Java中创建操作文件和文件夹的工具类

Java中创建操作文件和文件夹的工具类

FileUtils.java

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.nio.channels.FileChannel;

import org.junit.Test;

/**
 * 
 * @version 创建时间：2010-6-8 下午02:58:29
 * @Description
 */

public class FileUtils {
    /**
     * 获取文件编码格式
     * @param fileName
     * @return
     * @throws Exception
     */
    public static String getFileEncoding(String fileName) throws Exception {
        BufferedInputStream bin = new BufferedInputStream(new FileInputStream(fileName));
        int p = (bin.read() << 8) + bin.read();
        String code = null;
        switch (p) {
        case 0xefbb:
            code = "UTF-8";
            break;
        case 0xfffe:
            code = "Unicode";
            break;
        case 0xfeff:
            code = "UTF-16BE";
            break;
        default:
            code = "GBK";
        }

        return code;
    }
    
    /**
     * 拷贝文件到指定的路径 (使用了自定义的CopyFileUtil工具类)
     * @param fileURL
     * @param targetFile
     */
    public void copy(String fileURL ,String targetFile){
        URLConnection urlconn = null ;
        try {
            URL url = new URL(fileURL);
            urlconn = url.openConnection();
            InputStream in = urlconn.getInputStream();

            File newfile = new File(targetFile);        
            FileOutputStream fos = new FileOutputStream(newfile);
            CopyFileUtil.copy(in, fos);//使用了自定义的FileUtil工具类
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } 
    }
    
    
    /**
     * 复制文件
     * @param sourceFile
     * @param targetFile
     * @throws IOException
     */
    public static void copyFile(File sourceFile, File targetFile)
            throws IOException {
        // 新建文件输入流并对它进行缓冲
        FileInputStream input = new FileInputStream(sourceFile);
        BufferedInputStream inBuff = new BufferedInputStream(input);
        // 新建文件输出流并对它进行缓冲
        FileOutputStream output = new FileOutputStream(targetFile);
        BufferedOutputStream outBuff = new BufferedOutputStream(output);
        // 缓冲数组
        byte[] b = new byte[1024 * 5];
        int len;
        while ((len = inBuff.read(b)) != -1) {
            outBuff.write(b, 0, len);
        }
        // 刷新此缓冲的输出流
        outBuff.flush();
        // 关闭流
        inBuff.close();
        outBuff.close();
        output.close();
        input.close();
    }

    /**
     * 复制文件夹
     * @param sourceDir
     * @param targetDir
     * @throws IOException
     */
    public static void copyDirectiory(String sourceDir, String targetDir)
            throws IOException {
        // 新建目标目录
        (new File(targetDir)).mkdirs();
        // 获取源文件夹当前下的文件或目录
        File[] file = (new File(sourceDir)).listFiles();
        for (int i = 0; i < file.length; i++) {
            if (file[i].isFile()) {
                // 源文件
                File sourceFile = file[i];
                // 目标文件
                File targetFile = new File(new File(targetDir)
                        .getAbsolutePath()
                        + File.separator + file[i].getName());
                if (sourceFile.getName().indexOf(".vax") < 0)
                    copyFile(sourceFile, targetFile);
            }
            if (file[i].isDirectory()) {
                // 准备复制的源文件夹
                String dir1 = sourceDir + "/" + file[i].getName();
                // 准备复制的目标文件夹
                String dir2 = targetDir + "/" + file[i].getName();
                copyDirectiory(dir1, dir2);
            }
        }
    }
    
    /**
     * 得到文件的扩展名
     * @param f
     * @return
     */
    public static String getFileExtension(File f) {
        if (f != null) {
            String filename = f.getName();
            int i = filename.lastIndexOf('.');
            if (i > 0 && i < filename.length() - 1) {
                return filename.substring(i + 1).toLowerCase();
            }
        }
        return null;
    }
    /**
     * 得到文件名(排除文件扩展名)
     * @param f
     * @return
     */
    public static String getFileNameWithoutExt(File f) {
        if (f != null) {
            String filename = f.getName();
            int i = filename.lastIndexOf('.');
            if (i > 0 && i < filename.length() - 1) {
                return filename.substring(0, i);
            }
        }
        return null;
    }
    
