java基础io流——File的告白（重温经典）

        public File(String pathname)
        public File(String parent,String child)
        public File(File parent,String child)

        File f1 = new File("E:\\huge.jpg");
        File f2 = new File("E:\\","huge.jpg");
        File f3 = new File("E:\\");
        File f4 = new File(f3,"huge.jpg");

        String path = f4.getAbsolutePath();
        File f5 = new File(path);
        System.out.println(f5);//E:\huge.jpg
        System.out.println(f1.getParent());//E:\
        System.out.println(f4.getAbsoluteFile());//E:\huge.jpg
        System.out.println(f5.getAbsolutePath());//E:\huge.jpg

        File f1= new File("e:/io");
        //System.out.println(f1.mkdir());
        File f2= new File("e:/io/demo1/test1");
        //System.out.println(f2.mkdirs());

        File f3= new File("e:/io/demo1/test1/t.txt");
        try {
            System.out.println(f3.createNewFile());
        } catch (IOException e) {
            e.printStackTrace();
        }

        File f1= new File("e:/io/demo1/test1/t.txt");
        //f1.delete();
        File f2= new File("e:/io/demo1/test1");
        f1.delete();
        System.out.println(f2.delete());//test1下不为空，false

//    重命名  xfy1.txt 重命名为xfy2.txt
      File f1 = new File("e:/xfy1.txt");
      File f2 = new File("e:/xfy2.txt");        f1.renameTo(f2);

        //剪切
        File f3 = new File("e:/xfy1.txt");
        //f3.createNewFile();
        File f4 = new File("xfy1.txt");
        f3.renameTo(f4);

        //剪切加重命名
//        File f5 = new File("xfy1.txt");
//        //f1.createNewFile();
//        File f6 = new File("e:/xfy2.txt");
//        f5.renameTo(f6);

/*
 * 判断功能:
 * public boolean isDirectory():判断是否是目录
 * public boolean isFile():判断是否是文件
 * public boolean exists():判断是否存在
 * public boolean canRead():判断是否可读
 * public boolean canWrite():判断是否可写
 * public boolean isHidden():判断是否隐藏
 */
 
 
        File f1 = new File("xfy1.txt");
        System.out.println(f1.exists());
        System.out.println(f1.isFile());
        System.out.println(f1.isDirectory());
        System.out.println(f1.canRead());
        System.out.println(f1.canRead());

/*
 * 获取功能：
 * public String getAbsolutePath()：获取绝对路径
 * public String getPath():获取相对路径
 * public String getName():获取名称
 * public long length():获取长度。字节数
 * public long lastModified():获取最后一次的修改时间，毫秒值
 */
 
 
 // 创建文件对象
        File file = new File("demo\\test.txt");

        System.out.println("getAbsolutePath:" + file.getAbsolutePath());
        System.out.println("getPath:" + file.getPath());
        System.out.println("getName:" + file.getName());
        System.out.println("length:" + file.length());
        System.out.println("lastModified:" + file.lastModified());
        Date d = new Date(f1.lastModified());
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
        String date = sdf.format(d);
        System.out.println(date);

/*
 * 获取功能：
 * public String[] list():获取指定目录下的所有文件或者文件夹的名称数组
 * public File[] listFiles():获取指定目录下的所有文件或者文件夹的File数组
 */
 
        File file = new File("e:/");
        String[] files = file.list();
        for (String s : files) {
            System.out.println(s);
        }
        System.out.println("------------");

        File[] filess = file.listFiles();
        for (File filess1 : filess) {
            System.out.println(filess1.getName());

        }

        File f = new File("e:/");
        File[] files = f.listFiles();
        for (File file : files) {
            if (file.isFile()) {
                if (file.getName().endsWith(".jpg")) {
                    System.out.println(file.getName());
                }
            }
        }

package io1;
import java.io.File;
import java.io.FileFilter;
import java.io.FilenameFilter;

/**
 * Create by stefan
 * Date on 2018-05-27  14:36
 * Convertion over Configuration!
 */

/*
 * 判断E盘目录下是否有后缀名为.jpg的文件，如果有，就输出此文件名称
 * A:先获取所有的，然后遍历的时候，依次判断，如果满足条件就输出。
 * B:获取的时候就已经是满足条件的了，然后输出即可。
 *
 * 要想实现这个效果，就必须学习一个接口：文件名称过滤器
 * public String[] list(FilenameFilter filter)
 * public File[] listFiles(FilenameFilter filter)
 */
public class demo8 {
    public static void main(String args[]){
        File file = new File("e:/");
//        File[] files = file.listFiles(new FilenameFilter() {
//            @Override
//            public boolean accept(File dir, String name) {
//                System.out.println(dir+name);
//                return new File(dir,name).isFile()&&name.endsWith(".jpg");
//            }
//        });
//        System.out.println("--------------------------------");
//        for (File file1 : files) {
//            System.out.println(file1.getName());
//        }

        File[] fs = file.listFiles(new FileFilter() {
            @Override
            public boolean accept(File pathname) {
                //System.out.println(pathname);
                return pathname.isFile()&&pathname.getName().endsWith(".jpg");
            }
        });

        for (File f : fs) {
            System.out.println(f.getName());
        }

//        file.list();
//        file.list(new FilenameFilter() {
//            @Override
//            public boolean accept(File dir, String name) {
//                return false;
//            }
//        });


    }
}

File f = new File("F:\\汤包\\IT时代\\一头扎进Hibernate4视频教程");
        File[] files = f.listFiles();
        for (File file : files) {
            String name =file.getName();
            //System.out.println(name);
            int start = name.indexOf("[");
            int end = name.indexOf("]");
            //[0,17)
            String newname = name.substring(start,end+1);
            //System.out.println(newname);

            System.out.println(name.substring(end+1));
            File newFile = new File(file.getParent(),name.substring(end+1));

            file.renameTo(newFile);
        }
    }