下面是使用Apache Beam实现通配符递归搜索文件的代码示例:
import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.io.FileIO;
import org.apache.beam.sdk.io.fs.MatchResult;
import org.apache.beam.sdk.io.fs.MoveOptions;
import org.apache.beam.sdk.io.fs.ResourceId;
import org.apache.beam.sdk.options.PipelineOptionsFactory;
import org.apache.beam.sdk.transforms.DoFn;
import org.apache.beam.sdk.transforms.ParDo;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class FileSearch {
public static void main(String[] args) {
PipelineOptions options = PipelineOptionsFactory.create();
Pipeline pipeline = Pipeline.create(options);
String rootDirectory = "/path/to/root/directory";
String filePattern = "*.txt"; // 使用通配符来匹配文件名
pipeline
.apply("Search files", FileIO.match().filepattern(rootDirectory + "/**"))
.apply("Filter files", ParDo.of(new FilterFilesFn(filePattern)))
.apply("Print file paths", ParDo.of(new PrintFilePathsFn()));
pipeline.run().waitUntilFinish();
}
static class FilterFilesFn extends DoFn {
private final String filePattern;
public FilterFilesFn(String filePattern) {
this.filePattern = filePattern;
}
@ProcessElement
public void processElement(ProcessContext c) {
MatchResult.Metadata metadata = c.element();
String filePath = metadata.resourceId().toString();
Pattern pattern = Pattern.compile(filePattern);
Matcher matcher = pattern.matcher(filePath);
if (matcher.matches()) {
c.output(metadata);
}
}
}
static class PrintFilePathsFn extends DoFn {
@ProcessElement
public void processElement(ProcessContext c) {
MatchResult.Metadata metadata = c.element();
String filePath = metadata.resourceId().toString();
System.out.println(filePath);
}
}
}
上述代码中,我们使用FileIO.match().filepattern()
方法来匹配指定目录下的所有文件。然后使用ParDo
转换来过滤出符合通配符模式的文件,并使用另一个ParDo
转换来打印文件路径。
注意替换代码中的rootDirectory
和filePattern
为实际的目录和文件通配符。