Question

我是Spring Integration的新手。我正在研究解决方案，但在使用入站文件适配器（FileReadingMessageSource）时我遇到了一个特定的问题。我必须从不同的目录中读取文件并处理它们并将文件保存在不同的目录中。据我所知，目录名称是固定在流程的开头。有人可以帮我改变不同请求的目录名。

我尝试了以下方法。首先，我不确定它是否是正确的方法，虽然它只适用于一个目录。我认为Poller正在等待更多文件，并且从未回过头来阅读另一个目录。

@SpringBootApplication
@EnableIntegration
@IntegrationComponentScan
public class SiSampleFileProcessor {

    @Autowired
    MyFileProcessor myFileProcessor;

    @Value("${si.outdir}")
    String outDir;

    @Autowired
    Environment env;

    public static void main(String[] args) throws IOException {
        ConfigurableApplicationContext ctx = new SpringApplication(SiSampleFileProcessor.class).run(args);
        FileProcessingService gateway = ctx.getBean(FileProcessingService.class);
        boolean process = true;
        while (process) {
            System.out.println("Please enter the input Directory: ");
            String inDir = new Scanner(System.in).nextLine();
            if ( inDir.isEmpty() || inDir.equals("exit") ) {
                process=false;
            } else {
                System.out.println("Processing... " + inDir);
                gateway.processFilesin(inDir);
            }
        }
        ctx.close();
    }

    @MessagingGateway(defaultRequestChannel="requestChannel")
    public interface FileProcessingService {
        String processFilesin( String inputDir );
    }

    @Bean(name = PollerMetadata.DEFAULT_POLLER)
    public PollerMetadata poller() {                                      
    return Pollers.fixedDelay(1000).get();
    }

    @Bean
    public MessageChannel requestChannel() {
        return new DirectChannel();
    }

    @ServiceActivator(inputChannel = "requestChannel")
    @Bean 
    GenericHandler<String> fileReader() {
        return new GenericHandler<String>() {
            @Override
            public Object handle(String p, Map<String, Object> map) {
                FileReadingMessageSource fileSource = new FileReadingMessageSource();
                fileSource.setDirectory(new File(p));
                Message<File> msg;
                while( (msg = fileSource.receive()) != null ) {
                    fileInChannel().send(msg);
                }
                return null;  // Not sure what to return!
            }
        };
    }

    @Bean
    public MessageChannel fileInChannel() {
        return MessageChannels.queue("fileIn").get();
    }

    @Bean
    public IntegrationFlow fileProcessingFlow() {
        return IntegrationFlows.from(fileInChannel())
                .handle(myFileProcessor)
                .handle(Files.outboundAdapter(new File(outDir)).autoCreateDirectory(true).get())
                .get();
    }    
}

编辑：基于加里的回应取代了一些方法

@MessagingGateway(defaultRequestChannel="requestChannel")
public interface FileProcessingService {
    boolean processFilesin( String inputDir );
}

@ServiceActivator(inputChannel = "requestChannel")
public boolean fileReader(String inDir) {
    FileReadingMessageSource fileSource = new FileReadingMessageSource();
    fileSource.setDirectory(new File(inDir));
    fileSource.afterPropertiesSet();
    fileSource.start();
    Message<File> msg;
    while ((msg = fileSource.receive()) != null) {
        fileInChannel().send(msg);
    }
    fileSource.stop();
    System.out.println("Sent all files in directory: " + inDir);
    return true;
}

现在它按预期工作了。

Answer 1

FileReadingMessageSource在内部使用DirectoryScanner;它通常在注入属性后由Spring设置。由于您在Spring之外管理对象，因此需要调用Spring bean初始化和生命周期方法afterPropertiesSet()，start()和stop()。

当接收返回null时调用stop()。

> return null;  // Not sure what to return!

