java 发送http和https请求

HTTP请求：
如果需要Json格式的自己转下，度娘上N种姿势…

//处理http请求  requestUrl为请求地址  requestMethod请求方式，值为"GET"或"POST"      public static String httpRequest(String requestUrl,String requestMethod,String outputStr){          StringBuffer buffer=null;          try{          URL url=new URL(requestUrl);          HttpURLConnection conn=(HttpURLConnection)url.openConnection();          conn.setDoOutput(true);          conn.setDoInput(true);          conn.setRequestMethod(requestMethod);          conn.connect();          //往服务器端写内容 也就是发起http请求需要带的参数          if(null!=outputStr){              OutputStream os=conn.getOutputStream();              os.write(outputStr.getBytes("utf-8"));              os.close();          }          //读取服务器端返回的内容          InputStream is=conn.getInputStream();          InputStreamReader isr=new InputStreamReader(is,"utf-8");          BufferedReader br=new BufferedReader(isr);          buffer=new StringBuffer();          String line=null;          while((line=br.readLine())!=null){              buffer.append(line);          }          }catch(Exception e){              e.printStackTrace();          }          return buffer.toString();      }  

HTTPS请求：
1、https和http的区别我这里就不介绍了，在java
中访问https链接的话需要有相应的SSL证书，如果没有就无法访问（使用http访问https会返回403），所以我们要先自定义一个信任管理器。实现java自带的X509TrustManger接口，代码：

import java.security.cert.CertificateException;  import java.security.cert.X509Certificate;  import javax.net.ssl.X509TrustManager;  public class MyX509TrustManager implements X509TrustManager {      @Override      public void checkClientTrusted(X509Certificate[] chain, String authType)              throws CertificateException {          // TODO Auto-generated method stub      }      @Override      public void checkServerTrusted(X509Certificate[] chain, String authType)              throws CertificateException {          // TODO Auto-generated method stub      }      @Override      public X509Certificate[] getAcceptedIssuers() {          // TODO Auto-generated method stub          return null;      } }  

2、然后我们就可以使用https请求了：

/*  * 处理https GET/POST请求  * 请求地址、请求方法、参数  * */  public static String httpsRequest(String requestUrl,String requestMethod,String outputStr){      StringBuffer buffer=null;      try{      //创建SSLContext      SSLContext sslContext=SSLContext.getInstance("SSL");      TrustManager[] tm={new MyX509TrustManager()};      //初始化      sslContext.init(null, tm, new java.security.SecureRandom());;      //获取SSLSocketFactory对象      SSLSocketFactory ssf=sslContext.getSocketFactory();      URL url=new URL(requestUrl);      HttpsURLConnection conn=(HttpsURLConnection)url.openConnection();      conn.setDoOutput(true);      conn.setDoInput(true);      conn.setUseCaches(false);      conn.setRequestMethod(requestMethod);      //设置当前实例使用的SSLSoctetFactory      conn.setSSLSocketFactory(ssf);      conn.connect();      //往服务器端写内容      if(null!=outputStr){          OutputStream os=conn.getOutputStream();          os.write(outputStr.getBytes("utf-8"));          os.close();      }      //读取服务器端返回的内容      InputStream is=conn.getInputStream();      InputStreamReader isr=new InputStreamReader(is,"utf-8");      BufferedReader br=new BufferedReader(isr);      buffer=new StringBuffer();      String line=null;      while((line=br.readLine())!=null){          buffer.append(line);      }      }catch(Exception e){          e.printStackTrace();      }      return buffer.toString();  }  

参考自 http://blog.csdn.net/guozili1/article/details/53995121