本篇文章给大家分享的是有关使用java的milo框架访问OPCUA服务的过程是怎样的，小编觉得挺实用的，因此分享给大家学习，希望大家阅读完这篇文章后可以有所收获，话不多说，跟着小编一起来看看吧。
本次采用KEPServerEX5模拟服务端，使用milo开发的程序作为客户端
一、搭建服务端，KEPServerEX5的安装省略掉，下面是配置过程
设置通道、设备、标签
设置访问的用户名和密码
设置通过opc-ua访问的节点
二、使用milo的框架，开发客户端访问opcua服务
在pom文件中追击以下依赖
<!--start milo--><dependency> <groupId>org.eclipse.milo</groupId> <artifactId>sdk-client</artifactId> <version>0.2.4</version></dependency><dependency> <groupId>org.bouncycastle</groupId> <artifactId>bcpkix-jdk15on</artifactId> <version>1.57</version></dependency><dependency> <groupId>org.eclipse.milo</groupId> <artifactId>sdk-server</artifactId> <version>0.2.4</version></dependency><!--end milo-->OPC UA协议对象接口
package com.jndj.platform.common.milo;import org.eclipse.milo.opcua.sdk.client.OpcUaClient;import org.eclipse.milo.opcua.sdk.client.api.identity.AnonymousProvider;import org.eclipse.milo.opcua.sdk.client.api.identity.IdentityProvider;import org.eclipse.milo.opcua.stack.core.security.SecurityPolicy;import org.eclipse.milo.opcua.stack.core.types.structured.EndpointDescription;import java.util.concurrent.CompletableFuture;import java.util.function.Predicate;public interface OpcUAClientService { default String getEndpointUrl() { return "opc.tcp://127.0.0.1:49320"; } default Predicate<EndpointDescription> endpointFilter() { return e -> true; } default SecurityPolicy getSecurityPolicy() { return SecurityPolicy.None; } default IdentityProvider getIdentityProvider() { return new AnonymousProvider(); } void run(OpcUaClient client, CompletableFuture<OpcUaClient> future) throws Exception;}OPC UA协议对象实体类
package com.jndj.platform.common.milo;import com.google.common.collect.ImmutableList;import org.eclipse.milo.opcua.sdk.client.OpcUaClient;import org.eclipse.milo.opcua.stack.core.types.builtin.*;import org.eclipse.milo.opcua.stack.core.types.enumerated.TimestampsToReturn;import org.springframework.stereotype.Service;import java.util.List;import java.util.concurrent.CompletableFuture;@Service("OpcUAClientService")public class OpcUAClientServiceImpl implements OpcUAClientService { @Override public void run(OpcUaClient client, CompletableFuture<OpcUaClient> future) throws Exception { // 同步建立连接 client.connect().get(); // 异步读取数据 readTagData(client).thenAccept(values -> { DataValue nodeId_Tag1 = values.get(0); DataValue nodeId_Tag2 = values.get(1); System.out.println("#########Tag1=" + nodeId_Tag1.getValue().getValue()); System.out.println("#########Tag2=" + nodeId_Tag2.getValue().getValue()); future.complete(client); }); } private CompletableFuture<List<DataValue>> readTagData(OpcUaClient client) { NodeId nodeId_Tag1 = new NodeId(2, "Channel1.Device1.Tag1"); NodeId nodeId_Tag2 = new NodeId(2, "Channel1.Device1.Tag2"); List<NodeId> nodeIds = ImmutableList.of(nodeId_Tag1, nodeId_Tag2); return client.readValues(0.0, TimestampsToReturn.Both, nodeIds); }}OPC UA协议运行对象
package com.jndj.platform.common.milo;import org.eclipse.milo.opcua.sdk.client.OpcUaClient;import org.eclipse.milo.opcua.sdk.client.api.config.OpcUaClientConfig;import org.eclipse.milo.opcua.sdk.client.api.identity.UsernameProvider;import org.eclipse.milo.opcua.stack.client.UaTcpStackClient;import org.eclipse.milo.opcua.stack.core.Stack;import org.eclipse.milo.opcua.stack.core.types.builtin.LocalizedText;import org.eclipse.milo.opcua.stack.core.types.structured.EndpointDescription;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.stereotype.Service;import java.nio.file.Files;import java.nio.file.Path;import java.nio.file.Paths;import java.util.Arrays;import java.util.concurrent.CompletableFuture;import