使用Java和Spring Integration构建企业集成解决方案

import org.springframework.context.annotation.Configuration;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.channel.DirectChannel;
import org.springframework.integration.core.MessageProducer;
import org.springframework.integration.transformer.Transformer;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.MessageHandler;
import org.springframework.messaging.MessagingException;
 
@Configuration
public class EnterpriseIntegrationSolution {
 
    @ServiceActivator(inputChannel = "toUpperCaseChannel")
    public MessageHandler upperCaseService() {
        return message -> {
            String payload = (String) message.getPayload();
            message = org.springframework.integration.message.MessageBuilder
                    .withPayload(payload.toUpperCase())
                    .copyHeaders(message.getHeaders())
                    .build();
        };
    }
 
    @Bean
    public MessageChannel toUpperCaseChannel() {
        return new DirectChannel();
    }
 
    @Bean
    public MessageChannel outputChannel() {
        return new DirectChannel();
    }
 
    @Bean
    @ServiceActivator(inputChannel = "toUpperCaseChannel")
    public MessageHandler logger() {
        return message -> {
            try {
                System.out.println("Received message: " + message);
            } catch (Exception e) {
                throw new MessagingException(message, "Failed to handle message", e);
            }
        };
    }
 
    @Bean
    public MessageProducer customTransformerProducer() {
        Transformer transformer = message -> {
            String payload = (String) message.getPayload();
            return message.getHeaders().isEmpty() ? payload : payload.toUpperCase();
        };
        return MessageProducerSupport.fromTransformer(transformer, "outputChannel");
    }
}

这个代码示例展示了如何在Spring Integration中定义一个简单的服务，它接收一个字符串，将其转换为大写，并打印出来。同时，它也展示了如何使用MessageProducerSupport.fromTransformer来创建一个转换消息的生产者。这个解决方案提供了一个基本的参考框架，可以根据实际需求进行扩展和定制。