }
            if(Object.class.isAssignableFrom(f.getType()) ){
                json+= toJson(f.get(bean));
                continue;
            }

            json += f.get(bean);



        }
        json = json.replaceFirst(",","");
        json += "}";



       return json;
    }