How To Convert Json String To Java Model Object

If you already have your java object laid out you should use the ObjectMapper. You could use a HashMap<> and just use readValue() on Json String directly from mapper or even put it in a JsonNode. But you can actually create the Java object conveniently by parsing it directly by using the object.class.

ObjectMapper mapper = new ObjectMapper();
MyObject lib = mapper.readValue(jsonString, MyObject.class);

ObjectMapper: https://fasterxml.github.io/jackson-databind/javadoc/2.7/com/fasterxml/jackson/databind/ObjectMapper.html