unable to find valid certification path to requested target

调用https接口时出现该异常，
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

 
原因是可以看上图，因为本地没有目标服务器证书导致。解决此方法的两种方案，1.在运行java环境安装对方服务器证书，可使用keytool -printcert -rfc -sslserver ip:port 后保存为cer格式。2.在http建立连接时跳过证书验证
CloseableHttpClient httpClient = getScontractHttpClient();

public static CloseableHttpClient getScontractHttpClient() {
SSLContext sslContext = null;
try {
sslContext = SSLContexts.custom().loadTrustMaterial(null, new TrustStrategy() {
@Override
public boolean isTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
return true;
}
}).build();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (KeyManagementException e) {
e.printStackTrace();
} catch (KeyStoreException e) {
e.printStackTrace();
}
//创建httpClient
return HttpClients.custom().setSSLContext(sslContext).
setSSLHostnameVerifier(new NoopHostnameVerifier()).build();

}