2024-09-06

Spring Cloud Stream 整合 RocketMQ 的基本步骤如下:

  1. 在项目的pom.xml中添加Spring Cloud Stream和RocketMQ Binder的依赖:



<dependencies>
    <!-- Spring Cloud Stream -->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-stream-rocketmq</artifactId>
    </dependency>
    <!-- 其他依赖 -->
</dependencies>
  1. 在application.yml或application.properties中配置RocketMQ的连接信息:



spring:
  cloud:
    stream:
      rocketmq:
        binder:
          namesrv-addr: 127.0.0.1:9876 # RocketMQ NameServer地址
      bindings:
        output:
          destination: test-topic # 指定发送到的topic
          content-type: text/plain # 设置消息类型
        input:
          destination: test-topic # 指定订阅的topic
          content-type: text/plain # 设置消息类型
          group: test-group # 设置消费组
  1. 创建发送和接收消息的服务类:



@EnableBinding(value = {Processor.class})
public class RocketMQService {
 
    @Autowired
    private MessageChannel output;
 
    public void send(String content) {
        output.send(MessageBuilder.withPayload(content).build());
    }
 
    @StreamListener(Processor.INPUT)
    public void receive(String payload) {
        System.out.println("Received: " + payload);
    }
}

在上述代码中,@EnableBinding(Processor.class)注解启用了Spring Cloud Stream的Processor绑定,这允许我们发送和接收消息。send方法用于发送消息,receive方法用@StreamListener注解标记,以接收消息。

确保RocketMQ的服务器正在运行并可以正常访问,然后就可以通过调用send方法发送消息,并在接收端打印出接收到的消息内容。

2024-09-06

在Spring Boot整合Redis多数据源时,通常需要定义多个RedisTemplate实例,每个实例连接不同的Redis数据库。以下是一个简化的例子,展示如何配置和使用两个Redis数据源。




@Configuration
public class RedisConfig {
 
    @Bean
    public LettuceConnectionFactory redis1ConnectionFactory() {
        return new LettuceConnectionFactory(new RedisStandaloneConfiguration("host1", 6379));
    }
 
    @Bean
    public LettuceConnectionFactory redis2ConnectionFactory() {
        return new LettuceConnectionFactory(new RedisStandaloneConfiguration("host2", 6379));
    }
 
    @Bean
    public RedisTemplate<String, Object> redis1Template() {
        RedisTemplate<String, Object> template = new RedisTemplate<>();
        template.setConnectionFactory(redis1ConnectionFactory());
        return template;
    }
 
    @Bean
    public RedisTemplate<String, Object> redis2Template() {
        RedisTemplate<String, Object> template = new RedisTemplate<>();
        template.setConnectionFactory(redis2ConnectionFactory());
        return template;
    }
}

接下来,可以创建一个RedisUtil类来封装对这些RedisTemplate的操作:




@Component
public class RedisUtil {
 
    @Autowired
    @Qualifier("redis1Template")
    private RedisTemplate<String, Object> redis1Template;
 
    @Autowired
    @Qualifier("redis2Template")
    private RedisTemplate<String, Object> redis2Template;
 
    public void setValueToRedis1(String key, Object value) {
        redis1Template.opsForValue().set(key, value);
    }
 
    public Object getValueFromRedis1(String key) {
        return redis1Template.opsForValue().get(key);
    }
 
    public void setValueToRedis2(String key, Object value) {
        redis2Template.opsForValue().set(key, value);
    }
 
    public Object getValueFromRedis2(String key) {
        return redis2Template.opsForValue().get(key);
    }
}

在这个例子中,我们定义了两个RedisTemplate实例,通过@Qualifier注解指定注入哪一个实例。RedisUtil类提供了简单的设置和获取值的方法,分别操作两个不同的Redis数据库。

2024-09-06

以下是一个简化的示例,展示了如何在Spring Boot应用中对接支付宝完整的扫码支付流程:




@Configuration
public class AlipayConfig {
    @Value("${alipay.appId}")
    private String appId;
 
    @Value("${alipay.privateKey}")
    private String privateKey;
 
    @Value("${alipay.publicKey}")
    private String publicKey;
 
    @Value("${alipay.serverUrl}")
    private String serverUrl;
 
    @Value("${alipay.domain}")
    private String domain;
 
