apache camel s3组件 - 在前缀上指定后缀/正则表达式

I'm using the aws s3 component of Apache Camel. And I want to consume specific data only with an extension of .txt, how can this be achieved? According to camel documentation, it has a prefix options which is not suitable in my case since i want to filter based on extensions.I'm using the aws s3 component of Apache Camel.