How to connect to ChatGPT API with Java?

To connect to ChatGPT API with Java, you would need to create a HttpUrlConnection in your program to call the API.

Here’s a simple example of how to do it:

1. Add the dependency Maven or Gradle:

Maven:
```
org.apache.httpcomponents httpclient 4.5.13

```
Gradle:
```
compile group: ‘org.apache.httpcomponents’, name: ‘httpclient’, version: ’4.5.13‘
```

1. Import necessary libraries:

```
import org.apache.http.HttpHeaders;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
```

1. Make the post request:

```
String apiKey = “YOUR_API_KEY”;
try { CloseableHttpClient client = HttpClients.createDefault(); HttpPost httpPost = new HttpPost(“https://api.openai.com/v1/engines/davinci-codex/completions”);

String json = “{\prompt\“Hello World\”, \max_tokens\”; StringEntity entity = new StringEntity(json); httpPost.setEntity(entity); httpPost.setHeader(HttpHeaders.AUTHORIZATION, “Bearer “ + apiKey); httpPost.setHeader(HttpHeaders.CONTENT_TYPE, “application/json”); closeableHttpResponse response = client.execute(httpPost); System.out.println(EntityUtils.toString(response.getEntity())); client.close(); } catch (Exception e) { e.printStackTrace(); } ```

Replace `“YOUR_API_KEY”` with your actual API key. You may have to replace `“https://api.openai.com/v1/engines/davinci-codex/completions”` with the correct API endpoint for ChatGPT.

Note: The `try … catch` block is necessary to handle exceptions possibly thrown due to issues with network connectivity or other unforeseen circumstances.