public class FastJsonTest {

    public static void main(String[] args) {
        IndexQuery_Number query_number = new IndexQuery_Number();
        IndexQuery_Comparable query_comparable = new IndexQuery_Comparable();
        List<Integer> keys = Arrays.asList(1234);
        query_number.setKeys(keys);
        query_comparable.setKeys(keys);

        try{
            System.out.println("======= query with number =======");
            String json1 = JSON.toJSONString(query_number);
            System.out.println(json1);
            IndexQuery_Number queryNumber = JSON.parseObject(json1, new TypeReference<IndexQuery_Number>(){});
            System.out.println(queryNumber);

            System.out.println("\n======= query with comparable =======");
            String json2 = JSON.toJSONString(query_comparable);
            System.out.println(json2);
            IndexQuery_Comparable queryComparable = JSON.parseObject(json2, new TypeReference<IndexQuery_Comparable>(){});
            System.out.println(queryComparable);

        }catch (Throwable e){
            e.printStackTrace();
        }
    }

    static class IndexQuery_Comparable{
        List<? extends Comparable> keys;

        public List<? extends Comparable> getKeys() {
            return keys;
        }

        public void setKeys(List<? extends Comparable> keys) {
            this.keys = keys;
        }

        @Override
        public String toString() {
            return "IndexQuery{" +
                    "keys=" + keys +
                    '}';
        }
    }

    static class IndexQuery_Number{
        List<? extends Number> keys;

        public List<? extends Number> getKeys() {
            return keys;
        }

        public void setKeys(List<? extends Number> keys) {
            this.keys = keys;
        }

        @Override
        public String toString() {
            return "IndexQuery{" +
                    "keys=" + keys +
                    '}';
        }
    }

}