java.util.concurrent.ExecutionException;import java.util.concurrent.TimeUnit;import static org.eclipse.milo.opcua.stack.core.types.builtin.unsigned.Unsigned.uint;@Service("OpcUAClientRunner")public class OpcUAClientRunner { private final Logger logger = LoggerFactory.getLogger(getClass()); private final CompletableFuture<OpcUaClient> future = new CompletableFuture<>(); private final OpcUAClientService opcUAClientService; public OpcUAClientRunner(OpcUAClientService opcUAClientService) { this.opcUAClientService = opcUAClientService; } public void run() { try { // 创建OPC UA客户端 OpcUaClient opcUaClient = createClient(); // future执行完毕后，异步判断状态 future.whenCompleteAsync((c, ex) -> { if (ex != null) { logger.error("连接OPC UA服务错误: {}", ex.getMessage(), ex); } // 关闭OPC UA客户端 try { opcUaClient.disconnect().get(); Stack.releaseSharedResources(); } catch (InterruptedException | ExecutionException e) { logger.error("OPC UA服务关闭错误: {}", e.getMessage(), e); } }); try { // 获取OPC UA服务器的数据 opcUAClientService.run(opcUaClient, future); future.get(5, TimeUnit.SECONDS); } catch (Throwable t) { logger.error("OPC UA客户端运行错误: {}", t.getMessage(), t); future.completeExceptionally(t); } } catch (Throwable t) { logger.error("OPC UA客户端创建错误: {}", t.getMessage(), t); future.completeExceptionally(t); } } private OpcUaClient createClient() throws Exception { Path securityTempDir = Paths.get(System.getProperty("java.io.tmpdir"), "security"); Files.createDirectories(securityTempDir); if (!Files.exists(securityTempDir)) { throw new Exception("不能够创建安全路径: " + securityTempDir); } KeyStoreLoader loader = new KeyStoreLoader().load(securityTempDir); // 获取OPC UA的服务器端节点 EndpointDescription[] endpoints = UaTcpStackClient.getEndpoints(opcUAClientService.getEndpointUrl()).get(); EndpointDescription endpoint = Arrays.stream(endpoints) .filter(e -> e.getEndpointUrl().equals(opcUAClientService.getEndpointUrl())) .findFirst().orElseThrow(() -> new Exception("没有节点返回")); // 设置OPC UA的配置信息 OpcUaClientConfig config = OpcUaClientConfig.builder() .setApplicationName(LocalizedText.english("OPC UA SCREEN")) .setApplicationUri("urn:DATA-TRANSFER:OPC UA SCREEN") .setCertificate(loader.getClientCertificate()) .setKeyPair(loader.getClientKeyPair()) .setEndpoint(endpoint) .setIdentityProvider(new UsernameProvider("Administrator", "123456")) .setRequestTimeout(uint(5000)) .build(); // 创建OPC UA客户端 return new OpcUaClient(config); }}OPC UA访问证书类
package com.jndj.platform.common.milo;import org.eclipse.milo.opcua.sdk.server.util.HostnameUtil;import org.eclipse.milo.opcua.stack.core.util.SelfSignedCertificateBuilder;import org.eclipse.milo.opcua.stack.core.util.SelfSignedCertificateGenerator;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import java.io.InputStream;import java.io.OutputStream;import java.nio.file.Files;import java.nio.file.Path;import java.security.*;import java.security.cert.X509Certificate;import java.util.regex.Pattern;class KeyStoreLoader { private final Logger logger = LoggerFactory.getLogger(getClass()); private static final Pattern IP_ADDR_PATTERN = Pattern.compile( "^(([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.){3}([01]?\\d\\d?|2[0-4]\\d|25[0-5])$"); // 证书别名 private static final String CLIENT_ALIAS = "client-ai"; // 获取私钥的密码 private static final char[] PASSWORD = "password".toCharArray(); // 证书对象 private X509Certificate clientCertificate; // 密钥对对象 private KeyPair clientKeyPair; KeyStoreLoader load(Path baseDir) throws Exception { // 创建一个使用`PKCS12`加密标准的KeyStore。KeyStore在后面将作为读取和生成证书的对象。 