파일의 이름과 확장자 분리 / How to get name and extension of a file in java

파일의 이름과 확장자 분리 / How to get name and extension of a file in java

 

package test;
 
public class Test {
 
    public static void main(String[] args) {
 
        String file = "abcdef.pdf";
        int lastIndex = file.lastIndexOf(".");
 
        String fileName = file.substring(0, lastIndex);
        String extension = file.substring(lastIndex + 1);
 
        System.out.println("file name : " + fileName);
        System.out.println("file extension  : " + extension);
    }
}

 

package test;
 
import java.util.Optional;
 
public class Test {
 
    public static void main(String[] args) {
 
        String file = "abcdef.pdf";
 
        Optional<String> fileName = getFileNameByStringHandling(file);
        System.out.println("file name : " + fileName.get());
 
        Optional<String> extension = getExtensionByStringHandling(file);
        System.out.println("file extension  : " + extension.get());
    }
 
    public static Optional<String> getFileNameByStringHandling(String filename) {
        return Optional.ofNullable(filename).filter(f -> f.contains("."))
                .map(f -> f.substring(0, filename.lastIndexOf(".")));
    }
 
    public static Optional<String> getExtensionByStringHandling(String filename) {
        return Optional.ofNullable(filename).filter(f -> f.contains("."))
                .map(f -> f.substring(filename.lastIndexOf(".") + 1));
    }
}