与Http出站网关启动时的问题

Question

我是Spring的新手，我正在尝试开发一个应用程序，该应用程序简单地(1)轮询一个扩展名为.dat的新文件，其中包含csv格式的数据(2)为每一行初始化类RecordDTO的域POJO对象，最后(3)将该对象作为有效负载发送到带有POST的REST服务。

为此，我尝试使用Java进行Spring集成。

我遇到的问题是以下VerifyError / HttpRequestExecutingMessageHandler overrides final method onInit.异常。

2016-07-22 10:01:38.965 ERROR 4460 --- [           main] o.s.boot.SpringApplication               : Application startup failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'upcase' defined in eu.softeco.examples.SpringBootIntegrationTestApplication: Initialization of bean failed; nest
ed exception is java.lang.VerifyError: class org.springframework.integration.http.outbound.HttpRequestExecutingMessageHandler overrides final method onInit.()V
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) ~[spring-beans-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.1.RELEASE.jar:4.3.1.RELEASE]

...

Caused by: java.lang.VerifyError: class org.springframework.integration.http.outbound.HttpRequestExecutingMessageHandler overrides final method onInit.()V
    at java.lang.ClassLoader.defineClass1(Native Method) ~[na:1.8.0_45]
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760) ~[na:1.8.0_45]
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) ~[na:1.8.0_45]

...

下面是有关我的代码和maven配置的相关细节。请不要这样

1)在将任何数据放入输入文件夹之前，问题就在启动时。

2)如果我用简单(注释) System.out.println替换最终的Http System.out.println步骤，一切都会正常工作。

下面是代码/配置详细信息。这是我使用定义的主要Spring应用程序类：

@SpringBootApplication
@EnableIntegration 
@IntegrationComponentScan
public class SpringBootIntegrationTestApplication {

        ...

    public static void main(String[] args) {
          SpringApplication.run(SpringBootIntegrationTestApplication.class, args);
    }

    /**
     * Inbound FileReadingMessageSource 
     */

    @Bean
    @InboundChannelAdapter(channel = "upcase.input", poller = @Poller(fixedDelay = "4000"))
    public MessageSource<File> fileReadingMessageSource() {
         FileReadingMessageSource source = new FileReadingMessageSource();
         source.setDirectory(new File(INBOUND_PATH));
         source.setFilter(new SimplePatternFileListFilter("*.dat"));
         return source;
    }


    /**
     * Spring Integration Java DSL Flow
         */

    @Bean
    public IntegrationFlow upcase() {

        FileToStringTransformer fileToStringTranformer = Transformers.fileToString();
        fileToStringTranformer.setDeleteFiles(true);

            return flow -> flow

                    // get string contents from fie 
                    .transform(fileToStringTranformer) 

                    // split into individual lines
                    .split( s -> s.applySequence(true).get().getT2().setDelimiters("\n"))

                    // cleanup lines from trailing returns
                    .transform( (String s) -> s.replace("\n", "").replace("\r", "") )

                    // convert csv string to RecordDTO object
                    .transform("@recordFromCsvTransformer.transform(payload)")

                    // print on System.out
                    // .handle(m -> System.out.println(m.getPayload()))

                    // send to 
                    .handle(Http.outboundGateway("http://localhost:8080/records")
                                .httpMethod(HttpMethod.POST)
                        .expectedResponseType(RecordDTO.class));


    }

}

在RecordFromCsvTransformer类下面

@Component
public class RecordFromCsvTransformer
{
    @Transformer
    public RecordDTO transform(String csvline) throws Exception {

        RecordDTO record = new RecordDTO();

        ... parse csv and initialize record's fields...

        return record;
    }

}

最后给出了pom.xml的相关部分(依赖关系)；

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.4.0.RC1</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>

...

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-integration</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.integration</groupId>
        <artifactId>spring-integration-file</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.integration</groupId>
        <artifactId>spring-integration-http</artifactId>
        <version>2.1.0.RELEASE</version>
    </dependency>
    ...
</dependencies>

...

作为一个附带的问题，有人能建议我一些好的教程/入门指南来学习与Java注释/Java的Spring集成吗？到目前为止，我只找到了基于配置的入门指南或关于Java注释/DSL的材料，但这已经需要对Spring的先验知识。

Answer 1

<version>2.1.0.RELEASE</version>

该版本的Spring与maven临时引入的spring-integration-core版本不匹配。

您需要使用相同版本的所有spring集成-*文件-检查哪个版本的spring-integration-file是由引导和使用相同的版本。