【java基础】File操作详解

File file = new File("newfile.txt");  if (file.createNewFile()) {      System.out.println("文件创建成功");  } else {      System.out.println("文件已经存在");  }

File dir = new File("newdirectory");  if (dir.mkdir()) {      System.out.println("目录创建成功");  } else {      System.out.println("目录已经存在");  }

File file = new File("file.txt");  if (file.delete()) {      System.out.println("文件删除成功");  } else {      System.out.println("文件删除失败");  }

File oldFile = new File("oldname.txt");  File newFile = new File("newname.txt");  if (oldFile.renameTo(newFile)) {      System.out.println("重命名成功");  } else {      System.out.println("重命名失败");  }

File file = new File("file.txt");  if (file.exists()) {      System.out.println("文件存在");  } else {      System.out.println("文件不存在");  }

File file = new File("file.txt");  long length = file.length();  System.out.println("文件长度: " + length + " bytes");

File file = new File("file.txt");  String absolutePath = file.getAbsolutePath();  System.out.println("绝对路径: " + absolutePath);

File dir = new File("directory");  File[] files = dir.listFiles();  if (files != null) {      for (File file : files) {          System.out.println(file.getName());      }  } else {      System.out.println("无法列出目录中的所有文件");  }

package com.croot.rims;

import com.croot.rims.dao.AttachmentinfoDao;import com.croot.rims.dao.ProjectMapper;import com.croot.rims.entity.Attachmentinfo;import com.croot.rims.entity.story.request.MappingFiles;import com.croot.rims.entity.story.request.StoreFiles;import com.croot.rims.service.story.StoryService;import org.junit.Test;import org.junit.runner.RunWith;import org.springframework.boot.test.context.SpringBootTest;import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;import java.io.File;import java.util.ArrayList;import java.util.List;
@RunWith(SpringRunner.class)@SpringBootTest(classes = RimsServerApplication.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)public class SynchronizeAttachmentsTask { 
    @Test    public void test() {        String basePath = "C:\\Users\\Administrator\\Desktop\\fsdownload";        File dir = new File(basePath);
        List<File> allFileList = new ArrayList<>();
        // 判断文件夹是否存在        if (!dir.exists()) {            System.out.println("目录不存在");            return;        }
        getAllFile(dir, allFileList);
        for (File file : allFileList) {            String fileName = file.getName();      System.out.println(fileName);
        }        System.out.println("该文件夹下共有" + allFileList.size() + "个文件");
    }    public static void getAllFile(File fileInput, List<File> allFileList) {        // 获取文件列表        File[] fileList = fileInput.listFiles();        assert fileList != null;        for (File file : fileList) {            if (file.isDirectory()) {                // 递归处理文件夹                // 如果不想统计子文件夹则可以将下一行注释掉                getAllFile(file, allFileList);            } else {                // 如果是文件则将其加入到文件数组中                allFileList.add(file);            }        }    }
}