    /**
     * 改变文件的扩展名
     * @param fileNM
     * @param ext
     * @return
     */
    public static String changeFileExt(String fileNM, String ext) {
        int i = fileNM.lastIndexOf('.');
        if (i >= 0)
            return (fileNM.substring(0, i) + ext);
        else
            return fileNM;
    }
    
    /**
     * 得到文件的全路径
     * @param filePath
     * @return
     */
    public static String getFileNameWithFullPath(String filePath) {
        int i = filePath.lastIndexOf('/');
        int j = filePath.lastIndexOf("\");
        int k;
        if (i >= j) {
            k = i;
        } else {
            k = j;
        }
        int n = filePath.lastIndexOf('.');
        if (n > 0) {
            return filePath.substring(k + 1, n);
        } else {
            return filePath.substring(k + 1);
        }
    }



    /**
     * 判断目录是否存在
     * @param strDir
     * @return
     */
    public static boolean existsDirectory(String strDir) {
        File file = new File(strDir);
        return file.exists() && file.isDirectory();
    }
    
    /**
     * 判断文件是否存在
     * @param strDir
     * @return
     */
    public static boolean existsFile(String strDir) {
        File file = new File(strDir);
        return file.exists();
    }
    
    /**
     * 强制创建目录
     * @param strDir
     * @return
     */
    public static boolean forceDirectory(String strDir) {
        File file = new File(strDir);
        file.mkdirs();
        return existsDirectory(strDir);
    }
    
    /**
     * 得到文件的大小
     * @param fileName
     * @return
     */
    public static int getFileSize(String fileName){
        
        File file = new File(fileName);
        FileInputStream fis = null;
        int size = 0 ;
        try {
            fis = new FileInputStream(file);
            size = fis.available();
        }catch (Exception e) {
            e.printStackTrace();
        }
        return size ;
    }

}

CpoyFileUtil.java(主要都是文件复制相关的方法)

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.StringWriter;
import java.io.Writer;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.text.CollationKey;
import java.text.Collator;
import java.text.RuleBasedCollator;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;

import org.apache.log4j.Logger;

/**
 * Simple utility methods for file and stream copying.
 * All copy methods use a block size of 4096 bytes,
 * and close all affected streams when done.
 *
 * <p>Mainly for use within the framework,
 * but also useful for application code.
 *
 * @author John Summer
 */
public abstract class CopyFileUtil {

    private static final Logger logger = Logger.getLogger(FileUtil.class);

    public static final int BUFFER_SIZE = 4096;

    /**
     * judge whether it's exist
     * @param strFilePath String
     * @return boolean
     */
    public static boolean isExist(String filepath) {
        File file = new File(filepath);
        return file.exists();
    }
    
    public static void copy(String fileURL ,String targetFile){
        URLConnection urlconn = null ;
        try {
            URL url = new URL(fileURL);
            urlconn = url.openConnection();
            InputStream in = urlconn.getInputStream();

            File newfile = new File(targetFile);        
            FileOutputStream fos = new FileOutputStream(newfile);
            FileUtil.copy(in, fos);                
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } 
    }
    
    /**
     * Copy the contents of the given input File to the given output File.
     * @param in the file to copy from
     * @param out the file to copy to
     * @return the number of bytes copied
     * @throws IOException in case of I/O errors
     */
    public static int copy(File in, File out) throws IOException {
        Assert.notNull(in, "No input File specified");
        Assert.notNull(out, "No output File specified");
        return copy(new BufferedInputStream(new FileInputStream(in)),
            new BufferedOutputStream(new FileOutputStream(out)));
    }

    /**
     * Copy the contents of the given byte array to the given output File.
     * @param in the byte array to copy from
     * @param out the file to copy to
     * @throws IOException in case of I/O errors
     */
    public static void copy(byte[] in, File out) throws IOException {
        Assert.notNull(in, "No input byte array specified");
        Assert.notNull(out, "No output File specified");
        ByteArrayInputStream inStream = new ByteArrayInputStream(in);
        OutputStream outStream = new BufferedOutputStream(new FileOutputStream(out));
        copy(inStream, outStream);
    }