    // 提供获取配置属性的方法
    public String getAppId() {
        return appId;
    }
 
    // ... 其他配置属性的获取方法
}
 
@Service
public class AlipayService {
    @Autowired
    private AlipayConfig alipayConfig;
 
    public String startPay(String orderId, String totalAmount) throws AlipayApiException {
        AlipayTradePrecreateRequest request = new AlipayTradePrecreateRequest();
        // 设置商户订单信息
        JSONObject bizContent = new JSONObject();
        bizContent.put("out_trade_no", orderId);
        bizContent.put("total_amount", totalAmount);
        bizContent.put("subject", "商品标题");
        // ... 设置其他必要的参数
        request.setBizContent(bizContent.toString());
        // 使用SDK执行请求
        AlipayTradePrecreateResponse response = alipayClient.execute(request);
        if(response.isSuccess()){
            return response.getQrCode(); // 返回二维码图片的地址
        } else {
            // 处理错误
        }
    }
 
    // ... 其他支付相关的方法
}
 
@RestController
public class AlipayController {
    @Autowired
    private AlipayService alipayService;
 
    @GetMapping("/pay")
    public String startPay(@RequestParam("orderId") String orderId,
                           @RequestParam("totalAmount") String totalAmount) {
        try {
            return alipayService.startPay(orderId, totalAmount);
        } catch (AlipayApiException e) {
            // 异常处理
        }
    }
 
    // ... 其他接口方法
}

以上代码提供了一个简化的示例,展示了如何在Spring Boot应用中集成支付宝支付SDK,并实现扫码支付的基本流程。在实际应用中,你需要处理更多的细节,例如异常处理、安全性考虑(如参数签名验证)、日志记录、事务管理等。

2024-09-06

在Spring Boot中,可以通过以下四种方式注册Servlet:

  1. 继承SpringBootServletInitializer类
  2. 使用ServletRegistrationBean注册
  3. 使用ServletComponentRegister注册
  4. 使用@WebServlet注解注册

下面是这四种方式的示例代码:

  1. 继承SpringBootServletInitializer类



public class MyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.getWriter().write("Hello, world");
    }
}
 
public class ServletInitializer extends SpringBootServletInitializer {
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(ServletInitializer.class);
    }
 
    @Bean
    public ServletRegistrationBean myServlet() {
        return new ServletRegistrationBean(new MyServlet(), "/myServlet");
    }
}
  1. 使用ServletRegistrationBean注册



public class MyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.getWriter().write("Hello, world");
    }
}
 
@Configuration
public class ServletConfig {
    @Bean
    public ServletRegistrationBean myServlet() {
        return new ServletRegistrationBean(new MyServlet(), "/myServlet");
    }
}
  1. 使用@WebServlet注解注册



@WebServlet(name = "myServlet", urlPatterns = "/myServlet")
public class MyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.getWriter().write("Hello, world");
    }
}
  1. 使用ServletComponentRegister注册



@WebServlet(name = "myServlet", urlPatterns = "/myServlet")
public class MyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.getWriter().write("Hello, world");
    }
}
 
@Configuration
public class ServletConfig implements WebServletRegistry {
    @Override
    public void registerServlet(ServletRegistrationBean servletRegistrationBean) {
        servletRegistrationBean.setServlet(new MyServlet());
        servletRegistrationBean.addUrlMappings("/myServlet");
    }
}

以上四种方式均可以在Spring Boot应用中注册Servlet,具体使用哪一种取决于具体的应用场景和需求。

2024-09-06

由于原始代码较为复杂且涉及到火车票订票的具体业务逻辑,我们将提供核心的Spring Boot应用配置和服务层的简化示例。




// 火车票服务接口
public interface TicketService {
    Order queryOrder(String orderId);
    boolean isTicketLeft(String trainNumber, String from, String to);
    Order purchaseTicket(String trainNumber, String from, String to);
}
 
// 火车票服务实现
@Service
public class TicketServiceImpl implements TicketService {
 
    @Autowired
    private OrderRepository orderRepository;
 
    @Autowired
    private RestTemplate restTemplate;
 
    @Override
    public Order queryOrder(String orderId) {
        return orderRepository.findById(orderId).orElse(null);
    }
 
    @Override
    public boolean isTicketLeft(String trainNumber, String from, String to) {
        String url = "http://ts.sdo.com/train/left_ticket/?train_date=2023-03-01&station_train_code=" + trainNumber + "&from_station=" + from + "&to_station=" + to;
        String response = restTemplate.getForObject(url, String.class);
        // 根据响应结果判断是否有票
        return !"无".equals(response);
    }
 
    @Override
    public Order purchaseTicket(String trainNumber, String from, String to) {
        // 模拟下单操作
        Order order = new Order();
        order.setOrderId(UUID.randomUUID().toString());
        order.setTrainNumber(trainNumber);
        order.setFrom(from);
        order.setTo(to);
        orderRepository.save(order);
        return order;
    }
}
 
// 实体类Order
@Entity
public class Order {
    @Id
    private String orderId;
    private String trainNumber;
    private String from;
    private String to;
    // 省略getter和setter
}
 
// 仓库接口OrderRepository
public interface OrderRepository extends JpaRepository<Order, String> {
}
 
