connection reset error in https request

[zhaoyinchuan]

HttpConfig config = HttpConfig.custom()
.headers(headers)
.url(iamtokenUrl)
.encoding("utf-8")
.client(HCB.custom().sslpv(SSLs.SSLProtocolVersion.TLSv1_2).ssl().build())
.json(JSON.toJSONString(map));
String result = HttpClientUtil.post(config);

ERROR MESSAGE：
com.arronlong.httpclientutil.exception.HttpProcessException: java.net.SocketException: Connection reset
at com.arronlong.httpclientutil.HttpClientUtil.execute(HttpClientUtil.java:478)
at com.arronlong.httpclientutil.HttpClientUtil.send(HttpClientUtil.java:380)
at com.arronlong.httpclientutil.HttpClientUtil.post(HttpClientUtil.java:131)
at com.caacitc.tcdm.business.imoc.domain.service.impl.ImocOrderImpl.getIamToken(ImocOrderImpl.java:68)