javahttp连接

‘壹’ java如何使用http方式调用第三方接口最好有代码~谢谢

星号是IP地址和端口号
public class HttpUtil {
private final static Log log = LogFactory.getLog(HttpUtil.class);
public static String doHttpOutput(String outputStr,String method) throws Exception {
Map map = new HashMap();
String URL = "http://****/interface/http.php" ;
String result = "";
InputStream is = null;
int len = 0;
int tmp = 0;

OutputStream output = null;
BufferedOutputStream objOutput = null;
String charSet = "gbk";
System.out.println("URL of fpcy request");
System.out.println("=============================");
System.out.println(URL);
System.out.println("=============================");
HttpURLConnection con = getConnection(URL);
try {
output = con.getOutputStream();
objOutput = new BufferedOutputStream(output);
objOutput.write(outputStr.getBytes(charSet));
objOutput.flush();
output.close();
objOutput.close();
int responseCode = con.getResponseCode();
if (responseCode == 200) {
is = con.getInputStream();
int dataLen = is.available();
int retry = 5;
while (dataLen == 0 && retry > 0) {
try {
Thread.sleep(100);
} catch (InterruptedException e) {
}
dataLen = is.available();
retry--;
log.info("未获取到任何数据，尝试重试，当前剩余次数" + retry);
}
log.info("获取到报文单位数据长度:" + dataLen);
byte[] bytes = new byte[dataLen];
while ((tmp = is.read()) != -1) {
bytes[len++] = (byte) tmp;
if (len == dataLen) {
dataLen = bytes.length + dataLen;
byte[] newbytes = new byte[dataLen];
for (int i = 0; i < bytes.length; i++) {
newbytes[i] = bytes[i];
}
bytes = newbytes;
}
}
result = new String(bytes, 0, len, charSet);
} else {
String responseMsg = "调用接口失败,返回错误信息:" + con.getResponseMessage() + "(" + responseCode + ")";
System.out.println(responseMsg);
throw new Exception(responseMsg);
}
} catch (IOException e2) {
log.error(e2.getMessage(), e2);
throw new Exception("接口连接超时！,请检查网络");
}
con.disconnect();
System.out.println("=============================");
System.out.println("Contents of fpcy response");
System.out.println("=============================");
System.out.println(result);
Thread.sleep(1000);
return result;
}
private static HttpURLConnection getConnection(String URL) throws Exception {
Map map = new HashMap();
int rTimeout = 15000;
int cTimeout = 15000;
String method = "";
method = "POST";
boolean useCache = false;
useCache = false;
HttpURLConnection con = null;
try {
con = (HttpURLConnection) new URL(URL).openConnection();
} catch (IOException e) {
log.error(e.getMessage(), e);
throw new Exception("URL不合法！");
}
try {
con.setRequestMethod(method);
} catch (ProtocolException e) {
log.error(e.getMessage(), e);
throw new Exception("通信协议不合法！");
}
con.setConnectTimeout(cTimeout);
con.setReadTimeout(rTimeout);
con.setUseCaches(useCache);
con.setDoInput(true);
con.setDoOutput(true);
log.info("当前连接信息: URL:" + URL + "," + "Method:" + method
+ ",ReadTimeout:" + rTimeout + ",ConnectTimeOut:" + cTimeout
+ ",UseCaches:" + useCache);
return con;
}

public static void main(String[] args) throws Exception {
String xml="<?xml version=\"1.0\" encoding=\"GBK\" ?><document><txcode>101</txcode><netnumber>100001</netnumber>.........</document>";

response=HttpUtil.doHttpOutput(xml, "post");
JSONObject json= JSONObject.parseObject(response);
String retcode=json.getString("retcode");
调用这个类就能获得返回的参数。。over.

}

}
}

‘贰’ 如何实现java http长连接推送数据

Feign在默认情况下使用的是JDK原生的URLConnection发送HTTP请求，没有连接池，但是对每个地址会保持一个长连接，即利用HTTP的persistence connection 。我们可以用Apache的HTTP Client替换Feign原始的http client, 从而获取连接池、超时时间等与性能息息相关的控制能力。Spring Cloud从Brixtion.SR5版本开始支持这种替换，首先在项目中声明Apache HTTP Client和feign-httpclient依赖

‘叁’ java中怎么调用http接口

方法：只要New一个Map，然后把要传递的参数以键值对的形式存入Map即可。
private void Example() {
String url =地址;
Map<String, String> param = new HashMap<String, String>();
p.put("ParamName", "ParamValue");
String html = this.visitURL(url, param);
}