Android studio 使用httpurlconnection 网络访问中怎样创建 HttpURLConnection 对象

在 Android Studio 中使用 HttpURLConnection 进行网络访问，需要进行如下步骤创建 HttpURLConnection 对象：

1. 创建 URL 对象，指定要访问的 URL。

URL url = new URL("http://www.example.com");

2. 打开连接，并获取 HttpURLConnection 对象。

HttpURLConnection conn = (HttpURLConnection) url.openConnection();

3. 设置请求方法（GET、POST等）。

conn.setRequestMethod("GET");

4. 设置连接超时时间和读取超时时间。

conn.setConnectTimeout(5000);
conn.setReadTimeout(5000);

5. 设置是否允许输入输出。

conn.setDoInput(true);
conn.setDoOutput(true);

6. 添加请求头信息。

conn.setRequestProperty("Content-Type", "application/json");

7. 获取服务器返回的响应码。

int responseCode = conn.getResponseCode();

8. 获取服务器返回的输入流，读取响应数据。

InputStream inputStream = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
StringBuilder response = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
    response.append(line);
}
reader.close();

9. 关闭 HttpURLConnection 连接。

conn.disconnect();

完整代码示例：

try {
    URL url = new URL("http://www.example.com");
    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
    conn.setRequestMethod("GET");
    conn.setConnectTimeout(5000);
    conn.setReadTimeout(5000);
    conn.setDoInput(true);
    conn.setDoOutput(true);
    conn.setRequestProperty("Content-Type", "application/json");

    int responseCode = conn.getResponseCode();

    InputStream inputStream = conn.getInputStream();
    BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
    StringBuilder response = new StringBuilder();
    String line;
    while ((line = reader.readLine()) != null) {
        response.append(line);
    }
    reader.close();

    conn.disconnect();

    // 处理响应数据
    String responseData = response.toString();
    // ...
} catch (Exception e) {
    e.printStackTrace();
}