How to get all keys of a JSON object using GSON in Java?
A Gson is a library that can be used to parse Java objects to JSON and vice-versa. It can also be used to convert a JSON string to an equivalent Java object. In order to parse java object to JSON or JSON to java object, we need to import com.google.gson package in the Java program.
We can get all the keys of a JSON object in the below example
Example
import java.util.*; import com.google.gson.*;<strong> </strong>import org.json.*; public class GetJSONAllKeysTest { public static void main(String[] args) { String jsonStr = "{\"Raja\":\"Java\", \"Ravi\":\"SAP\", \"Chaitanya\":\"Python\", \"Adithya\":\"Spark\"}"; JsonParser parser = new JsonParser(); JsonElement element = parser.parse(jsonStr); JsonObject obj = element.getAsJsonObject(); Set<Map.Entry<String, JsonElement>> entries = obj.entrySet(); for(Map.Entry<String, JsonElement> entry: entries) { System.out.println(entry.getKey()); } } }
输出
Raja Ravi Chaitanya Adithya
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