java后台模拟页面post请求

java后台模拟页面post请求

/**
  *targetUrl:请求url
  *urlParam:需要封装进url的参数
  *body：需要传递的参数
  *type：请求格式类型：1.json;2.form-data;3.x-www-form-urlencoded
  */
  private String httpPOST(String targetUrl,JSONObject urlParamJosn,JSONObject body,int type){
    try{
      CloseableHttpClient httpClient = HttpClients.createDefault();  
      StringBuilder param=new StringBuilder("");
      for (String key:urlParamJosn.keySet()){
        param.append(key + "=" + URLEncoder.encode((String) urlParamJosn.get(key), "UTF-8") + "&");
      }
      String targetUrl = targetUrl+(param.indexOf("&") > 0?param.deleteCharAt(param.lastIndexOf("&")).toString():"");
      HttpPost httpPost = new HttpPost(targetUrl);     
      
      if(body != null && !body.isEmpty()){
        if (type == 1) {
          StringEntity entity=new StringEntity(body.toJSONString(), ContentType.APPLICATION_JSON);
          httpPost.setEntity(entity);
        }else if (type == 2) {
          MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create();        
          for (String key:body.keySet()){
            multipartEntityBuilder.addPart(key, new StringBody(body.get(key).toString(), ContentType.create("text/plain", Consts.UTF_8)));
          }
          httpPost.setEntity(multipartEntityBuilder.build());
        }else if (type == 3) {
          List params = new ArrayList();      
          for (String key:body.keySet()){
            params.add(new BasicNameValuePair(key, body.get(key).toString()));
          }
          HttpEntity reqEntity = new UrlEncodedFormEntity(params);
          System.out.println("the request body is:"+EntityUtils.toString(reqEntity));
          httpPost.setEntity(reqEntity);
          httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");
        }   
      }       
      HttpResponse result = httpClient.execute(httpPost);          
      System.out.println(result.getStatusLine().getStatusCode());
      if (302 == result.getStatusLine().getStatusCode()) {
        System.out.println(result.getFirstHeader("location"));
        return result.getFirstHeader("location").getValue();
      }
      HttpEntity entity = result.getEntity();
      return EntityUtils.toString(entity, "UTF-8");
      }catch(Exception e){
          e.printStackTrace();
      }
    return null;
  }

• json类型用StringEntity实例。 form-data类型用multipartEntity 实例。
  x-www-form-urlencoded类型用UrlEncodedFormEntity实例。