Convert JSON from URL to JSONNode

Question

My code is now: ``` import java.net.URL; import java.util.HashMap; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.annotation.*; public class WeatherClient { public static void main (String[] args) { try { final JsonNode node = new ObjectMapper().readTree(new URL("http://api.wunderground.com/api/5bef7a0ecc7f2933/" + "conditions/q/CA/San_Francisco.json")); } catch (Exception exception) { exception.printStackTrace(); } } } ``` and I get: Exception in thread "main" java.lang.NoSuchMethodError: com.fasterxml.jackson.core.JsonFactory.createParser(Ljava/net/URL;)Lcom/fasterxml/jackson/core/JsonParser; at com.fasterxml.jackson.databind.ObjectMapper.readTree(ObjectMapper.java:1792) at WeatherClient.main(WeatherClient.java:10) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.in…

Accepted Answer

I see no reason why you'd need to use a `Map<String, Object>` when Jackson has the almighty `JsonNode`:

```
final JsonNode node = new ObjectMapper().readTree(new URL("yourURLHere");
```

See the javadoc for `JsonNode`. You can navigate your JSON easily, in fact much more easily than with a `Map`. See methods `.get()`, `.path()`, etc etc.

(shameless plug) And if you want to use JSON Pointer to navigate your JSON, you can also do that:

```
final JsonPointer ptr = JsonPointer.of("current_observation", "display_location");
final JsonNode displayLocation = ptr.get(node);
```

Convert JSON from URL to JSONNode

Solution

Problem