// 控制器类TicketController
@RestController
public class TicketController {
 
    @Autowired
    private TicketService ticketService;
 
    @GetMapping("/query_order")
    public Order queryOrder(@RequestParam String orderId) {
        return ticketService.queryOrder(orderId);
    }
 
    @GetMapping("/is_ticket_left")
    public boolean isTicketLeft(@RequestParam String trainNumber, @RequestParam String from, @RequestParam String to) {
2024-09-06

Spring Boot整合Shiro主要有两种方式:

  1. 使用Shiro Spring Boot Starter
  2. 手动配置

1. 使用Shiro Spring Boot Starter

首先,添加依赖到你的pom.xml




<dependency>
    <groupId>org.apache.shiro</groupId>
    <artifactId>shiro-spring-boot-starter</artifactId>
    <version>版本号</version>
</dependency>

然后,在application.propertiesapplication.yml中配置Shiro:




# 配置Shiro
shiro.sessionManager.globalSessionTimeout = 800000
shiro.unauthorizedUrl = /unauthorized
shiro.user.cookie = user
shiro.user.cookie.maxAge = 3600
shiro.user.cookie.path = /

2. 手动配置

在Spring Boot的配置类中添加Shiro配置:




@Configuration
public class ShiroConfig {
 
    @Bean
    public Realm realm() {
        // 配置你的Realm
        return new YourRealm();
    }
 
    @Bean
    public DefaultWebSecurityManager securityManager() {
        DefaultWebSecurityManager manager = new DefaultWebSecurityManager();
        manager.setRealm(realm());
        // 配置其他组件
        return manager;
    }
 
    @Bean
    public ShiroFilterFactoryBean shiroFilterFactoryBean(DefaultWebSecurityManager securityManager) {
        ShiroFilterFactoryBean factoryBean = new ShiroFilterFactoryBean();
        factoryBean.setSecurityManager(securityManager);
        // 配置过滤链
        return factoryBean;
    }
}

application.propertiesapplication.yml中配置Shiro:




# 配置Shiro
shiro.sessionManager.globalSessionTimeout = 800000
shiro.unauthorizedUrl = /unauthorized
shiro.user.cookie = user
shiro.user.cookie.maxAge = 3600
shiro.user.cookie.path = /

以上两种方式均可以整合Shiro到Spring Boot项目中,具体使用哪一种取决于你的项目需求和偏好。

2024-09-06

以下是一个简化的Spring Cloud Gateway配合JWT实现鉴权的示例:

  1. 添加依赖(pom.xml):



<dependencies>
    <!-- Spring Cloud Gateway -->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-gateway</artifactId>
    </dependency>
    <!-- Spring Cloud Gateway Filter for JWT -->
    <dependency>
        <groupId>com.marcosbarbero.cloud</groupId>
        <artifactId>spring-cloud-gateway-core-filter-jwt-rewrite</artifactId>
        <version>2.2.1.RELEASE</version>
    </dependency>
    <!-- JWT -->
    <dependency>
        <groupId>io.jsonwebtoken</groupId>
        <artifactId>jjwt</artifactId>
        <version>0.9.1</version>
    </dependency>
</dependencies>
  1. 配置文件(application.yml):



spring:
  cloud:
    gateway:
      routes:
        - id: service-id
          uri: http://localhost:8080
          predicates:
            - Path=/service/**
          filters:
            - StripPrefix=1
            - name: JwtRequestWrapperFilter
            - name: JwtDecodeFilter
              args:
                public-key: "your_public_key"
                token-is-optional: false
  1. 配置JWT过滤器(FilterConfig.java):



@Configuration
public class FilterConfig {
 
    @Bean
    public JwtFilter jwtFilter() {
        return new JwtFilter("your_public_key");
    }
}
  1. JWT过滤器实现(JwtFilter.java):



public class JwtFilter implements GatewayFilter, Ordered {
    private String publicKey;
 
    public JwtFilter(String publicKey) {
        this.publicKey = publicKey;
    }
 
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        String token = exchange.getRequest().getHeaders().getFi
2024-09-06

在Spring Cloud Gateway中,跨域问题通常是由于浏览器的同源策略导致的,它阻止了来自不同源(域名、协议或端口)的Web页面请求访问另一个源的资源。Spring Cloud Gateway提供了一个全局过滤器来解决跨域问题。

解决方案:

  1. 添加全局跨域过滤器:



