FileUtils

/* * file name:  FileUtil.java * copyright:  Unis Cloud Information Technology Co., Ltd. Copyright 2015,  All rights reserved * description:  <description> * mofidy staff:  zheng * mofidy time:  2015年10月10日 */package com.utils;import java.io.File;import java.io.FileFilter;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.net.URL;import java.nio.file.Files;import java.util.ArrayList;import java.util.Collection;import java.util.Date;import java.util.Iterator;import java.util.List;import org.apache.commons.io.FileUtils;import org.apache.commons.io.FilenameUtils;import org.apache.commons.io.LineIterator;import org.apache.commons.lang.CharSetUtils;/** * General file manipulation utilities. *  * Facilities are provided in the following areas: * <ul> * <li>writing to a file * <li>reading from a file * <li>make a directory including parent directories * <li>copying files and directories * <li>deleting files and directories * <li>converting to and from a URL * <li>listing files and directories by filter and extension * <li>comparing file content * <li>file last changed date * <li>calculating a checksum *  * @author  zheng * @version  [version, 2015年10月10日] * @see  [about class/method] * @since  [product/module version] */public class FileUtil {    public static void main(String[] args) throws IOException {        //get the path of file        File file = FileUtils.getFile("/Users/zheng/zhengTest/lalala.txt");        File file1 = FileUtils.getFile(new File("/Users/zheng/zhengTest"), "lalala.txt");                //get the file,if not exist then create ; if exist then delete        File file2 = new File("/Users/zheng/zhengTest/ttt.txt");        if(!file2.exists()){            file2.createNewFile();        }        if(file.getName().equals("ttt.txt")){            file2.delete();        }        //get the path and URI of file        file2.toPath();  //--/Users/zheng/zhengTest/ttt.txt        file2.toURI();  //--file:/Users/zheng/zhengTest/ttt.txt                //the path to the system/user temporary directory.        String path = FileUtils.getTempDirectoryPath();        File file3 = FileUtils.getTempDirectory();        String path2 = FileUtils.getUserDirectoryPath();        File file4 = FileUtils.getUserDirectory();                //创建FileInputStream实例对象时，指定的文件应当是存在和可读的。        //Opens a FileInputStream for the specified file, providing better error messages than simply calling new FileInputStream(file)        FileInputStream inputStream = FileUtils.openInputStream(new File("/Users/zheng/zhengTest/ttt.txt"));        byte[] bytes = new byte[inputStream.available()];  //新建一个字节数组        //char[] buf = new char[1024]; --字符流Reader类和Writer类使用        int length = inputStream.read(bytes);  //将文件中的内容读取到字节数组中        inputStream.close();        String s = new String(bytes, 0, length);  //再将字节数组中的内容转化成字符串形式输出                //创建FileOutputStream实例对象时，如果指定的文件已经存在，这个文件中的原来内容将被覆盖清除(但不能指定一个已被其他程序打开了的文件).        //Opens a FileOutputStream for the specified file, checking and creating the parent directory if it does not exist.        FileOutputStream outputStream = FileUtils.openOutputStream(new File("/Users/zheng/zhengTest/tt.txt"));        outputStream.write(bytes, 0, length);        outputStream.close();                //Implements the same behaviour as the "touch" utility on Unix.        //It creates a new file with size 0 or, if the file exists already, it is opened and closed without modifying it, but updating the file date and time.        FileUtils.touch(new File("/Users/zheng/zhengTest/tt.txt"));                //把相应的文件集合转换成文件数组convertFileCollectionToFileArray(Collection<File> files)                //根据一个过滤规则获取一个目录下的文件innerListFiles(Collection<File> files, File directory,IOFileFilter filter)        //根据一个IOFileFilter过滤规则获取一个目录下的文件集合listFiles( File directory, IOFileFilterfileFilter, IOFileFilter dirFilter)                //把指定的字符串数组变成后缀名格式字符串数组toSuffixes(String[] extensions)                //Finds files within a given directory (and optionally its subdirectories) which match an array of extensions.        String[] extensions = {"txt","sh"};        Collection<File> files1 = FileUtils.listFiles(new File("/Users/zheng/zhengTest"), extensions, true);        for(File f : files1){            System.out.println(f.getName());        }                //查找一个目录下面符合对应扩展名的文件的集合的迭代器Iterator<File> iterateFiles( File directory, String[]extensions, boolean recursive)        //Allows iteration over the files in a given directory (and optionally its subdirectories) which match an array of extensions.         //This method is based on {@link #listFiles(File, String[], boolean)},which supports Iterable ('foreach' loop).        