/*** File类：文件的创建、删除、重命名、得到路径、创建时间等，是唯一与文件本身有关的操作类*/
public class Main {public static void main(String[] args) {//File.separator 表示分隔符File f1 = new File("c:" + File.separator + "fuck" + File.separator + "javaTest1.txt");String s1 = File.pathSeparator; //路径分隔符System.out.println(File.separator + "  " + s1);boolean b1 = f1.exists(); //文件是否存在
        System.out.println(b1);if (!b1) {try {boolean bt1 = f1.createNewFile(); //创建文件
                System.out.println(bt1);} catch (IOException e) {e.printStackTrace();}}System.out.println(f1.delete()); //删除文件//System.out.println(""); 快捷键：打sout,然后中按Tab键 System.out.println(f1.getParent()); //得到文件的上一级路径
System.out.println(f1.isDirectory()); //判断是否是目录
        File f2 = new File("c:" + File.separator + "fuck" + File.separator);String[] fname = f2.list(); //列出文件夹中的所有文件名for(String i:fname) System.out.println(i);File[] files = f2.listFiles(); //列出文件中的所有文件，以file数组返回for(File i:files) System.out.println(i.getName()+" "+i.length());File f3 = new File("c:\\fuck\\JavaTest1"); System.out.println(f3.mkdir()); //创建文件夹
        f3.delete();System.out.println(f3.renameTo(new File("c:\\fuck\\JavaTest2"))); //重命名
    }
}

/*** 在某个目录中找到某个扩展名的所有文件*/
public class Main {private static int num = 0;public static void findFile(File f,String extName){if(f==null)return;else{if(f.isDirectory()){File[] fs = f.listFiles();if(fs!=null){for(File i:fs)findFile(i,extName);}}else{String path = f.getPath().toLowerCase();if(path.endsWith(extName)){System.out.println(f.getPath());++num;}}}}public static void main(String[] args) {File  f = new File("c:\\fuck\\");String extName = ".cpp";findFile(f,extName);System.out.println(num);}
}

/*** IO流：输入输出流* 流：一组有顺序的，有起点和终点的字节集合，是对数据传输的总称或抽象。* 流的本质是数据传输，根据数据传输特性将流抽象为各种类，方便更直观的进行数据操作。* 根据处理数据类型的不同分为：1.字符流      2.字节流* 根据数据流向不同分为：1.输入流(程序从外部读取)       2.输出流（程序将数据写到外部）* * OutputStream类：接受输出字节并将这些字节发送到某个接收器*/
public class Main {public static void main(String[] args) {//write1();
        write2();System.out.println("finished.");}/*** 字节输出流方式一：每次输出一个字节*/public static void write1(){OutputStream out = null;try {out = new FileOutputStream("c:\\fuck\\javaTest1.txt");String info = "helloIO";byte[] bs = info.getBytes();for(int i=0;i<bs.length;++i)out.write(bs[i]);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();} finally {try {out.close();} catch (IOException ex) {ex.printStackTrace();}}}/*** 字节输出流方式二：每次输出指定大小字节*/public static void write2(){OutputStream out = null;try {out = new FileOutputStream("c:\\fuck\\javaTest1.txt",true); //参数true表示追加输出 String info = "hello fish7";byte[] bs = info.getBytes();//out.write(bs);out.write(bs,0,5);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();} finally {try {out.close();} catch (IOException ex) {ex.printStackTrace();}}}
}

public class Main {public static void main(String[] args) {//read1();
//        read2();
        read3();System.out.println("finished.");}/*** 字节输入流的读取方式一：每次读取一个字节*/public static void read1(){InputStream  in = null;try {in = new FileInputStream("c:\\fuck\\javaTest1.txt");int bs = -1; //定义一个字节，-1表示没有数据while((bs = in.read())!=-1){System.out.print((char)bs);     }System.out.println("");} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();} finally{try {in.close();} catch (IOException ex) {ex.printStackTrace();}}}/*** 字节输入流的读取方式二：一次性读取所有字节（适合不太大的文件）*/public static void read2(){InputStream in = null;try {File f = new File("c:\\fuck\\javaTest1.txt");in = new FileInputStream(f);byte[] bs = new byte[(int)f.length()]; //根据文件大小构造字节数组int len = in.read(bs);System.out.println(new String(bs));System.out.println("len = "+len);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();} finally{try {in.close();} catch (IOException ex) {ex.printStackTrace();}}}/*** 字节输入流的读取方式三：每次读取指定大小的字节（折中的方法）*/public static void read3(){InputStream in = null;try {File f = new File("c:\\fuck\\javaTest1.txt");in = new FileInputStream(f);byte[] bs = new byte[5];int len = -1; //每次读取的实际长度StringBuilder sb = new StringBuilder();while((len=in.read(bs))!=-1){sb.append(new String(bs,0,len));}System.out.println(sb);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();} finally{try {in.close();} catch (IOException ex) {ex.printStackTrace();}}}
}