@Bean
public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
    return builder.routes()
            .route("cross-origin", r -> r.order(0)
                    .filter(exposeHeadersGatewayFilterFactory.apply(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN))
                    .uri("http://localhost:8080/")
                    .id("cross_origin_route")
            )
            .build();
}
  1. 配置跨域过滤器:



spring:
  cloud:
    gateway:
      globalcors:
        add-to-simple-url-handler-mapping: true
        corsConfigurations:
          '[/**]':
            allowedOrigins: "*"
            allowedMethods:
            - GET
            - POST
            - DELETE
            - PUT
            - OPTIONS

在上述配置中,add-to-simple-url-handler-mapping 属性设置为 true 表示启用简单URL的处理映射,allowedOrigins 属性设置为 "*" 表示允许所有域进行跨域请求。

注意:在生产环境中,应该将 allowedOrigins 设置为特定的域,以保证安全。

2024-09-06

在Spring Boot项目中优雅停止服务,通常指的是在关闭应用程序时能够处理完正在进行的任务、断开数据库连接、通知监控系统等。以下是五种优雅停止服务的方法:

  1. 使用SpringApplication.exit()退出



@SpringBootApplication
public class MyApp {
    private static ConfigurableApplicationContext context;
 
    public static void main(String[] args) {
        context = SpringApplication.run(MyApp.class, args);
    }
 
    public static void exit() {
        SpringApplication.exit(context, () -> 0);
        context.close();
    }
}
  1. 使用@PreDestroy注解



@Component
public class MyService {
    @PreDestroy
    public void onShutdown() {
        // 执行清理工作
    }
}
  1. 使用DisposableBean接口



@Component
public class MyService implements DisposableBean {
    @Override
    public void destroy() throws Exception {
        // 执行清理工作
    }
}
  1. 使用CountDownLatch



@Component
public class GracefulShutdown {
    private static final CountDownLatch latch = new CountDownLatch(1);
 
    public void shutdown() {
        try {
            latch.await(); // 阻塞等待
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }
 
    public void stop(Runnable callback) {
        callback.run(); // 执行清理工作
        latch.countDown(); // 允许阻塞的线程继续
    }
}
  1. 使用ApplicationListener<ContextClosedEvent>监听关闭事件



@Component
public class GracefulShutdownListener implements ApplicationListener<ContextClosedEvent> {
    @Override
    public void onApplicationEvent(ContextClosedEvent event) {
        // 执行清理工作
    }
}

以上方法可以根据实际需求选择使用,以实现优雅停止服务。

2024-09-06

要在Spring Boot项目中接入文心一言API,你需要做以下几步:

  1. 在Spring Boot项目中添加文心一言API的依赖(如果有的话)。
  2. 获取API Key。
  3. 创建服务来调用文心一言API。
  4. 在Vue项目中发送请求到Spring Boot服务器,并展示结果。

以下是一个简化的例子:

步骤1:添加依赖(如果有必要)




<!-- 示例,具体依赖请参考文心一言官方文档 -->
<dependency>
    <groupId>com.baidu.aip</groupId>
    <artifactId>java-sdk</artifactId>
    <version>您的版本号</version>
</dependency>

步骤2:获取API Key

在使用文心一言API之前,你需要在百度开发者中心注册账号,创建应用以获取API Key。

步骤3:创建服务




import com.baidu.aip.nlp.AipNlp;
 
@Service
public class DuerOSService {
 
    @Value("${dueros.apiKey}")
    private String apiKey;
 
    @Value("${dueros.secretKey}")
    private String secretKey;
 
    private AipNlp client;
 
    @PostConstruct
    public void init() {
        client = new AipNlp(apiKey, secretKey);
    }
 
    public String talk(String text) {
        // 调用文心一言API
        HashMap<String, Object> options = new HashMap<>();
        // 设置选项,如设置用户ID等
        String response = client.simsimi(text, options);
        return response;
    }
}

步骤4:在Vue中发送请求




<template>
  <div>
    <input v-model="message" @keyup.enter="sendMessage" />
    <button @click="sendMessage">发送</button>
    <div v-for="item in messages" :key="item.id">{{ item.content }}</div>
  </div>
</template>
 
<script>
export default {
  data() {
    return {
      message: "",
      messages: [],
    };
  },
  methods: {
    async sendMessage() {
      if (!this.message.trim()) {
        alert("不能发送空消息");
        return;
      }
      try {
        const response = await axios.post("/api/dueros", { message: this.message });
        this.messages.push({ id: Date.now(), content: response.data });
        this.message = "";
      } catch (error) {
        alert("发送失败:" + error.message);
      }
    },
  },
};
</script>

Spring Boot Controller




@RestController
@RequestMapping("/api")
public class DuerOSController {
 
    @Autowired
    private DuerOSService duerosService;
 
    @PostMapping("/dueros")
    public String talk(@RequestBody Map<String, String> request) {
        return duerosService.talk(request.get("message"));
    }
}

确保你已经在application.properties或application.yml中配置了dueros.apiKey