深入了解Java File对象的使用【java基础】

目录

• 1.File对象　
• 2.创建文件
• 3.文件的相关操作

//方式一
    @Test
    public void create01(){
        try {
            String path = URLDecoder.decode("D:博客园wjj1.txt","UTF-8");//解决中文乱码，转UTF-8
            File file = new File(path);
            file.createNewFile();
            System.out.println("创建成功01");
        } catch (UnsupportedEncodingException e) {//decode方法需要抛异常或捕获异常
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

//方式二
    @Test
    public void create02(){
        String path = null;
        try {
            path = URLDecoder.decode("D:博客园","UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        File parentFile = new File(path);//父目录文件
        String fileName = "wjj2.txt";//子路径
        File file = new File(parentFile, fileName);
        try {
            file.createNewFile();
            System.out.println("创建成功02");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

//方式三
    @Test
    public void create03() throws Exception{//抛异常
        String path = URLDecoder.decode("D:博客园","UTF-8");
        String filePath = "wjj3.txt";
        File file = new File(path, filePath);
        file.createNewFile();
        System.out.println("创建成功03");
    }

@Test
    public void info() throws Exception{
        //创建文件对象
        String path = URLDecoder.decode("D:博客园wjj1.txt","UTF-8");
        File file = new File(path);
        System.out.println("文件名:"+file.getName());
        System.out.println("文件绝对路径:"+file.getAbsolutePath());
        System.out.println("文件父目录:"+file.getParent());
        System.out.println("文件大小(字节):"+file.length());
        System.out.println("文件是否存在:"+file.exists());
        System.out.println("是否是文件:"+file.isFile());
        System.out.println("是否是目录:"+file.isDirectory());
    }

@Test
    public void fileDelete() throws Exception{
        String path = URLDecoder.decode("D:博客园wjj1.txt","UTF-8");
        File file = new File(path);
        if (file.exists()){
            if (file.delete()){
                System.out.println(path+"删除成功");
            }else {
                System.out.println(path+"删除失败");
            }
        }else {
            System.out.println("文件不存在");
        }
    }

@Test
    public void isMkdir() throws Exception{
        String path = URLDecoder.decode("D:博客园wjj1","UTF-8");
        File file = new File(path);
        if (file.exists()){
            System.out.println(path+"该目录已存在");
        }else {
            if (file.mkdirs()){
                System.out.println("创建成功");
            }else {
                System.out.println("创建失败");
            }
        }
    }