Iterator<File> files2 = FileUtils.iterateFiles(new File("/Users/zheng/zhengTest"), extensions, true);        while(files2.hasNext()){            System.out.println(files2.next().getName());        }                //Compares the contents of two files to determine if they are equal or not.        boolean flag = FileUtils.contentEquals(new File("/Users/zheng/zhengTest/tt.txt"), new File("/Users/zheng/zhengTest/ttt.txt"));        //这里使用了charsetName，用以获取编码后的字符流        boolean flag1 = FileUtils.contentEqualsIgnoreEOL(new File("/Users/zheng/zhengTest/tt.txt"), new File("/Users/zheng/zhengTest/ttt.txt"), "UTF-8");                //Convert from a URL to a File        File file5 = FileUtils.toFile(new URL("file:///Users/zheng/zhengTest/ttt.txt"));                //Converts each of an array of File to a URL        File[] files3 = new File[1];        files3[0] = new File("/Users/zheng/zhengTest/ttt.txt");        URL[] urls = FileUtils.toURLs(files3);        for(URL url : urls){            System.out.println(url);        }                //Copies a file to a directory preserving the file date.        FileUtils.copyFileToDirectory(new File("/Users/zheng/zhengTest/ttt.txt"), new File("/Users/zheng"));        FileUtils.copyFileToDirectory(new File("/Users/zheng/zhengTest/ttt.txt"), new File("/Users/zheng/test"), true);        //Copies a file to a new location preserving the file date.        FileUtils.copyFile(new File("/Users/zheng/zhengTest/ttt.txt"), new File("/Users/zheng/zhengTest/tttaaa.txt"));        FileUtils.copyFile(new File("/Users/zheng/zhengTest/ttt.txt"), new File("/Users/zheng/zhengTest/tttaaa.txt"), true);                //Copy bytes from a File to an OutputStream        long length1 = FileUtils.copyFile(new File("/Users/zheng/zhengTest/tt.txt"),new FileOutputStream("lalala"));        //Copies bytes from an InputStream source to a file        FileUtils.copyInputStreamToFile(new FileInputStream(new File("/Users/zheng/zhengTest/abc.txt")), new File("/Users/zheng/zhengTest/ttt.txt"));                //Copies a directory to within another directory preserving the file dates.  --copy文件夹到某个文件夹        FileUtils.copyDirectoryToDirectory(new File("/Users/zheng/zhengTest"), new File("/Users/zheng/shanchu"));        //Copies a whole directory to a new location preserving the file dates. --copy文件夹下的内容到某个文件夹        FileUtils.copyDirectory(new File("/Users/zheng/zhengTest"), new File("/Users/zheng/shanchu"));        FileUtils.copyDirectory(new File("/Users/zheng/zhengTest"), new File("/Users/zheng/shanchu"), true);                //Copies bytes from the URL source to a file        FileUtils.copyURLToFile(new URL("file:///Users/zheng/zhengTest/ttt.txt"), new File("/Users/zheng/zhengTest/xsa.txt"));        FileUtils.copyURLToFile(new URL("file:///Users/zheng/zhengTest/ttt.txt"), new File("/Users/zheng/zhengTest/xsa.txt"), 1000, 2000);                //Deletes a directory recursively.         FileUtils.deleteDirectory(new File("/Users/zheng/zhengTest/haha"));        //Schedules a directory recursively for deletion on JVM exit.        FileUtils.deleteDirectoryOnExit(new File("/Users/zheng/zhengTest/haha"));        //Deletes a file, never throwing an exception. If file is a directory, delete it and all sub-directories.        FileUtils.deleteQuietly(new File("/Users/zheng/zhengTest/haha"));                //Deletes a file. If file is a directory, delete it and all sub-directories.        FileUtils.forceDelete(new File("/Users/zheng/zhengTest"));        //Schedules a file to be deleted when JVM exits. If file is directory delete it and all sub-directories.        FileUtils.forceDeleteOnExit(new File("/Users/zheng/zhengTest"));                //Determines whether the {@code parent} directory contains the {@code child} element (a file or directory).        boolean flag2 = FileUtils.directoryContains(new File("/Users/zheng/zhengTest"), new File("/Users/zheng/zhengTest/xsaa.txt"));                //Cleans a directory without deleting it.        FileUtils.cleanDirectory(new File("/Users/zheng/zhengTest/haha"));        //Cleans a directory without deleting it.        FileUtils.cleanDirectoryOnExit(new File("/Users/zheng/zhengTest/haha"));                //Waits for NFS to propagate a file creation, imposing a timeout.        //This method repeatedly tests {@link File#exists()} until it returns true up to the maximum time specified in seconds.        //public static boolean waitFor(File file, int seconds)                //Reads the contents of a file into a String. The file is always closed.        String str = FileUtils.readFileToString(new File("/Users/zheng/zhengTest/ttt.txt"), "UTF-8");        //Reads the contents of a file into a byte array. The file is always closed.        //public static byte[] readFileToByteArray(File file);                //Reads the contents of a file line by line to a List of Strings. The file is always closed.        List<String> list = FileUtils.readLines(new File("/Users/zheng/zhengTest/ttt.txt"),"UTF-8");        for(String str2:list){            System.out.println(str2);        }                //Returns an Iterator for the lines in a <code>File        //This method opens an <code>InputStream</code> for the file.When you have finished with the iterator you should close the stream        //to free internal resources. This can be done by calling the {@link LineIterator#close()} or {@link LineIterator#closeQuietly(LineIterator)} method.        