    /**
     * Copy the contents of the given input File into a new byte array.
     * @param in the file to copy from
     * @return the new byte array that has been copied to
     * @throws IOException in case of I/O errors
     */
    public static byte[] copyToByteArray(File in) throws IOException {
        Assert.notNull(in, "No input File specified");
        return copyToByteArray(new BufferedInputStream(new FileInputStream(in)));
    }

    /**
     * Copy the contents of the given InputStream to the given OutputStream.
     * Closes both streams when done.
     * @param in the stream to copy from
     * @param out the stream to copy to
     * @return the number of bytes copied
     * @throws IOException in case of I/O errors
     */
    public static int copy(InputStream in, OutputStream out) throws IOException {
        Assert.notNull(in, "No InputStream specified");
        Assert.notNull(out, "No OutputStream specified");
        try {
            int byteCount = 0;
            byte[] buffer = new byte[BUFFER_SIZE];
            int bytesRead = -1;
            while ((bytesRead = in.read(buffer)) != -1) {
                out.write(buffer, 0, bytesRead);
                byteCount += bytesRead;
            }
            out.flush();
            return byteCount;
        }
        finally {
            try {
                in.close();
            }
            catch (IOException ex) {
                logger.warn("Could not close InputStream", ex);
            }
            try {
                out.close();
            }
            catch (IOException ex) {
                logger.warn("Could not close OutputStream", ex);
            }
        }
    }

    /**
     * Copy the contents of the given byte array to the given OutputStream.
     * Closes the stream when done.
     * @param in the byte array to copy from
     * @param out the OutputStream to copy to
     * @throws IOException in case of I/O errors
     */
    public static void copy(byte[] in, OutputStream out) throws IOException {
        Assert.notNull(in, "No input byte array specified");
        Assert.notNull(out, "No OutputStream specified");
        try {
            out.write(in);
        }
        finally {
            try {
                out.close();
            }
            catch (IOException ex) {
                logger.warn("Could not close OutputStream", ex);
            }
        }
    }

    /**
     * Copy the contents of the given InputStream into a new byte array.
     * Closes the stream when done.
     * @param in the stream to copy from
     * @return the new byte array that has been copied to
     * @throws IOException in case of I/O errors
     */
    public static byte[] copyToByteArray(InputStream in) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream(BUFFER_SIZE);
        copy(in, out);
        return out.toByteArray();
    }

    /**
     * Copy the contents of the given Reader to the given Writer.
     * Closes both when done.
     * @param in the Reader to copy from
     * @param out the Writer to copy to
     * @return the number of characters copied
     * @throws IOException in case of I/O errors
     */
    public static int copy(Reader in, Writer out) throws IOException {
        Assert.notNull(in, "No Reader specified");
        Assert.notNull(out, "No Writer specified");
        try {
            int byteCount = 0;
            char[] buffer = new char[BUFFER_SIZE];
            int bytesRead = -1;
            while ((bytesRead = in.read(buffer)) != -1) {
                out.write(buffer, 0, bytesRead);
                byteCount += bytesRead;
            }
            out.flush();
            return byteCount;
        }
        finally {
            try {
                in.close();
            }
            catch (IOException ex) {
                logger.warn("Could not close Reader", ex);
            }
            try {
                out.close();
            }
            catch (IOException ex) {
                logger.warn("Could not close Writer", ex);
            }
        }
    }

    /**
     * Copy the contents of the given String to the given output Writer.
     * Closes the write when done.
     * @param in the String to copy from
     * @param out the Writer to copy to
     * @throws IOException in case of I/O errors
     */
    public static void copy(String in, Writer out) throws IOException {
        Assert.notNull(in, "No input String specified");
        Assert.notNull(out, "No Writer specified");
        try {
            out.write(in);
        }
        finally {
            try {
                out.close();
            }
            catch (IOException ex) {
                logger.warn("Could not close Writer", ex);
            }
        }
    }

    /**
     * Copy the contents of the given Reader into a String.
     * Closes the reader when done.
     * @param in the reader to copy from
     * @return the String that has been copied to
     * @throws IOException in case of I/O errors
     */
    public static String copyToString(Reader in) throws IOException {
        StringWriter out = new StringWriter();
        copy(in, out);
        return out.toString();
    }

}