java http请求和https请求

jar包：

httpclient-4.3.1.jar

http post请求

xml是post的参数流

url就是链接，要以http开头

返回参数是url返给你的

        public static String httpPost(String xml) throws UnsupportedEncodingException {
String jsonStr = null;
//正式
String URL = "";
HttpClient httpClient = new HttpClient();
PostMethod postMethod = new PostMethod(URL.toString());

//设置连接超时    3s
httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(3000);
//设置读取数据超时    3s

try {
List<Header> headers = new ArrayList<Header>();
headers.add(new Header("contentLength", URL.toString().length() + ""));
httpClient.getHostConfiguration().getParams().setParameter("http.default-headers", headers);
postMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler());

RequestEntity requestEntity = new ByteArrayRequestEntity(xml.getBytes("UTF-8"));
postMethod.setRequestEntity(requestEntity);

int statusCode = httpClient.executeMethod(postMethod);
System.err.println("statusCode:" + statusCode);
if (statusCode != HttpStatus.SC_OK) {
} else {
// 解析
byte [] responseBody = postMethod.getResponseBody();
jsonStr = new String(responseBody, "UTF-8");
}
} catch (HttpException e) {
System.out.println("JsonGet Chatroom HttpException:");
e.printStackTrace();
} catch (IOException e) {
System.out.println("JsonGet Chatroom IOException:");
e.printStackTrace();
} catch (Exception e) {
System.out.println("JsonGet Chatroom Exception:");
e.printStackTrace();
} finally {
postMethod.releaseConnection();
}
return jsonStr;
}

get 请求

方法都和post比较像，po出不一样的地方自己对比一下

                HttpClient httpClient = new HttpClient();
GetMethod getMethod = new GetMethod(sb.toString().replace(" ", "%20"));
List<Header> headers = new ArrayList<Header>();
headers.add(new Header("contentLength", sb.toString().length() + ""));
httpClient.getHostConfiguration().getParams().setParameter("http.default-headers", headers);
getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler());

https 请求

先定义一下ssl证书管理器（MyX509TrustManager.java）

import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.X509TrustManager;

public class MyX509TrustManager implements X509TrustManager {

public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
}

public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
}

public X509Certificate[] getAcceptedIssuers() {
return null;
}
}

/**
 * HTTPS数据传输 通过SSL
 * 
 * @param requestUrl需要传输的url
 * @param requestMethod传输方式：GET/POST
 * @param outputStr传输参数
 * @return返回参数
 */
public static String httpRequestXML(String requestUrl, String requestMethod, String outputStr) {  
StringBuffer buffer = new StringBuffer();  
try {  
// 创建SSLContext对象，并使用我们指定的信任管理器初始化  
TrustManager[] tm = { new MyX509TrustManager() };  
SSLContext sslContext = SSLContext.getInstance("SSL", "SunJSSE");  
sslContext.init(null, tm, new java.security.SecureRandom());  
// 从上述SSLContext对象中得到SSLSocketFactory对象  
SSLSocketFactory ssf = sslContext.getSocketFactory();  

URL url = new URL(requestUrl);  
HttpsURLConnection httpUrlConn = (HttpsURLConnection) url.openConnection();  
httpUrlConn.setSSLSocketFactory(ssf);  

httpUrlConn.setDoOutput(true);  
httpUrlConn.setDoInput(true);  
httpUrlConn.setUseCaches(false);  
// 设置请求方式（GET/POST）  
httpUrlConn.setRequestMethod(requestMethod);  

if ("GET".equalsIgnoreCase(requestMethod))  
httpUrlConn.connect();  

// 当有数据需要提交时  
if (null != outputStr) {  
OutputStream outputStream = httpUrlConn.getOutputStream();  
// 注意编码格式，防止中文乱码  
outputStream.write(outputStr.getBytes("UTF-8"));  
outputStream.close();  
}  

// 将返回的输入流转换成字符串  
InputStream inputStream = httpUrlConn.getInputStream();  
InputStreamReader inputStreamReader = new InputStreamReader(inputStream, "UTF-8");  
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);  

String str = null;  
while ((str = bufferedReader.readLine()) != null) {  
buffer.append(str);  
}  
bufferedReader.close();  
inputStreamReader.close();  
// 释放资源  
inputStream.close();  
inputStream = null;  
httpUrlConn.disconnect();  
} catch (ConnectException ce) {  
ce.printStackTrace();
} catch (Exception e) {  
e.printStackTrace();
}  
return buffer.toString();  
}  

调用例子：

public static void main(String[] args) throws Exception {
String URL = "https*****";
String returnXML = "000";

String request = httpRequestXML(URL, "POST",returnXML);

System.out.println(request);

}