在Java中实现HTTP请求（GET、POST）的方法

原创傷城~ 2024-10-09 15:09 42阅读 0赞

在Java中，我们可以使用一些库来发送HTTP请求。这里我将介绍两个常用的库：HttpURLConnection和OkHttp。

1. 使用HttpURLConnection：

```java
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpGetRequest {
    public static void main(String[] args) {
        String urlStr = "http://example.com/api/data"; // Replace with your URL

try {
            URL url = new URL(urlStr);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();

// Set request method
            conn.setRequestMethod("GET");

// Check response code
            int responseCode = conn.getResponseCode();
            System.out.println("Response Code: " + responseCode);

// Read and print response
            BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream())));
            String inputLine;
            StringBuffer content = new StringBuffer();

while ((inputLine = in.readLine()) != null) {
                content.append(inputLine);
            }

in.close();
            System.out.println("Response Content: " + content.toString());

} catch (Exception e) {
            e.printStackTrace();
        }
    }
}
```

2. 使用OkHttp：

```java
import okhttp3.*;

public class HttpGetRequestOkHttp {
    public static void main(String[] args) {
        String urlStr = "http://example.com/api/data"; // Replace with your URL

OkHttpClient client = new OkHttpClient();

Request request = new Request.Builder()
                .url(urlStr)
                .method("GET")
                .build();

try (Response response = client.newCall(request).execute()) {
            System.out.println("Response Code: " + response.code());

if (response.isSuccessful()) {
                String content = response.body().string();
                System.out.println("Response Content: " + content);
            } else {
                System.out.println("Error occurred: " + response.message());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
```

这些示例展示了如何使用Java的HttpURLConnection和OkHttp库来发送GET请求。你可以根据需要替换URL和方法。