KeyStore keyStore = KeyStore.getInstance("PKCS12"); // PKCS12的加密标准的文件后缀是.pfx，其中包含了公钥和私钥。 // 而其他如.der等的格式只包含公钥，私钥在另外的文件中。 Path serverKeyStore = baseDir.resolve("example-client.pfx"); logger.info("Loading KeyStore at {}", serverKeyStore); // 如果文件不存在则创建.pfx证书文件。 if (!Files.exists(serverKeyStore)) { keyStore.load(null, PASSWORD); // 用2048位的RAS算法。`SelfSignedCertificateGenerator`为Milo库的对象。 KeyPair keyPair = SelfSignedCertificateGenerator.generateRsaKeyPair(2048); // `SelfSignedCertificateBuilder`也是Milo库的对象，用来生成证书。 // 中间所设置的证书属性可以自行修改。 SelfSignedCertificateBuilder builder = new SelfSignedCertificateBuilder(keyPair) .setCommonName("Eclipse Milo Example Client") .setOrganization("digitalpetri") .setOrganizationalUnit("dev") .setLocalityName("Folsom") .setStateName("CA") .setCountryCode("US") .setApplicationUri("urn:eclipse:milo:examples:client") .addDnsName("localhost") .addIpAddress("127.0.0.1"); // Get as many hostnames and IP addresses as we can listed in the certificate. for (String hostname : HostnameUtil.getHostnames("0.0.0.0")) { if (IP_ADDR_PATTERN.matcher(hostname).matches()) { builder.addIpAddress(hostname); } else { builder.addDnsName(hostname); } } // 创建证书 X509Certificate certificate = builder.build(); // 设置对应私钥的别名，密码，证书链 keyStore.setKeyEntry(CLIENT_ALIAS, keyPair.getPrivate(), PASSWORD, new X509Certificate[]{certificate}); try (OutputStream out = Files.newOutputStream(serverKeyStore)) { // 保存证书到输出流 keyStore.store(out, PASSWORD); } } else { try (InputStream in = Files.newInputStream(serverKeyStore)) { // 如果文件存在则读取 keyStore.load(in, PASSWORD); } } // 用密码获取对应别名的私钥。 Key serverPrivateKey = keyStore.getKey(CLIENT_ALIAS, PASSWORD); if (serverPrivateKey instanceof PrivateKey) { // 获取对应别名的证书对象。 clientCertificate = (X509Certificate) keyStore.getCertificate(CLIENT_ALIAS); // 获取公钥 PublicKey serverPublicKey = clientCertificate.getPublicKey(); // 创建Keypair对象。 clientKeyPair = new KeyPair(serverPublicKey, (PrivateKey) serverPrivateKey); } return this; } // 返回证书 X509Certificate getClientCertificate() { return clientCertificate; } // 返回密钥对 KeyPair getClientKeyPair() { return clientKeyPair; }}业务service类
package com.jndj.platform.phase2.service.impl;import com.jndj.platform.common.milo.OpcUAClientRunner;import com.jndj.platform.common.milo.OpcUAClientService;import com.jndj.platform.phase2.service.Phase2Service;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;@Service("phase2Service")public class Phase2ServiceImpl implements Phase2Service { @Autowired private OpcUAClientService opcUAClientService; @Override public void searchPhase2ElectricData() { new OpcUAClientRunner(opcUAClientService).run(); }}业务Controller类、定时调度
package com.jndj.platform.phase2.controller;import com.jndj.platform.phase2.service.Phase2Service;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.scheduling.annotation.Scheduled;import org.springframework.stereotype.Controller;import java.text.SimpleDateFormat;import java.util.Date;@Controllerpublic class Phase2Controller { private static final Logger logger = LoggerFactory.getLogger(Phase2Controller.class); private static final SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy:mm:dd HH:mm:ss"); @Autowired private Phase2Service phase2Service; @Scheduled(initialDelay = 30000, fixedRate = 30000) public void searchGasData() { logger.info("####获取二期发电数据（三、四号机组） - 定时任务执行时间："+ dateFormat.format(new Date())); phase2Service.searchPhase2ElectricData(); }}运行结果、定时获取到opcua服务中的数据
OK，以上是所有的源代码，大家的问题基本能够解决。
以上就是使用java的milo框架访问OPCUA服务的过程是怎样的，小编相信有部分知识点可能是我们日常工作会见到或用到的。希望你能通过这篇文章学到更多知识。更多详情敬请关注编程网行业资讯频道。
