我是opc ua的新手，不是java的Maven。在java中设置客户机时，我在证书处理方面遇到了问题。我想通过basic 256，signandencrypt连接到服务器。据我所知，在这个安全阶段，由客户机创建或加载的证书被发送到服务器，在那里它必须被接受。然后服务器将证书发送回客户机，然后客户机需要接受该证书。如果我错了，请纠正我。
在客户端创建/加载证书并将其发送到服务器已经可以正常工作（请参阅下面的代码），然后我可以在服务器端手动接受它。但在那之后，我陷入了困境：如何在代码中看到这个证书验证，如何找到服务器证书，更不用说接受它了？在实现过程中，我使用opc-ua的sampleconsoleclient进行了一些定位。但与此相反，我不使用任何用户输入。
这是我目前的一些代码。
初始化：

try {
        client = new UaClient(serverUri);
    } catch (final URISyntaxException e) {
        throw new InitializationException("The server uri has an invalid syntax.", e);
    }
    try {
        client.setApplicationIdentity(createApplicationIdentity());
    } catch (final SecureIdentityException e) {
        throw new InitializationException(
                "Application Identity could not be created due to a Security Identity Exception.", e);
    } catch (final IOException e) {
        throw new InitializationException("Application Identity could not be created due to an IO Exception.",
                e);
    }

createapplicationidentity（）：

final ApplicationDescription appDescription = new ApplicationDescription();
    appDescription.setApplicationName(new LocalizedText(APPLICATION_NAME, Locale.ENGLISH));
    appDescription.setApplicationUri(APPLICATION_URI);
    appDescription.setProductUri(PRODUCT_URI);
    appDescription.setApplicationType(ApplicationType.Client);

    // Setting security features
    client.setSecurityMode(SecurityMode.BASIC256_SIGN_ENCRYPT);
    client.setCertificateValidator(validator);
    validator.setValidationListener(myValidationListener); //myValidationListener is similar to most lines in MyCertificateValidationListener in the opc ua samples
    final File privatePath = new File(validator.getBaseDir(), "private");
    final KeyPair issuerCertificate = null;
    final int[] keySizes = null;
    final ApplicationIdentity identity = ApplicationIdentity.loadOrCreateCertificate(appDescription,
            "Sample Organisation", "opcua", privatePath, issuerCertificate, keySizes, true);
    identity.setApplicationDescription(appDescription);
    return identity;

在初始化之后，我尝试这样连接（通过注解，我想象连接可以正常工作）：

final String securityPolicy = client.getEndpoint() == null
            ? client.getSecurityMode().getSecurityPolicy().getPolicyUri()
                    : client.getEndpoint().getSecurityPolicyUri();

            client.setSessionName(String.format("%s@%s/Session%d", APPLICATION_NAME,
                    ApplicationIdentity.getActualHostNameWithoutDomain(), ++sessionCount));
            try {
                //Idea: catch the server certificate and accept it. Only if that was possible: connect
                client.connect();
            } catch (final ServiceException e) {
                e.printStackTrace();
            }
            client.setKeepSubscriptions(false);
            // After that resolving namespace index (works fine)
            }

以及抛出的错误：

WARN  (?:?): /<IPofServer> Error org.opcfoundation.ua.common.ServiceResultException: Bad_SecurityChecksFailed
(0x80130000) "An error occurred verifying security." at
org.opcfoundation.ua.transport.tcp.io.TcpConnection$ReadThread.run(Unknown Source)
com.prosysopc.ua.client.ConnectException: Failed to create secure channel to server: : opc.tcp://<IPofServer>
[http://opcfoundation.org/UA/SecurityPolicy#Basic256,SignAndEncrypt]
ServiceResult=Bad_SecurityChecksFailed (0x80130000) "An error occurred verifying security."
at com.prosysopc.ua.client.UaClient.n(Unknown Source)
at com.prosysopc.ua.client.UaClient.connect(Unknown Source)
at *lineOfCode*
Caused by: org.opcfoundation.ua.common.ServiceResultException:
Bad_SecurityChecksFailed (0x80130000) "An error occurred verifying security."
at org.opcfoundation.ua.transport.tcp.io.TcpConnection$ReadThread.run(Unknown Source)

代码行是 client.connect() .
提前谢谢你的帮助！！