Apache Commons IO-FileAlterationObserver

FileAlterationObserver는 루트 디렉토리 아래의 파일 상태를 나타내며 파일 시스템을 확인하고 리스너에게 생성, 변경 또는 삭제 이벤트를 알립니다.

클래스 선언

다음은에 대한 선언입니다.

org.apache.commons.io.monitor.FileAlterationObserver 클래스-

public class FileAlterationObserver
   extends Object implements Serializable

FileAlterationObserver 클래스의 예

다음은 파싱해야하는 입력 파일입니다.

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IOTester.java

import java.io.File;
import java.io.IOException;
import org.apache.commons.io.FileDeleteStrategy;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.monitor.FileAlterationListenerAdaptor;
import org.apache.commons.io.monitor.FileAlterationMonitor;
import org.apache.commons.io.monitor.FileAlterationObserver;
public class IOTester {
   public static void main(String[] args) {
      try {
         usingFileAlterationObserver();
      } catch(IOException e) {
         System.out.println(e.getMessage());
      }
   }
   public static void usingFileAlterationObserver() throws IOException {
      //get the file object
      File inputFile = FileUtils.getFile("input.txt");
      String absolutePath = inputFile.getAbsolutePath();
      String parent = absolutePath.substring(0,absolutePath.indexOf("input.txt"));
      File parentDirectory = FileUtils.getFile(parent);
      FileAlterationObserver observer = new
      FileAlterationObserver(parentDirectory);
      observer.addListener(new FileAlterationListenerAdaptor() {
         @Override
         public void onDirectoryCreate(File file) {
            System.out.println("Folder created: " + file.getName());
         }
         @Override
            public void onDirectoryDelete(File file) {
               System.out.println("Folder deleted: " + file.getName());
            }
         @Override
            public void onFileCreate(File file) {
               System.out.println("File created: " + file.getName());
            }
         @Override
            public void onFileDelete(File file) {
               Syst em.out.println("File deleted: " + file.getName());
            }
        });
       //create a monitor to check changes after every 500 ms
       FileAlterationMonitor monitor = new FileAlterationMonitor(500, observer);
       try {
          monitor.start();
         //create a new directory
         File newFolder = new File("test");
         File newFile = new File("test1");
         newFolder.mkdirs();
         Thread.sleep(1000);
         newFile.createNewFile();
         Thread.sleep(1000);
         FileDeleteStrategy.NORMAL.delete(newFolder);
         Thread.sleep(1000);
         FileDeleteStrategy.NORMAL.delete(newFile);
         Thread.sleep(1000);
         monitor.stop(10000);
      } catch(IOException e) {
         System.out.println(e.getMessage());
      } catch(InterruptedException e) {
         System.out.println(e.getMessage());
      } catch (Exception e) {
         System.out.println(e.getMessage());
      }
   }
}

산출

다음 결과를 인쇄합니다.

Folder created: test
File created: test1
Folder deleted: test
File deleted: test1