Java I/O (1)

         File f =  new File( "d:/LOLFolder/LOL.exe" );          System.out.println( "当前文件是：" +f);          //文件是否存在          System.out.println( "判断是否存在：" +f.exists());                   //是否是文件夹          System.out.println( "判断是否是文件夹：" +f.isDirectory());                    //是否是文件（非文件夹）          System.out.println( "判断是否是文件：" +f.isFile());                    //文件长度          System.out.println( "获取文件的长度：" +f.length());                    //文件最后修改时间          long time = f.lastModified();          Date d =  new Date(time);          System.out.println( "获取文件的最后修改时间：" +d);          //设置文件修改时间为1970.1.1 08:00:00          f.setLastModified( 0 );                    //文件重命名          File f2 = new File( "d:/LOLFolder/DOTA.exe" );          f.renameTo(f2);          System.out.println( "把LOL.exe改名成了DOTA.exe" );    // 以字符串数组的形式，返回当前文件夹下的所有文件（不包含子文件及子文件夹）          f.list();            // 以文件数组的形式，返回当前文件夹下的所有文件（不包含子文件及子文件夹）          File[]fs= f.listFiles();            // 以字符串形式返回获取所在文件夹          f.getParent();            // 以文件形式返回获取所在文件夹          f.getParentFile();          // 创建文件夹，如果父文件夹skin不存在，创建就无效          f.mkdir();            // 创建文件夹，如果父文件夹skin不存在，就会创建父文件夹          f.mkdirs();            // 创建一个空文件,如果父文件夹skin不存在，就会抛出异常          f.createNewFile();          // 所以创建一个空文件之前，通常都会创建父目录          f.getParentFile().mkdirs();            // 列出所有的盘符c: d: e: 等等          f.listRoots();            // 刪除文件          f.delete();            // JVM结束的时候，刪除文件，常用于临时文件的删除          f.deleteOnExit();When there is data interaction between different media, Java uses a stream to implement it.
The data source can be a file, a database, a network, or even other programs


such as reading the file data into the program, from the point of view of the program, is called the input stream
Input stream: InputStream
Output stream: OutputStream recommendations for the closure of a flow in the finally or try () this is a technique called try-with-resources, which starts with support from JDK7. There are several coding methods that are often contacted:
iso-8859-1 ASCII digits and western European alphabet
GBK GB2312 BIG5 Chinese
UNICODE (Uniform Code, Universal Code) cache character input stream BufferedReader can read one row of data at a timeprintwriter cache character output stream, can write one row of data at a timeSometimes it is necessary to write the data to the hard disk immediately, instead of waiting until the cache is full. This is where flush is needed .

Java I/O (1)