/*** 字符流：底层也是用字节流实现的*/
public class Main {public static void main(String[] args) {writer1();System.out.println("finished.");}/*** 字符输出流方式一：以字符数组方式输出*/public static void writer1(){Writer out = null;try {File f = new File("c:\\fuck\\javaTest1.txt");out = new FileWriter(f,true); //true表示追加方式 String info = "good good study, day day up.";//out.write(info.toCharArray());
            out.write(info);} catch (IOException ex) {ex.printStackTrace();} finally{try{out.close();} catch (IOException ex) {ex.printStackTrace();}}}
}

/*** 字符流：底层也是用字节流实现的*/
public class Main {public static void main(String[] args) {//byteReader(); //输出一堆乱码
        reader1();System.out.println("finished.");}/*** 字符输入流方式一：使用指定大小的字符数组输入*/public static void reader1(){File f = new File("c:\\fuck\\javaTest1.txt");try {Reader in = new FileReader(f);char[] cs = new char[10];int len = -1;StringBuilder sb = new StringBuilder();while((len=in.read(cs))!=-1){sb.append(new String(cs,0,len));}in.close();System.out.println(sb);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();}}/*** 使用字节流读取文本文件*/public static void byteReader(){File f = new File("c:\\fuck\\javaTest1.txt");try {InputStream in = new FileInputStream(f);byte[] bs = new byte[10];int len = -1;StringBuilder sb = new StringBuilder();while((len=in.read(bs))!=-1){sb.append(new String(bs,0,len));}in.close();System.out.println(sb);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();}}
}

/*** 字符流：底层也是用字节流实现的* ：根据指定的编码，将1个或多个字节转化为java里的unicode字符，然后进行操作* 字符操作一般用Writer,Reader等，字节操作一般用InputStream,OutputStream以及各种包装类，比如：* BufferedInputStream和BufferedOutputStream等* 总结：如果你确认你要处理的流是可打印的字符，那么使用字符流会简单些，如果不确认，那么用字节流总是不会错的。*/
public class Main {public static void main(String[] args) {//byteReader(); //输出一堆乱码
        reader1();System.out.println("finished.");}/*** 字符输入流方式一：使用指定大小的字符数组输入*/public static void reader1(){File f = new File("c:\\fuck\\javaTest1.txt");try {Reader in = new FileReader(f);char[] cs = new char[10];int len = -1;StringBuilder sb = new StringBuilder();while((len=in.read(cs))!=-1){sb.append(new String(cs,0,len));}in.close();System.out.println(sb);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();}}/*** 使用字节流读取文本文件*/public static void byteReader(){File f = new File("c:\\fuck\\javaTest1.txt");try {InputStream in = new FileInputStream(f);byte[] bs = new byte[10];int len = -1;StringBuilder sb = new StringBuilder();while((len=in.read(bs))!=-1){sb.append(new String(bs,0,len));}in.close();System.out.println(sb);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();}}
}

/*** 指定一个盘符下的文件，把该文件复制到指定的目录下。*/
public class Main {public static void main(String[] args) {copyFile("c:\\fuck\\javaTest1.txt","c:\\fuck\\javaTest2.txt");copyFile("c:\\fuck\\ning.bmp","c:\\fuck\\ning2.txt"); //把.txt改成.bmp就可以看了System.out.println("finished.");}public static void copyFile(String src,String des){File f1 = new File(src);File f2 = new File(des);InputStream in = null;OutputStream out = null;try {in = new FileInputStream(f1);out = new FileOutputStream(f2);byte[] bs = new byte[105];int len = -1;while((len=in.read(bs))!=-1){out.write(bs,0,len);}} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();} finally{try {in.close();out.close();} catch (IOException ex) {ex.printStackTrace();}}}
}

/*** 转换流：将一个字节流转换为字符流，也可以将一个字符流转换为字节流* OutputStreamWriter：可以将输出的字符流转换为字节流的输出形式，可使用指定的charset将要写入流*                     中的字符编码成字节。* InputStreamReader：将输入的字节流转换为字符流输入形式，使用指定的charset读取字节并将其解码为*                    字符。*/
public class Main {public static void main(String[] args) {//writer();
        reader();System.out.println("finished.");}public static void writer(){ //把字符流转成字节流try {OutputStream out = new FileOutputStream("c:\\fuck\\javaTest1.txt"); String info = "你好吗abc.";Writer w1 = new OutputStreamWriter(out); //通过字节输出流构造一个字符输出流
            w1.write(info);w1.close();out.close();} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();}}public static void reader(){ //把字节流转成字符流try {InputStream in = new FileInputStream("c:\\fuck\\javaTest1.txt"); Reader r1 = new InputStreamReader(in);char[] cs = new char[105];int len = -1;StringBuilder sb = new StringBuilder();while((len=r1.read(cs))!=-1){sb.append(new String(cs,0,len));}r1.close();in.close();System.out.println(sb);} catch (FileNotFoundException ex) {ex.printStackTrace();} catch (IOException ex) {ex.printStackTrace();}}
}