json中的ObjectMapper.readvalue

Question

In object mapper class am getting JsonParseException when i pass parameter as "abc,asd"(for Junit test purpose) . Please clarify why am getting this exception. What value it will accept it for further processing.

ObjectMapper mapper = new ObjectMapper();
List<LinkedHashMap> listM=mapper .readValue("abc,asd",ArrayList.class);
for (Iterator iterator = listM.iterator(); iterator.hasNext();) {
                LinkedHashMap linkedMap = (LinkedHashMap) iterator.next();
syso("linkedMap .get(methodname).get(0)")

Answer 1

You're getting this exception because abc,asd is not a valid JSON. JSON is a Javascript Object that basically has key and value. Example:

{"abc":"abc"}

And can get a List of these:

[{"abc":"abc"}, {"asd":"asd"}]

So, a valid code would be:

ObjectMapper mapper = new ObjectMapper();
List<LinkedHashMap> listM = mapper.readValue("[{\"abc\":\"abc\"}, {\"asd\":\"asd\"}]", ArrayList.class);
    for (Iterator iterator = listM.iterator(); iterator.hasNext();) {
        LinkedHashMap linkedMap = (LinkedHashMap) iterator.next();
        System.out.println(linkedMap);
    }