Java HTTP客户端开发实战案例

原创桃扇骨 2024-09-13 05:30 78阅读 0赞

在Java中，我们可以使用各种HTTP客户端库来处理HTTP请求和响应。以下是一些实战案例：

1. **使用HttpURLConnection**：
   这是最基础的HTTP客户端实现方式。例如发送GET请求获取资源：
```java
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class SimpleHttpClient {
    public static void main(String[] args) {
        String urlStr = "http://example.com/api/data";
        try {
            URL url = new URL(urlStr);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            
            int responseCode = conn.getResponseCode();
            if(responseCode == 200){
                BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream())));

StringBuilder sb = new StringBuilder();
                String line;
                while ((line = br.readLine()) != null) {
                    sb.append(line);
                }
                System.out.println(sb.toString());
            } else {
                System.out.println("Failed to fetch data. Response Code: " + responseCode);
            }
        } catch (Exception e) {
            System.out.println("Error occurred while fetching data.");
            e.printStackTrace();
        }
    }
}
```
2. **使用OkHttp**：
   OkHttp是一个强大的HTTP客户端库，它提供了更高效和异步的请求方式。以下示例：
```java
import okhttp3.*;

public class OkHttpHttpClient {
    public static void main(String[] args) {
        String urlStr = "https://example.com/api/data";
        
        OkHttpClient client = new OkHttpClient();
        Request request = new Request.Builder()
                .url(urlStr)
                .build();

try (Response response = client.newCall(request).execute()) {
            if (response.code() == 200) {
                String responseBody = response.body().string();
                System.out.println(responseBody);
            } else {
                System.out.println("Failed to fetch data. Response Code: " + response.code());
            }
        } catch (Exception e) {
            System.out.println("Error occurred while fetching data.");
            e.printStackTrace();
        }
    }
}
```
以上就是使用HttpURLConnection和OkHttp这两种方式开发Java HTTP客户端的实战案例。