如何在android上使用代理进行HTTP连接？

System.setProperty("http.proxyHost", "代理服务器地址");
System.setProperty("http.proxyPort", "代理服务器端口");

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

HttpClient httpClient = new DefaultHttpClient();
HttpHost proxy = new HttpHost("代理服务器地址", 代理服务器端口);
httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
HttpGet httpGet = new HttpGet("http://www.example.com");
HttpResponse response = httpClient.execute(httpGet);

// 使用URLConnection发送GET请求
InputStream inputStream = connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
StringBuilder response = new StringBuilder();
while ((line = reader.readLine()) != null) {
    response.append(line);
}
reader.close();

// 使用HttpClient发送GET请求
HttpResponse response = httpClient.execute(httpGet);
HttpEntity entity = response.getEntity();
String result = EntityUtils.toString(entity);