如果什么都不返回，你的调用线程将挂在网关中等待响应。您可以更改网关以返回void，或者，因为您的网关需要一个String，只需返回一些值。

但是，您的调用代码无论如何都不会查看结果。

> gateway.processFilesin(inDir);

另外，从@Bean移除@ServiceActivator;使用该样式，bean类型必须为MessageHandler。

Answer 2

您可以使用此代码

FileProcessor.java

import org.springframework.messaging.Message;
import org.springframework.stereotype.Component;
@Component
public class FileProcessor {

    private static final String HEADER_FILE_NAME = "file_name";
    private static final String MSG = "%s received. Content: %s";

    public void process(Message<String> msg) {
        String fileName = (String) msg.getHeaders().get(HEADER_FILE_NAME);
        String content = msg.getPayload();
        //System.out.println(String.format(MSG, fileName, content));
        System.out.println(content);

    }
}

LastModifiedFileFilter.java

package com.example.demo;

import org.springframework.integration.file.filters.AbstractFileListFilter;

import java.io.File;
import java.util.HashMap;
import java.util.Map;

public class LastModifiedFileFilter extends AbstractFileListFilter<File> {
    private final Map<String, Long> files = new HashMap<>();
    private final Object monitor = new Object();

    @Override
    protected boolean accept(File file) {
        synchronized (this.monitor) {
            Long previousModifiedTime = files.put(file.getName(), file.lastModified());

            return previousModifiedTime == null || previousModifiedTime != file.lastModified();
        }
    }
}

Main Class = DemoApplication.java

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration;
import java.io.File;
import java.io.IOException;
import java.nio.charset.Charset;
import org.apache.commons.io.FileUtils;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.integration.annotation.Aggregator;
import org.springframework.integration.annotation.InboundChannelAdapter;
import org.springframework.integration.annotation.Poller;
import org.springframework.integration.channel.DirectChannel;
import org.springframework.integration.channel.QueueChannel;
import org.springframework.integration.core.MessageSource;
import org.springframework.integration.dsl.IntegrationFlow;
import org.springframework.integration.dsl.IntegrationFlows;
import org.springframework.integration.dsl.channel.MessageChannels;
import org.springframework.integration.dsl.core.Pollers;
import org.springframework.integration.file.FileReadingMessageSource;
import org.springframework.integration.file.filters.CompositeFileListFilter;
import org.springframework.integration.file.filters.SimplePatternFileListFilter;
import org.springframework.integration.file.transformer.FileToStringTransformer;
import org.springframework.integration.scheduling.PollerMetadata;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.PollableChannel;
import org.springframework.stereotype.Component;


@SpringBootApplication
@Configuration
public class DemoApplication {

    private static final String DIRECTORY = "E:/usmandata/logs/input/";

    public static void main(String[] args) throws IOException, InterruptedException {
        SpringApplication.run(DemoApplication.class, args);


    }


    @Bean
    public IntegrationFlow processFileFlow() {
        return IntegrationFlows
                .from("fileInputChannel")
                .transform(fileToStringTransformer())
                .handle("fileProcessor", "process").get();
    }

    @Bean
    public MessageChannel fileInputChannel() {
        return new DirectChannel();
    }

    @Bean
    @InboundChannelAdapter(value = "fileInputChannel", poller = @Poller(fixedDelay = "1000"))
    public MessageSource<File> fileReadingMessageSource() {
        CompositeFileListFilter<File> filters =new CompositeFileListFilter<>();
        filters.addFilter(new SimplePatternFileListFilter("*.log"));
        filters.addFilter(new LastModifiedFileFilter());

        FileReadingMessageSource source = new FileReadingMessageSource();
        source.setAutoCreateDirectory(true);
        source.setDirectory(new File(DIRECTORY));
        source.setFilter(filters);

        return source;
    }

    @Bean
    public FileToStringTransformer fileToStringTransformer() {
        return new FileToStringTransformer();
    }

    @Bean
    public FileProcessor fileProcessor() {
        return new FileProcessor();
    }
}

Spring Integration文件阅读

2 个答案: