java前台接口调用,Java 接口调用

/**

* 向指定 URL 发送POST方法的请求

* @param url 发送请求的 URL

* @param params 请求的参数集合

* @return 远程资源的响应结果

*/

private String sendPost(String url, Map params) {

OutputStreamWriter out = null;

BufferedReader in = null;

StringBuilder result = new StringBuilder();

try {

URL realUrl = new URL(url);

HttpURLConnection conn =(HttpURLConnection) realUrl.openConnection();

// 发送POST请求必须设置如下两行

conn.setDoOutput(true);

conn.setDoInput(true);

// POST方法

conn.setRequestMethod("POST");

// 设置通用的请求属性

conn.setRequestProperty("accept", "*/*");

conn.setRequestProperty("connection", "Keep-Alive");

conn.setRequestProperty("user-agent",

"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");

conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");

conn.connect();

// 获取URLConnection对象对应的输出流

out = new OutputStreamWriter(conn.getOutputStream(), "UTF-8");

// 发送请求参数

if (params != null) {

StringBuilder param = new StringBuilder();

for (Map.Entry entry : params.entrySet()) {

if(param.length()>0){

param.append("&");

}

param.append(entry.getKey());

param.append("=");

param.append(entry.getValue());

}

out.write(param.toString());

}

// 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(), "UTF-8"));

String line;

while ((line = in.readLine()) != null) {

result.append(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.toString();

}