post、get请求一般出现在前端调用后端接口的时候,现在如果希望java代码去调用controller接口,比如在job定时器中,达到某一条件需要返回给前端一条提示消息(如订单30分钟内未付款,已被自动取消),而前端只能调controler接口,所以这时可以用job去调controller接口,在这个controller接口里面返回信息给前端。
* @param url:请求url
* @param content: 请求体(参数)
* @return errorStr:错误信息;status:状态码,response:返回数据
*/
public Map<String, Object> request(String url, String content) {
Map<String, Object> result = new HashMap<String, Object>();
String errorStr = "";
String status = "";
String response = "";
PrintWriter out = null;
BufferedReader in = null;
try {
URL realUrl = new URL(url);
// 打开和URL之间的连接
URLConnection conn = realUrl.openConnection();
HttpURLConnection httpUrlConnection = (HttpURLConnection) conn;
// 设置请求属性
httpUrlConnection.setRequestProperty("Content-Type", "application/json");
httpUrlConnection.setRequestProperty("x-adviewrtb-version", "2.1");
// 发送POST请求必须设置如下两行
httpUrlConnection.setDoOutput(true);
httpUrlConnection.setDoInput(true);
// 获取URLConnection对象对应的输出流
out = new PrintWriter(httpUrlConnection.getOutputStream());
// 发送请求参数
out.write(content);
// flush输出流的缓冲
out.flush();
httpUrlConnection.connect();
// 定义BufferedReader输入流来读取URL的响应
in = new BufferedReader(new InputStreamReader(httpUrlConnection.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
response += line;
}
status = new Integer(httpUrlConnection.getResponseCode()).toString();
} catch (Exception e) {
System.out.println("发送 POST 请求出现异常!" + e);
errorStr = e.getMessage();
}
// 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 (Exception ex) {
ex.printStackTrace();
}
}
result.put("errorStr", errorStr);
result.put("response", response);
result.put("status", status);
return result;
}