如何解決需要找不到的“java.lang.String”類型的bean

Question

我收到以下錯誤：

equired a bean of type 'java.lang.String' that could not be found.
08-Dec-2021 06:49:02      [sshexec] 
08-Dec-2021 06:49:02      [sshexec] The injection point has the following annotations:
08-Dec-2021 06:49:02      [sshexec] - @org.springframework.beans.factory.annotation.Autowired(required=true)
08-Dec-2021 06:49:02      [sshexec] 
08-Dec-2021 06:49:02      [sshexec] 
08-Dec-2021 06:49:02      [sshexec] Action:
08-Dec-2021 06:49:02      [sshexec] 
08-Dec-2021 06:49:02      [sshexec] Consider defining a bean of type 'java.lang.String' in your configuration.

以下是我的課程：

@Configuration
public class CloudConfig {
    
    @Autowired
    private ReadAwsApplicationProperties readAwsApplicationProperties;
    
    List<AmazonSNS> amazonSNSClientArray = new ArrayList<>();

    @Bean
    public List<AmazonSNS> amazonSnsClient() {
        
    
}

}

有人可以幫我解決問題嗎？ 感謝您的時間。

Answer 1

問題在於以下代碼片段：

@Bean
public AWSCredentialsProvider genericProvisioningAWSCredentials(String awsAccessKeyId, String awsSecretKeyId) {     
    return new AWSStaticCredentialsProvider(new BasicAWSCredentials(awsAccessKeyId, awsSecretKeyId));
}

這將指示 Spring 注入兩個您似乎尚未定義為 Spring 管理的 Bean 的String 。

在我看來，您實際上並不需要AWSCredentialsProvider作為 Spring 管理的 Bean（您只是在上面的方法中使用此方法構建AmazonSNSClientBuilder ），因此只需刪除@Bean注釋並將該方法設為私有：

@Configuration
public class CloudConfig {
    
    @Autowired
    private ReadAwsApplicationProperties readAwsApplicationProperties;
    
    List<AmazonSNS> amazonSNSClientArray = new ArrayList<>();

    @Bean
    public List<AmazonSNS> amazonSnsClient() {
        
        for (int i = 0; i < readAwsApplicationProperties.getEnv().size(); i++) 
        {
            amazonSNSClientArray.add(AmazonSNSClientBuilder.standard()
                .withRegion(readAwsApplicationProperties.getEnv().get(i).getGeneric().getProv().getAws().getRegion())
                .withCredentials(genericProvisioningAWSCredentials(readAwsApplicationProperties.getEnv().get(i).getGeneric().getProv().getAws().getAccessKeyId(), readAwsApplicationProperties.getEnv().get(i).getGeneric().getProv().getAws().getAwsSecretKeyId()))
                .build());
        }
        logger.info(" The size of sns client is " + amazonSNSClientArray.size());
        return amazonSNSClientArray;
    }
    
    private AWSCredentialsProvider genericProvisioningAWSCredentials(String awsAccessKeyId, String awsSecretKeyId) {     
        return new AWSStaticCredentialsProvider(new BasicAWSCredentials(awsAccessKeyId, awsSecretKeyId));
    }
}