java 文件流的帮助类

package Demo8;

import java.io.*;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;


public class FileUtil {
    String newline = "\r\n";//windows

    /**
     * 写入文件,末尾自动添加\r\n
     * utf-8  追加
     *
     * @param path
     * @param str
     */
    public static void writeLog(String path, String str) {
        try {
//            File file = new File(path);
//            if (!file.exists())
//                file.createNewFile();
//            FileOutputStream out = new FileOutputStream(file); //true表示追加
//            StringBuffer sb = new StringBuffer();
//
//
//            sb.append(str + "\r\n");
//            out.write(sb.toString().getBytes("utf-8"));//
//            out.close();

            File file = new File(path);
            RandomAccessFile raf = new RandomAccessFile(file, "rw");
            //将写文件指针移到文件尾。
            raf.seek(raf.length());
            raf.writeBytes(str+"\r\n");
            raf.close();
        } catch (IOException ex) {
            System.out.println(ex.getStackTrace());
        }
    }

    /**
     * 写入文件,末尾自动添加\r\n
     *
     * @param path
     * @param str
     */
    public static void writeLog(String path, String str, boolean is_append, String encode) {
        try {
            File file = new File(path);
            if (!file.exists())
                file.createNewFile();
            FileOutputStream out = new FileOutputStream(file, is_append); //true表示追加
            StringBuffer sb = new StringBuffer();
            sb.append(str + "\r\n");
            out.write(sb.toString().getBytes(encode));//
            out.close();
        } catch (IOException ex) {
            System.out.println(ex.getStackTrace());
        }
    }

    /**
     * 整个文件以string放回，添加\r\n换行
     *
     * @param path
     * @return
     */
    public static String readLogByString(String path) {
        StringBuffer sb = new StringBuffer();
        String tempstr = null;
        try {
            File file = new File(path);
            if (!file.exists())
                throw new FileNotFoundException();
            FileInputStream fis = new FileInputStream(file);
            BufferedReader br = new BufferedReader(new InputStreamReader(fis, "utf-8"));
            while ((tempstr = br.readLine()) != null) {
                sb.append(tempstr + "\r\n");
            }
        } catch (IOException ex) {
            System.out.println(ex.getStackTrace());
        }
        return sb.toString();
    }

    /**
     * 加入编码
     * 整个文件以string放回，添加\r\n换行
     *
     * @param path
     * @return
     */
    public static String readLogByStringAndEncode(String path, String encode) {
        StringBuffer sb = new StringBuffer();
        String tempstr = null;
        try {
            File file = new File(path);
            if (!file.exists())
                throw new FileNotFoundException();
            FileInputStream fis = new FileInputStream(file);
            BufferedReader br = new BufferedReader(new InputStreamReader(fis, encode));
            while ((tempstr = br.readLine()) != null) {
                sb.append(tempstr + "\r\n");
            }
        } catch (IOException ex) {
            System.out.println(ex.getStackTrace());
        }
        return sb.toString();
    }

    /**
     * 按行读取文件，以list<String>的形式返回
     *
     * @param path
     * @return
     */
    public static List<String> readLogByList(String path) {
        List<String> lines = new ArrayList<String>();
        String tempstr = null;
        try {
            File file = new File(path);
            if (!file.exists()) {
                throw new FileNotFoundException();
            }
            FileInputStream fis = new FileInputStream(file);
            BufferedReader br = new BufferedReader(new InputStreamReader(fis, "utf-8"));
            while ((tempstr = br.readLine()) != null) {
                lines.add(tempstr.toString());
            }
        } catch (IOException ex) {
            System.out.println(ex.getStackTrace());
        }
        return lines;
    }


    /**
     * 创建目录
     *
     * @param dir_path
     */
    public static void mkDir(String dir_path) {
        File myFolderPath = new File(dir_path);
        try {
            if (!myFolderPath.exists()) {
                myFolderPath.mkdir();
            }
        } catch (Exception e) {

            e.printStackTrace();
        }
    }

    /**
     * 创建文件
     *
     * @param file_path
     */
    public static void createNewFile(String file_path) {
        File myFilePath = new File(file_path);
        try {
            if (!myFilePath.exists()) {
                myFilePath.createNewFile();
            }
        } catch (Exception e) {

            e.printStackTrace();
        }
    }


    /**
     * 递归删除文件或者目录
     *
     * @param file_path
     */
    public static void deleteEveryThing(String file_path) {
        try {
            File file = new File(file_path);
            if (!file.exists()) {
                return;
            }
            if (file.isFile()) {
                file.delete();
            } else {
                File[] files = file.listFiles();
                for (int i = 0; i < files.length; i++) {
                    String root = files[i].getAbsolutePath();//得到子文件或文件夹的绝对路径
                    deleteEveryThing(root);
                }
                file.delete();
            }
        } catch (Exception e) {
        }
    }


    /*
     * 得到一个文件夹下所有文件
     */
    public static List<String> getAllFileNameInFold(String fold_path) {
        List<String> file_paths = new ArrayList<String>();

        LinkedList<String> folderList = new LinkedList<String>();
        folderList.add(fold_path);
        while (folderList.size() > 0) {
            File file = new File(folderList.peekLast());
            folderList.removeLast();
            File[] files = file.listFiles();
            ArrayList<File> fileList = new ArrayList<File>();
            for (int i = 0; i < files.length; i++) {
                if (files[i].isDirectory()) {
                    folderList.add(files[i].getPath());
                } else {
                    fileList.add(files[i]);
                }
            }
            for (File f : fileList) {
                file_paths.add(f.getAbsoluteFile().getPath());
            }
        }
        return file_paths;
    }
}