一切都启动了，因为Spring没有正确配置 SimpleStorageProtocolResolver 。这个类负责在使用 ResourceLoader .时处理s3://协议有关更多详细信息，请参见问题： 无法在Spring示例中转换为org.springframework.core.io.WritableResource 。

所以，我不得不手动创建它。但是我也在使用LocalStack解决方案( https://github.com/localstack/localstack )，由于Spring没有手动配置端点的选项，所以我有(猜怎么着？)手动创建 AmazonS3Client 。

问题来了，当我在类 S3Configuration 类中创建两个bean时(参见下面)，只是跳过bean的创建。而且，当我试图将其连接到 S3Handler 类(请参见下面)时，会发生这样的错误:创建名为 S3Handler 的bean时出错:是否存在不可解析的循环引用？

但是，这里又来了一件事情，在这些类之间没有循环引用。

我已经简化了这个项目，所以我可以在这里发布：

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.7.RELEASE</version>
        <relativePath/>
    </parent>
    <groupId>io.mobi7.ms</groupId>
    <artifactId>mobi7-temp-ms-ibutton-worker</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <properties>
        <spring-cloud-version>2.1.4.RELEASE</spring-cloud-version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-aws</artifactId>
            <version>${spring-cloud-version}</version>
        </dependency>
    </dependencies>
</project>

S3Configuration.java

package io.mobi7.ms.ibutton.worker;
import com.amazonaws.auth.AWSCredentialsProvider;
import com.amazonaws.client.builder.AwsClientBuilder;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.aws.core.io.s3.SimpleStorageProtocolResolver;
import org.springframework.cloud.aws.core.region.RegionProvider;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.DefaultResourceLoader;
@Configuration
public class S3Configuration {
    @Bean("amazonS3Client") // THIS METHOD IS NOT BEING CALLED!!!
    public AmazonS3 amazonS3Client(AWSCredentialsProvider credentialsProvider,
                                   RegionProvider regionProvider,
                                   @Value("${cloud.aws.s3.default-endpoint}") String endpoint) {
        return AmazonS3ClientBuilder.standard()
            .withCredentials(credentialsProvider)
            .withEndpointConfiguration(
                new AwsClientBuilder.EndpointConfiguration(endpoint, regionProvider.getRegion().getName()))
            .build();
    @Autowired  // THIS METHOD IS NOT BEING CALLED!!!
    public void configureResourceLoader(@Qualifier("amazonS3Client") AmazonS3 amazonS3Client,
                                        DefaultResourceLoader resourceLoader) {
        SimpleStorageProtocolResolver simpleStorageProtocolResolver = new SimpleStorageProtocolResolver(amazonS3Client);
        // As we are calling it by hand, we must initialize it properly.
        simpleStorageProtocolResolver.afterPropertiesSet();
        resourceLoader.addProtocolResolver(simpleStorageProtocolResolver);
}

S3Handle.java

package io.mobi7.ms.ibutton.worker;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.model.S3ObjectSummary;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Component;
import java.util.List;
import java.util.stream.Collectors;
@Component
public class S3Handler {
    private AmazonS3 amazonS3Client;
    @Autowired
    public S3Handler(@Qualifier("amazonS3Client") AmazonS3 amazonS3Client) {
        this.amazonS3Client = amazonS3Client;
    public List<String> listFiles(String bucketName) {
        return amazonS3Client.listObjects(bucketName).getObjectSummaries().stream().map(S3ObjectSummary::getKey)
            .collect(Collectors.toList());
}

Application.java

package io.mobi7.ms.ibutton.worker;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.WebApplicationType;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        new SpringApplicationBuilder(Application.class).web(WebApplicationType.NONE).run(args);
    @Autowired