Java: Data Science Made Easy

Using the JSON tree API

The second approach is to use the tree model. An ObjectMapper instance is used to create a JsonNode instance using the Persons.json file. The fieldNames method returns Iterator allowing us to process each element of the file.

try {     ObjectMapper mapper = new ObjectMapper();     JsonNode node = mapper.readTree(new File("Persons.json"));     Iterator<String> fieldNames = node.fieldNames();     while (fieldNames.hasNext()) {         ...         fieldNames.next();     } } catch (IOException ex) {     // Handle exceptions } 

Since the JSON file contains a persons field, we will obtain a JsonNode instance representing the field and then iterate over each of its elements.

JsonNode personsNode = node.get("persons"); Iterator<JsonNode> elements = personsNode.iterator(); ...