从嵌套 JSON 对象中检索键和值的问题

Question

I need help retrieving the keys and values of this nested JSON . It is a JSON object of multiple values wrapped in another JSON object that is finally wrapped in an array. See an example of what I'm talking about

I've used several codes but don't work.

Like

org.json.JSONObject jsonFile = new org.json.JSONObject(_response);
        org.json.JSONObject key = jsonFile.getJSONObject("x_metadata");

test1 = key.getString("wp_GP_ID");

See Image Here:

I'm using the WordPress rest API so I'll be glad if anyone can assist me😪🙏🏾

Answer 1

I would recommend using the Jackson json processor, it's simple and intuitive.

here is a example.

//json string to JsonNode
String data = "{\"x_metadata\": {\"key_1\": \"text1\"," +
        " \"key_2\": true, \"key_3\": 100.0," +
        " \"key_array\": [\"text array 1\", \"text array 2\"]}}";
ObjectMapper mapper = new ObjectMapper();
JsonNode node = mapper.readTree(data);
System.out.println(node);

//get object x_metadata
JsonNode nodeMetadata = node.get("x_metadata");
System.out.println(nodeMetadata);

//get value of a key
String valueKey = nodeMetadata.get("key_1").asText();
System.out.println(valueKey);

//get key type
System.out.println(nodeMetadata.getNodeType());
System.out.println(nodeMetadata.get("key_2").getNodeType());
System.out.println(nodeMetadata.get("key_3").getNodeType());
System.out.println(nodeMetadata.get("key_array").getNodeType());

//get keys
nodeMetadata.fieldNames().forEachRemaining(System.out::println);

pom.xml dependency.

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.13.3</version>
 </dependency>

here more info about Jackson: https://www.baeldung.com/jackson

I hope it helps you.