Check out example codes for "how to read file in java jacakson". It will help you in understanding the concepts better.

Code Example 1

try {
    // create object mapper instance
    ObjectMapper mapper = new ObjectMapper();

    // convert JSON file to map
    Map<?, ?> map = mapper.readValue(Paths.get("book.json").toFile(), Map.class);

    // print map entries
    for (Map.Entry<?, ?> entry : map.entrySet()) {
        System.out.println(entry.getKey() + "=" + entry.getValue());
    }

} catch (Exception ex) {
    ex.printStackTrace();
}

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