LineIterator lineIterator = FileUtils.lineIterator(new File("/Users/zheng/zhengTest/ttt.txt"), "UTF-8");        try {            while (lineIterator.hasNext()) {                System.out.println(lineIterator.nextLine());            }         }finally{            LineIterator.closeQuietly(lineIterator);        }                //Writes a String to a file creating the file if it does not exist.        //NOTE: As from v1.3, the parent directories of the file will be created if they do not exist.        FileUtils.writeStringToFile(new File("/Users/zheng/zhengTest/ttt.txt"), "qwe123", "UTF-8");                //Writes a String to a file creating the file if it does not exist.        //append if {@code true}, then the String will be added to the end of the file rather than overwriting        FileUtils.writeStringToFile(new File("/Users/zheng/zhengTest/ttt.txt"), "456789", "UTF-8", true);                //Writes the <code>toString()</code> value of each item in a collection to the specified <code>File</code> line by line, optionally appending.        //The specified character encoding and the default line ending will be used.        List<String> list1 = new ArrayList<String>();        list1.add("123");        list1.add("456");        list1.add("789");        FileUtils.writeLines(new File("/Users/zheng/zhengTest/ttt.txt"), "UTF-8", list1, false);                //Makes a directory, including any necessary but nonexistent parent directories.         //If a file already exists with specified name but it is not a directory then an IOException is thrown.        //If the directory cannot be created (or does not already exist) then an IOException is thrown.        public static void forceMkdir(File directory);                //Checks that the given {@code File} exists and is a directory.        private static void checkDirectory(File directory);                //Tests if the specified <code>File</code> is newer than the specified Date.        public static boolean isFileNewer(File file, Date date) ;        //Tests if the specified <code>File</code> is older than the specified Date        public static boolean isFileOlder(File file, Date date);                 //Tests if the specified <code>File</code> is newer than the reference File.        boolean flag6 = FileUtils.isFileNewer(new File("/Users/zheng/zhengTest/tt.txt"), new File("/Users/zheng/zhengTest/ttt.txt"));        //Tests if the specified <code>File</code> is newer than the reference File        public static boolean isFileNewer(File file, File reference);        //Tests if the specified <code>File</code> is older than the reference File        public static boolean isFileOlder(File file, File reference);                 //Tests if the specified <code>File</code> is newer than the specified time reference.        public static boolean isFileNewer(File file, long timeMillis)        //Tests if the specified <code>File</code> is older than the specified time reference.        public static boolean isFileOlder(File file, long timeMillis);                 //Moves a directory.When the destination directory is on another file system, do a "copy and delete".        FileUtils.moveDirectory(new File("/Users/zheng/zhengTest/haha"), new File("/Users/zheng/zhengTest/123/haha"));        //Moves a file to another directory.        //@param createDestDir If {@code true} create the destination directory,otherwise if {@code false} throw an IOException        public static void moveDirectoryToDirectory(File src, File destDir, boolean createDestDir);        //Moves a file to a directory.        public static void moveFileToDirectory(File srcFile, File destDir, boolean createDestDir)         //Moves a file or directory to the destination directory. When the destination is on another file system, do a "copy and delete".        public static void moveToDirectory(File src, File destDir, boolean createDestDir);        //Moves a file. When the destination file is on another file system, do a "copy and delete".        FileUtils.moveFile(new File("/Users/zheng/zhengTest/tt.txt"), new File("/Users/zheng/zhengTest/123/tt.txt"));                 /**         * Returns the size of the specified file or directory. If the provided          * {@link File} is a regular file, then the file's length is returned.         * If the argument is a directory, then the size of the directory is         * calculated recursively. If a directory or subdirectory is security          * restricted, its size will not be included.         */        long size = FileUtils.sizeOf(new File("/Users/zheng/zhengTest/ttt.txt"));        //Counts the size of a directory recursively (sum of the length of all files).        long size1 = FileUtils.sizeOf(new File("/Users/zheng/zhengTest"));                /**         * Determines whether the specified file is a Symbolic Link rather than an actual file.         * Will not return true if there is a Symbolic Link anywhere in the path,         * only if the specific file is.         * <b>Note:</b> the current implementation always returns {@code false} if the system         * is detected as Windows using {@link FilenameUtils#isSystemWindows()}         */        public static boolean isSymlink(File file);    }}