1.使用HttpURLConnection访问网络资源
<span style="font-size:14px;">private String httpUrlForResult(URL url) { String resultStr = ""; HttpURLConnection httpConnection = null; InputStream in = null; try { httpConnection = (HttpURLConnection) url.openConnection(); httpConnection.setConnectTimeout(1000);// 设置超时时间 httpConnection.setReadTimeout(10000); // 设置请求方式,表示设置为get // httpConnection.setRequestMethod("GET"); // 设置为post方式 httpConnection.setDoInput(true); httpConnection.setDoOutput(true); httpConnection.setUseCaches(false);// 忽略缓存 httpConnection.setRequestMethod("POST"); httpConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); // 输出键值对 httpConnection.setRequestProperty("Connection", "Keep-Alive"); // 维持长连接 httpConnection.setRequestProperty("Charset", "utf-8"); httpConnection .setRequestProperty( "User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 5.2) AppleWebKit/525.13 (KHTML, like Gecko) Chrome/0.2.149.27 Safari/525.13"); httpConnection.setRequestProperty("Accept", "*/*"); httpConnection.setRequestProperty("Accept-Encoding", "identity"); OutputStream out = httpConnection.getOutputStream(); out.write(1);// post请求的数据，即写出的数据,这儿可根据自己的需求改 out.flush(); out.close(); in = httpConnection.getInputStream(); BufferedReader reader = new BufferedReader( new InputStreamReader(in)); int responseContent = httpConnection.getContentLength(); StringBuilder sb = new StringBuilder(); if (responseContent != 0) { int responseCode = httpConnection.getResponseCode(); if (responseCode == HttpURLConnection.HTTP_OK) { String line = null; while ((line = reader.readLine()) != null) { sb.append(line); } } } resultStr = sb.toString(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally { if (httpConnection != null) { httpConnection.disconnect(); } if (in != null) { try { in.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return resultStr; }</span>2.HttpClient访问网络资源（1）get请求
private String connServerForResult(String url) { String strResult = ""; BufferedReader reader = null; HttpGet httprequest = new HttpGet(url); HttpClient httpclient = new DefaultHttpClient(); try { HttpResponse httpresponse = httpclient.execute(httprequest); reader = new BufferedReader(new InputStreamReader(httpresponse .getEntity().getContent())); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line); } strResult = sb.toString(); return strResult; } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return strResult; }（2）post请求（只做了部分判断）
public String connServerForResultP(String url) { String result = null; BufferedReader reader = null; try { HttpClient client = new DefaultHttpClient(); HttpPost request = new HttpPost(url); List<NameValuePair> postParameters = new ArrayList<NameValuePair>(); postParameters.add(new BasicNameValuePair("name", "zhangyabin")); postParameters.add(new BasicNameValuePair("password", "99999999")); UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity( postParameters); request.setEntity(formEntity); HttpResponse response = client.execute(request); reader = new BufferedReader(new InputStreamReader(response .getEntity().getContent())); StringBuffer strBuffer = new StringBuffer(""); String line = null; while ((line = reader.readLine()) != null) { strBuffer.append(line); } result = strBuffer.toString(); } catch (Exception e) { e.printStackTrace(); } finally { if (reader != null) { try { reader.close(); reader = null; } catch (IOException e) { e.printStackTrace(); } } } return result; }get和post请求的区别（资料查询所得）
1.get是从服务器上获取数据，post是向服务器传送数据。
2.get是把参数数据队列加到提交表单的ACTION属性所指的URL中，值和表单内各个字段一一对应，在URL中可以看到。post是通过HTTP post机制，
将表单内各个字段与其内容放置在HTML HEADER内一起传送到ACTION属性所指的URL地址。用户看不到这个过程。如果不指定Method，则默认 为GET请求，Form中提交的数据将会附加在url之后，以?分开与url分开。
3.HTTP协议没有对传输的数据大小进行限制，HTTP协议规范也没有对URL长度进行限制，开发中存在的限制主要 是：GET:特定浏览器和服务器对URL长度有限
制，其限制取决于操作系 统的支持。POST:由于不是通过URL传值，理论上数据不受限。但实际各个WEB服务器会规定对post提交数据大小进行限制，
Apache、IIS6 都有各自的配置。
版权声明：本文为博主原创文章，未经博主允许不得转载。