(此文章是从网络上摘抄)
一.使用 java 接口
-
创建 URL 以及 URLConnection / HttpURLConnection 对象
-
设置连接参数
-
连接到服务器
-
向服务器写数据
-
从服务器读取数据
public class HttpUtils
{private static final int TIMEOUT_IN_MILLIONS = 5000;
public interface CallBack
{
void onRequestComplete(String result);
}/**
-
异步的Get请求
-
@param urlStr
-
@param callBack
*/
public static void doGetAsyn(final String urlStr, final CallBack callBack)
{
new Thread()
{
public void run()
{
try
{
String result = doGet(urlStr);
if (callBack != null)
{
callBack.onRequestComplete(result);
}
} catch (Exception e)
{
e.printStackTrace();
}};
}.start();
}
/**
-
异步的Post请求
-
@param urlStr
-
@param params
-
@param callBack
-
@throws Exception
*/
public static void doPostAsyn(final String urlStr, final String params,
final CallBack callBack) throws Exception
{
new Thread()
{
public void run()
{
try
{
String result = doPost(urlStr, params);
if (callBack != null)
{
callBack.onRequestComplete(result);
}
} catch (Exception e)
{
e.printStackTrace();
}};
}.start();
}
/**
-
Get请求,获得返回数据
-
@param urlStr
-
@return
-
@throws Exception
/
public static String doGet(String urlStr)
{
URL url = null;
HttpURLConnection conn = null;
InputStream is = null;
ByteArrayOutputStream baos = null;
try
{
url = new URL(urlStr);
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);
conn.setRequestMethod(“GET”);
conn.setRequestProperty(“accept”, "/*");
conn.setRequestProperty(“connection”, “Keep-Alive”);
if (conn.getResponseCode() == 200)
{
is = conn.getInputStream();
baos = new ByteArrayOutputStream();
int len = -1;
byte[] buf = new byte[128];while ((len = is.read(buf)) != -1) { baos.write(buf, 0, len); } baos.flush(); return baos.toString(); } else { throw new RuntimeException(" responseCode is not 200 ... "); }
} catch (Exception e)
{
e.printStackTrace();
} finally
{
try
{
if (is != null)
is.close();
} catch (IOException e)
{
}
try
{
if (baos != null)
baos.close();
} catch (IOException e)
{
}
conn.disconnect();
}return null ;
}
/**
-
向指定 URL 发送POST方法的请求
-
@param url
-
发送请求的 URL
-
@param param
-
请求参数,请求参数应该是 name1=value1&name2=value2 的形式。
-
@return 所代表远程资源的响应结果
-
@throws Exception
/
public static String doPost(String url, String param)
{
PrintWriter out = null;
BufferedReader in = null;
String result = “”;
try
{
URL realUrl = new URL(url);
// 打开和URL之间的连接
HttpURLConnection conn = (HttpURLConnection) realUrl
.openConnection();
// 设置通用的请求属性
conn.setRequestProperty(“accept”, "/*");
conn.setRequestProperty(“connection”, “Keep-Alive”);
conn.setRequestMethod(“POST”);
conn.setRequestProperty(“Content-Type”,
“application/x-www-form-urlencoded”);
conn.setRequestProperty(“charset”, “utf-8”);
conn.setUseCaches(false);
// 发送POST请求必须设置如下两行
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setReadTimeout(TIMEOUT_IN_MILLIONS);
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS);if (param != null && !param.trim().equals("")) { // 获取URLConnection对象对应的输出流 out = new PrintWriter(conn.getOutputStream()); // 发送请求参数 out.print(param); // flush输出流的缓冲 out.flush(); } // 定义BufferedReader输入流来读取URL的响应 in = new BufferedReader( new InputStreamReader(conn.getInputStream())); String line; while ((line = in.readLine()) != null) { result += line; }
} catch (Exception e)
{
e.printStackTrace();
}
// 使用finally块来关闭输出流、输入流
finally
{
try
{
if (out != null)
{
out.close();
}
if (in != null)
{
in.close();
}
} catch (IOException ex)
{
ex.printStackTrace();
}
}
return result;
}
}
二.使用 apache 接口
-
-
创建 HttpClient 以及 GetMethod / PostMethod, HttpRequest等对象;
-
设置连接参数;
-
执行 HTTP 操作;
-
处理服务器返回结果.
public class HttpUtil {
public static String get(String uri){
BufferedReader reader = null;
StringBuffer sb = null;
String result = “”;
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet(uri);
try {
//发送请求,得到响应
HttpResponse response = client.execute(request);//请求成功 if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){ reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent())); sb = new StringBuffer(); String line = ""; String NL = System.getProperty("line.separator"); while((line = reader.readLine()) != null){ sb.append(line); } } } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally{ try { if (null != reader){ reader.close(); reader = null; } } catch (IOException e) { e.printStackTrace(); } } if (null != sb){ result = sb.toString(); } return result;
}
/**-
以post方式发送请求,访问web
-
@param uri web地址
-
@return 响应数据
*/
public static String post(String uri,Map< String , String > params){
BufferedReader reader = null;
StringBuffer sb = null;
String result = “”;
HttpClient client = new DefaultHttpClient();
HttpPost request = new HttpPost(uri);List nvps = new ArrayList ();
Set keySet = params.keySet();
for(String key : keySet) {
nvps.add(new BasicNameValuePair(key, params.get(key)));
}
//保存要传递的参数
// List params = new ArrayList();
//添加参数
//params.add(new BasicNameValuePair(“parameter”,“以Post方式发送请求”));try {
//设置字符集
HttpEntity entity = new UrlEncodedFormEntity(nvps,“utf-8”);
//请求对象
request.setEntity(entity);
//发送请求
HttpResponse response = client.execute(request);//请求成功 if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){ System.out.println("post success"); reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent())); sb = new StringBuffer(); String line = ""; String NL = System.getProperty("line.separator"); while((line = reader.readLine()) != null){ sb.append(line); } }
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
finally{
try {
//关闭流
if (null != reader){
reader.close();
reader = null;
}
} catch (IOException e) {
e.printStackTrace();
}
}
if (null != sb){
result = sb.toString();
}
return result;
}
-
}